Jacking, which is one of operation modes for jack up, is a specific way to raise up a hull of a jack up rig so this article will describe about the basic of jacking and preloading operation.

Jacking Operation

Mat jack up units (figure 1) jack the mat to the seabed, in accordance with the ballasting procedure. When the mat is fully lowered, the hull is then jacked out of the water. After this is complete, the unit will then proceed to preload operations. It is vital that all independent leg units also perform preload operations before being jacked to the design air gap. The majority of independent leg units lack the capacity needed to fully elevate the Jack Up unit while the preload weight is still aboard. In these cases, the next step will be to jack the hull out of the water until a very small air gap is achieved- this should be at the very most 5 feet. Once this has been reached, then preload operations can continue.

Figure 1 – Mat Footing Jack Up Rig

However, some more modern independent leg units (figure 2) possess elevating systems that are indeed capable of lifting the full weight of the hull at maximum preload weight. With these units, the preload will be loaded onto the unit before the hull is raised out of the water. Once the entire preload has been loaded, the Jack Up unit is slowly jacked out of the water to the same small preload air gap as other units, under 5 feet.

Figure 2 – A Jack Up Rig with independent leg units (http://www.saff-rosemond.com, 2018)

Preloading Operation

Every Jack Up unit needs to load the supporting soil to the maximum amount of force expected to be exerted under the most extreme conditions- usually, this will be when the unit is in its Storm Survival mode. By carrying out this preload, the risk of a foundation shift or failure during a storm is significantly reduced. However, it is possible that soil failure or a leg shift could occur during these preload operations. To reduce the risk of this, which could have disastrous consequences, the hull needs to be kept as close to the waterline as possible while still avoiding wave impact.

In the event of soil failure or a leg shift, the affected leg loses some of its load-carrying capacity, and rapidly starts to move downwards, causing the hull to descend into the water (Figure 3 – Maersk Victory Punch-Through). Furthermore, some of the load that the affected leg was carrying will be transferred onto the other legs, which could overload them as well. The failed leg will continue to penetrate into the soil until the soil gives enough support, or until the hull is sufficiently under the water to provide enough hull buoyancy to halt the penetrations. When the hull is off-level, the legs will all experience increased traverse load and bending moment transferred to the hull, in the most part from the guide. As guide loads increase, some braces will start to experience large compressive loads. Special procedures need to be followed to minimize any structural damage that can occur under these conditions.

Figure 3 – Maersk Victory Punch-Through

While normal preload operations are taking place, it is essential that the weight of the hull, deck load, and preload are all kept as close as possible to the geometric center of the legs. This is so that each leg experiences equal loading. However, it may be the case that single-leg preloading is desired, in order to increase the maximum footing reaction of that particular leg. To do this, the preload tanks need to be selectively filled or emptied, depending on their relative position to the leg currently being preloaded.

The preload takes the form of seawater pumped into tanks inside the hull. Once it has been pumped on board, it will then be help for a certain amount of time. Preloading is only complete once there is no settling of the legs into the soil during the holding period, while also achieving the target footing reaction. How much preload is required will depend on the required environmental reaction, as well as the type of Jack Up unit being used.  Usually, mat units do not require much preload.

Four-legged independent Jack Ups (Figure 4) also require little to no preload water, because they preload two diagonally opposite legs at the same time using just the weight of the hull itself. The unit is jacked to its preload air gap, before two legs are lifted slightly off the seabed. The unit therefore settles on the remaining two legs. The hull is then jacked back up to the preload air gap, and the process is repeated until all four legs are preloaded to the target footing reaction, and no extra penetration occurs.

Figure 4 – Four-Legged Jack Up (http://www.swiftdrilling.com, 2018)

Three-legged independent units (Figure 5), on the other hand, require the most preload water. If they are incapable of jacking with preload, then the water will be pumped aboard once the unit has been jacked to its preload air gap. If a significant amount of settling is experienced, then the full preload will need to be dumped before the hull if jacked upwards again. The process must then be repeated until there is no more settling.

Figure 5 – Three-Legged Jack Up

In the case of units that are able to jack with full preload, the preload will be pumped into the hull while it is still sitting in the water. The hull will then be gradually jacked up, occasionally stopping briefly at predetermined draft points. This process goes on until the hull has reached the preload air hap, and has held the preload for the required holding period. When the preload has been held for the predetermined amount of time, all of the preload water is ejected, and the Jack Up unit can be elevated to its operating air gap.

Jacking to Operation Air Gap

After preload operations have been completed, the unit can be jacked up to its operational air gap (Figure 6). When this is carried out, it is vital that the level of the hull and elevating system load and characteristics are carefully observed, as well as the Rack Phase Differential (RPD) in the case of trussed-leg units. Care must be taken to keep these figures within design limits. When the unit has reached its operation air gap, the jacking system will be stopped and the brakes set, along with leg locking systems if these are present. Once this process is complete, the unit is ready for operations.

Figure 6 – West Elara jack up rig jacks up to the required operation air gap over the production platform (marinetraffic.com, 2015), Photo Taken by Jan Henry Hnusten

While normal operations are taking place, there is no particular difference between the various types of Jack Up unit. Neither are there any special precautionary measures which need to be taken, other than observing the design limits with regards to operation and equipment. However, in the case of units with large cantilever reach and loads, it is important to ensure that the maximum footing reaction remains below a predefined percentage of the reaction achieved during preload.

 Jacking to Storm Survival Air Gap

During operations, it is important that the weather is constantly being monitored. If any storms which exceed the intended operating condition environment are predicted, then operations must be halted, and the Jack Up unit switched to its Storm Survival mode. In this mode, all equipment and stores are fully secured, and extra care is taken to ensure all weather and watertight enclosures are closed. Should cyclonic storms be predicted, then the extra precaution of evacuating personnel from the unit is taken.

References

Members.home.nl. (2010). Maersk Victory Punch-Through – Oil Rig Disasters – Offshore Drilling Accidents. [online] Available at: http://members.home.nl/the_sims/rig/m-victory.htm [Accessed 5 Oct. 2018].

Oilfieldpix.com. (2018). Offshore Jack Up Drilling Rig Over The Production Platform – Oilfield Royalty Free Stock Images and Illustrations. [online] Available at: http://oilfieldpix.com/photo/578/Offshore-Jack-Up-Drilling-Rig-Over-The-Production-Platform.html [Accessed 18 Aug. 2018].

Swift Drilling Ltd. (2018). Completion, Well Testing | Swift Drilling. [online] Swiftdrilling.com. Available at: http://www.swiftdrilling.com/rig_specs/completion_well_testing [Accessed 18 Aug. 2018].

Eurasiadrilling.com. (2018). Jack-up rigs. [online] Available at: http://www.eurasiadrilling.com/operations/offshore/jack-up-rigs/ [Accessed 18 Aug. 2018].

Enscoplc.com. (2018). Ensco plc – Global Operations – Rig Fleet. [online] Available at: https://www.enscoplc.com/global-operations/rig-fleet/default.aspx [Accessed 18 Aug. 2018].

JACK UP – ROSEMOND-SA20 JACK-UP DRILLING RIG DESIGN. (2018). Rosemond-emi. [online] Available at: http://www.saff-rosemond.com/Rosemond-JackUp-Project.html [Accessed 12 Aug. 2018].

Marinetraffic.com. (2015). Picture of WEST ELARA | AIS Marine Traffic. [online] Available at: https://www.marinetraffic.com/en/photos/picture/ships_id/2137538/259783000 [Accessed 5 Oct. 2018].

Mitchell, R.F., Miska, S.Z. and Aadnoy, B.S. (2012) Fundamentals of drilling engineering. Richardson, TX: Society of Petroleum Engineers.

Bork, K. (1995). The rotary rig and its components. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

Davis, L. (1995). Rotary, kelly, swivel, tongs, and top drive. 1st ed. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

The post Basic Knowledge of Jacking Operation for Jack up Rigs appeared first on Drilling Formulas and Drilling Calculations.

When it comes to safety for Jack Ups, there is a rigorous process in place including International Bodies (International Codes), Class Societies (Class Rules), National Legislation (Shelf States), and National Maritime Legislation (Flag States). Although they don’t require a flag, having one enables them to move freely across international waters. When this is planned, the Maritime Authority regulations must be adhered to according to the Flag State (the country whose flag they are flying).

Normally, each drilling unit will be registered with a Flag State Governmental Administration. Essentially, the role of this administration is to set the requirements for each registering unit and these requirements generally follow the lead of the International Maritime Organization (IMO) since these are internally-agreed suggestions. More recently, the responsibility of verifying compliance has been awarded to classification societies and they also issue Marpol certificates, Loadline, and Tonnage.

Moving away from the flag, there are some governments who also request all drilling units to adhere to their own safety regulations when working in their waters. For example, the United Kingdom has a Health and Safety Offshore Division which ensures the safety of all drilling equipment in UK waters.

In terms of classification societies, these are largely independent and have no relation to any other party and this is important because their sole priority is the quality of the Jack Ups. In addition to authorities, these societies could be the owners, insurance underwriters, charterers, sub-contractors, building yards, and finance institutions.

Figure 1 – Jack up Rigs in a Shipyard (gcaptain.com, 2013)

Classification Societies

With regulations and safety laws now introduced, there needs to be someone checking that every company is meeting the demands and this is the role of classification societies. During both design and construction, they will pay particular attention to quality and safety not only for the unit but the environment and personnel too. With each society, you will find different requirements whether it is Lloyds Register, American Bureau of Shipping (ABS), or Det Norske Veritas. This being said, many regulations have been set at a minimum by the International Association of Classification Societies to ensure a minimum quality.

Just like with ships, the rules of classification societies must be met by Jack Up drilling units. When a certificate is awarded, it shows that the unit is compliant with the regulations as well as meeting the minimum industry standard for both mechanical and structural fitness. After the first test, there are normally regular checks thereafter to ensure the unit remains compliant moving forward.

So what do classification societies look for? In truth, there are a number of categories included in every check including structural strength, legs, welding, materials, spud cans, superstructures, and that the Jack Up hull won’t succumb to corrosion. Furthermore, the unit needs to be able to survive in different environments including elevated operations, preloading and jacking, storm survival, etc. In each test, similar grounds will be used to test design such as water depth, hull weight, and environmental conditions depending on what is presented in the manual of the rig. Despite the many inclusions, safety and capacity of the foundation is omitted from these tests. During the approval testing, the owner will also take responsibility for the operation of the Jack Up unit.

Figure 2 – Maersk Jack Up Rig Operating in Hash Environment (csmeshj.ae, 2018)

Naturally, Jack Up units should be mobile since they need to be able to work all over the world. Therefore, there isn’t one specific geographical location used in the rules and the units won’t be judged by one environment or set of conditions. After the unit has been manufactured, the designer and owner will note for which conditions the unit has been designed; this is known as the design criteria and theoretical operating envelope. To be successful, the designer and owner must ensure they meet the regulations of this particular envelope.

As you may know, Jack Up units will generally have both an afloat mode as well as a jacked up mode and this will be tested and analyzed during the process. When in the afloat mode, the leg structures will be checked for roll characteristics as well as gravity bending moment; once again, there will be a focus on storm conditions. For all new Jack Ups, fatigue analysis is also required alongside global structural analysis. Interestingly, many of the regulations were originally derived from the same rules for ships; over time, this has been optimized and adjusted wherever necessary. In addition to this, the common practices were also adjusted such as drilling operations, electrical equipment, fire safety systems, and high-pressure piping systems.

In afloat conditions, Jack Ups have a stability criteria that include the lowering of leg structures. In total, there are two main specified criteria; damage stability and intact stability. Whenever a Jack Up unit has met the minimum standards laid out, this doesn’t necessarily mean that they can operate in every area. Often, the owner will have to take into account the water depth of the water in which they plan to operate in addition to climatic, geotechnical, environmental, and seismic conditions. As a result, there is now a standard called the Society of Naval Architects and Marine Engineers (SNAME) T&R Bulletin 5-5a Guideline for Site Specific Assessment of Mobile Drilling Units; this is now widely used as a guide before performing the appropriate assessment.

Site Specific Assessment

As mentioned previously, Shelf State Legislation is important because each country will lay out their regulations for all those planning to operate Jack Up machinery. Nowadays, most countries are well-regulated and the legislations are vast but there are still some countries who haven’t quite reached this level. In these countries, the oil companies themselves, along with the owners, are responsible for defining their own documentation. As well as referring to their own regulations, they can also follow international guidelines such as those in ‘Recommended Practice’ within the Specific Assessment of Mobile Jack Up Units and this is issued on behalf of the Society of Naval Architects and Marine Engineers (SNAME).

Just as the name suggests, this evaluation will look at just how capable a Jack Up is within a particular location. Normally, the owner of the rig will be provided with the environmental conditions within this region and they then need to prove that their equipment is capable of handling said conditions. In today’s world, most of the large oil companies will have their own criteria alongside the SNAME RP. Ultimately, the SNAME RP is in place so that all Jack Up operations are documented in their global structure strength and foundation capacities. If the soil conditions, rig loads, and actual environment condition fall well within the range of acceptance, the relevant authorities might decide to just consider foundation capacities.

References

Imo.org. (2018). International Maritime Organization. [online] Available at: http://www.imo.org/en/Pages/Default.aspx [Accessed 9 Oct. 2018].

Ww2.eagle.org. (2018). American Bureau of Shipping (ABS) Eagle.org. [online] Available at: https://ww2.eagle.org/en.html [Accessed 9 Oct. 2018].

Almeida, R. (2013). Keppel FELS Makes it 66 With Latest Jack-Up Rig Order – gCaptain. [online] gCaptain. Available at: https://gcaptain.com/keppel-fels-latest-jack-up-order/ [Accessed 9 Oct. 2018].

DNV GL. (2018). DNVGL.com – Safer Smarter Greener – DNV GL. [online] Available at: https://www.dnvgl.com/ [Accessed 9 Oct. 2018].

Lloyd’s Register. (2018). Lloyd’s Register offer smart solutions shaped with human intelligence.. [online] Available at: https://www.lr.org/en/ [Accessed 9 Oct. 2018].

Csmeshj.ae. (2018). CSME | About. [online] Available at: http://csmeshj.ae/about.html [Accessed 9 Oct. 2018].

Society of Naval Architects and Marine Engineers. (2018). Home – SNAME. [online] Available at: https://www.sname.org/home [Accessed 9 Oct. 2018].

Mitchell, R.F., Miska, S.Z. and Aadnoy, B.S. (2012) Fundamentals of drilling engineering. Richardson, TX: Society of Petroleum Engineers.

Bork, K. (1995). The rotary rig and its components. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

Davis, L. (1995). Rotary, kelly, swivel, tongs, and top drive. 1st ed. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

The post Site Specific Assessment and Class Approval for Jack up Rigs appeared first on Drilling Formulas and Drilling Calculations.

This is one of the best drilling 101 videos showing you drilling process from the beginning phase to plug and abandonment phase.  Not only do you learn about drilling, this video briefly shows the overall field development phase. This video tends to focus on unconventional well. For educational purposes, our team provides full video transcript to help anybody learn the content clearly and effectively.

Please see the video below.

 

Full Video Transcript

Drilling a well is a complex process involving ten to thirty different service companies, each one adhering to stringent around the clock scheduling, safety and environmental practices. Understanding how a well is drilled goes a long way toward understanding why producing oil and gas takes so much time and money.

The first step in drilling a well is the planning phase. Members of the oil companies, executive staff and senior exploration team meet to review information associated with a prospect and to get an understanding of the scope of work involved. Research and initial analysis is performed taking into account lease options, potential reserves, risk factors, environmental concerns and costs.

During planning, the goals for the project are set out including if and where to drill and the potential for field development. Geologists, geophysicists and reservoir engineers begin by reviewing both public and proprietary prospect data. Mapping well logs and any existing seismic is evaluated to provide information on the potential of a prospect. Well logs are studied and interpreted to determine the presence of oil or gas in surrounding wells. Mapping shows formation structure, thickness, nearby fields and well activity. Seismic similar to an x-ray but using acoustic energy is used to image or see the targeted area underground and can also verify information seen on other prospect data to determine whether a trapping mechanism for the hydrocarbons exists within the formation.

Once a prospect area has been selected the right to drill must be secured by leasing the mineral rights of the desired property from a landowner or mineral owner. In some cases a landowner may no longer own the mineral rights. An experienced land man is needed to research deed history and negotiate leases. Once titles are researched, blocks of land are put together to create the lease area. An application for a permit, description of the proposed drilling program, a copy of the plat, the permit fee, an environmental assessment, water allocation, air emissions and land use and disturbance must be submitted. Often companies require additional information as they try to determine optimal locations to drill new wells.

A 3-D seismic survey is one of the most valuable tools used to gain a better understanding of the rock formation below. A seismic shoot is conducted by a contractor whose crew places lines of receivers called ‘Geo Phones’ on the ground to record the sound waves generated by a vibrator truck. The energy travels downward and is reflected back to the surface by the different rock layers. The Geo Phones record the sound waves as they travel back to the surface. As the vibrator trucks move across the surface new seismic lines are created. With the use of advanced software and powerful computer hardware large amounts of seismic data can be processed.

A geophysicist then interprets this information to create a three-dimensional view of the layers of rock below. Underground geologic features then become much easier to identify and target. This information gives other members of the exploration team new data to study. This allows them to map subsurface formations and anomalies and predict where oil or gas may be trapped in sufficient quantities to warrant exploration activities. This valuable data assists in the selection of drilling locations. Once a prospect has been determined to have potential further studies are necessary. Geologists study logs from offsetting wells and construct various maps and cross sections while reservoir engineers determine potential reserves. When a prospect has passed the oil company selection criteria a drill site location is then selected. An Authority for Expenditure or AFE is prepared by a lease operator and sent to non- operators before work can begin. It is a budgetary document listing the estimated expenses of drilling the planned well. This estimate of costs requires approval prior to commencement of drilling operations.

Once the survey has been completed, a stake will be placed where the well is to be drilled. Access roads are created so workers and equipment can get to and from the rig. The site will be cleared and leveled with a bulldozer. For support and permanent positioning of the wellbore the seller and conductor holes are dug and secured into place. The drilling rig and equipment are then trucked to the location unloaded and placed where it will be rigged up. A reserve pit may be excavated to capture drilling fluids, cuttings and mud discharges so they can be recycled or properly disposed. Crew housing facilities, water lines and electricity are brought in for 24/7 operations.

After the rig is erected equipment is moved onto the rig floor, assembled and connected to power sources or pressurized piping systems. Some operators utilize an alternative method of managing returned fluids and solids called ‘A Closed Loop System’ which may reduce or eliminate the need for reserved pits. The Closed Loop System separates the fluids and drilling solids by employing a series of linear motion shakers, mud cleaners, centrifuges and collection equipment to condition the fluids so they can be reused or recycled. The solids or waste is properly disposed off according to state regulations. The hole for the surface casing is then drilled. A drill bit is mounted on the end of the drill pipe as the bit grinds away a mixture of water and additives called ‘Mud’ is pumped into the hole to cool the bit and flush the cuttings to the surface. The pipe and bit are then removed and surface casing is inserted into the hole. Surface casing serves to keep the well bore intact, isolate the freshwater zone from contamination and is the pipe to which the BOP and wellhead are attached. The casing is secured into place by pumping cement through the casing and the shoe at the bottom of the hole. This cement also acts as a barrier to provide a permanent layer to protect the freshwater aquifer. Next, the Blow Out Preventer or BOP is installed on top of the wellhead before the drilling of the well commences. It is usually comprised of an annular preventer; blind ram blind shear ram and the pipe ram.

The BOP units main function is to contain erratic down hole pressures called ‘Kicks’ and the uncontrolled flow of formation fluids quickly and effectively by sealing off the wellbore in several ways. If primary control of the well is lost during drilling or completion, one or more of the BOPs components are initiated to close across part or all of the hole to equalize pressures thereby regaining control of the well. Without the BOP, this underground pressure can force the release of gases, fluids and equipment causing explosion, fire and loss of life. Blowout preventers are critical to the safety of the crew, rig and environment.

At this point using a slightly smaller diameter drill bit and pipe the intermediate section of the hole is drilled through the wiper plug, shoe and cement at the bottom of the hole. Once this section of the hole is drilled the intermediate casing is set, cemented and allowed to cure. Drilling then continues on toward the target depth. Millions of dollars can be spent drilling an oil well. So it is very important to gather as much information as possible at every stage to determine if it makes good business sense to continue drilling and complete the well.

Drill Stem Testing also known as a DST is a procedure used on exploratory oil and gas wells to determine the boundaries and commercial productive ability of a hydrocarbon reservoir. Information gained from a DST includes fluid samples, reservoir pressure, flow rates and formation properties such as temperature and permeability. As the well is drilling, the mud logger takes samples and monitors incoming data. When the mud logger has a good show indicating potential pay, drilling will stop and the pipe and bit are pulled out of the hole. The DST tool is then attached to the bottom of the drill string and lowered into the hole opposite the formation to be tested. One or more expandable seals on the tool called ‘Packers’ are initiated to seal off the zone. A hydraulic valve is then opened in the tool. Once open the fluid then flows into the valve and up the drill string to the surface for evaluation. A typical test is comprised of several alternating formation flow and shut-in periods.

Once the well has been drilled to its target depth, the drill pipe and bit are removed from the hole and a specialized logging crew and equipment are brought on location. The crew assembles a probe which can be several different logging tools connected together. Each tool performs a different kind of measurement of the rock and fluid properties within the geological formations surrounding the well bore. The probe is lowered down into the wellbore on a wire line until the top of the probe is below the target depth. The process is carefully monitored by the well logging crew and the geologists. As the probe is raised back up the hole the various logging tools are activated by computers on the surface that produce a graph called a ‘Well Log’ which represents the geologic properties of the layers of rock. Lining up the logs, adjusting for variations in the surface elevation of each well the geologist can get a good idea of the rock structure and possible presence of hydrocarbons across the area.

Once the well has been logged and deemed a commercial well, the crew inserts the last string of production casing that runs the entire length of the hole and cements the casing in the hole. The cement fills the space between the production casing and the drilled hole called ‘The Annulus’. It also adds stability and strength to the pipe and creates a barrier between the formation and the casing. At the surface the drilling rig is no longer needed. A coil tubing unit or workover rig is brought on location to perforate the targeted zone. A perforating gun is then lowered to the targeted zone; pressure is applied to the coil tubing and perf gun, setting off a charge which shoots holes through the steel casing, cement and out a short distance into the target formation. The perf gun is then pulled out of the hole.

Stimulation is needed on most wells to establish production from the reservoir. Specialized equipment to hydraulically fracture or frack the formation is brought on location. Water, a small amount of chemicals, sand and other province are pumped into the wellbore under extremely high pressure. When the mixture reaches the target zone the pressure forces it out through the perf holes and into the low permeable shale causing it to fracture or crack. This creates a fairway connecting the reservoir to the well. The sand and other province hold the tiny fissures open and allow the released oil to flow to the well bore. This process is repeated in multiple stages to extend across the wellbore. With plugs placed between each stage to maintain pressure and get maximum flow results from the fractured rock. Once the fracking process is complete, the plugs placed between the frack stages are then drilled out to remove any restrictions in the wellbore. The frack fluid also known as ‘Flowback Liquid’ flows back up to the top of the well along with hydrocarbons. The recovered frack fluid is treated and most reused on subsequent hydraulic fracturing jobs. This is done to conserve water and also as a cost savings measure. What is not able to be reused is placed in tanks and then trucked to be properly disposed. The production crew then brings in the work over a unit and rigs it up to prepare the hole for production. The crew runs small diameter pipe called ‘Production Tubing’ inside the production casing string. This serves as the conduit for oil or gas to flow up the well and adds yet another layer of protection to isolate the hydrocarbons from the potable water table.

The next step is to install a permanent wellhead. Most wells at some point in their life will require artificial lift to get the hydrocarbons to the surface. In this case a Pumpjack, oil storage tanks and associated equipment are installed on location.

As one of the many environmental safety measures an earthen berm is built around the production equipment. During the production phase oil is sent from the pump jack to the Heater-Treater for initial processing. The function of the Heater-Treater is to separate the oil from the water and gas. During this process the liquids from the well are heated, the oil separates and floats to the top of the settling water while gases break free and rise to the top of the tank. The gas passes through the mist extractor at the top of the tank and is sent to be stored or flared. The water is removed and stored for further treatment. The oil is sent to the storage tanks to await transport to the pipeline.

During field development, additional wells are drilled on the lease to maximize recovery of reserves. Field development occurs in stages and includes many of the oil companies same teams of geo scientists and engineers who studied and evaluated the data to justify the initial well. Once executive management makes the decision to move forward, the planning phase begins.

Next, additional drilling rigs are brought in along with several service companies to help with construction, build infrastructure and assist the drilling company. An oil well can produce for ten to thirty years during the primary recovery phase. Once production has declined secondary or tertiary recovery methods can be used to extend the life of the well. When the well no longer produces at an economic rate the final steps in a wells life cycle are abandonment and reclamation. The wellhead and associated equipment are removed, the wellbore is filled with cement and the well capped and mark. The area is reclaimed and the lease is relinquished back to the landowner.

Oil and gas exploration and production is a complex but vital endeavour. The energy and products created from crude oil are endless and essential to our everyday way of life. Without it roads, railways and the skies would be empty. Construction, manufacturing, technology and food delivery would come to a standstill. Oil and gas and the many technical and skilled people involved in drilling and oil well are crucial resources we are dependent on each and every day.

Reference 

YouTube. (2018). Overview Of Drilling Process. [online] Available at: https://www.youtube.com/watch?v=2QlH2fhWEAc [Accessed 15 Oct. 2018].

The post Overall Drilling Process Video Training with Full Video Transcript appeared first on Drilling Formulas and Drilling Calculations.

Leg punch through which is one of the biggest dangers of a Jack Up is happened when a jack up leg or more legs rapidly penetrates into formation underneath a spud can(s). This will result in damage in legs, loss of balance of a rig, and potential harm people life.  Whether higher environmental loads or larger water depths, this increases demand on Jack Ups, leads to higher elevated weights, and creates more pronounced consequences of a punch. As depth increases, so does a typical soil’s bearing capacity. Soil strength also sees a rapid reduction when a soil layer is underlain by a weaker layer. The weaker soil eventually gives way as the spud can reaches the interface and the jacking system can’t cope with the speed at which the support of the leg moves downwards; the leg isn’t able to maintain the hull level. The hull then sways after it rotates and bends the legs. Relative to the supports, a weight shift occurs and to maintain equilibrium the required footing reaction increases. This process will only end when any hull buoyancy (from the hull now in the water) or the soil’s bearing capacity allows an equilibrium to be reached.

Figure 1 – Soil Bearing, Apvandenberg.com. (2008).

Punch through can occur in Jack Ups of all designs, and the damage normally reaches jacking units, braces, and chords. When a punch through occurs, the resulting accidental loading can cause a shearing of the chord, bucking of the braces, and punching shear and joint damage. The actions before, during, and after the punch through will entirely depend on the extent of the damage (and the size of the punch through). Since punch through is serious occurrence, high-quality management is essential. Some level of risk can be minimized with modern rigs since they offer effective punch through management systems and a better guide design.  One example is shown in figure 2 which is Maersk Victory Punch Through Incident in 1996,

Figure 2 – Maersk Victory Punch Through Incident in 1996, Members.home.nl. (2012)

For a given amount of ‘leg run’ (leg bending as an indicator of seriousness), there are various factors that will determine the consequences of a punch through. For example;

• Depth of Water – Leg bending tends to be more severe in deeper water
• Leg Spacing – Leg bending will generally decrease with greater leg spacing
• Elevated Weight – Increased leg bending will result from higher elevated weight (the amount of preload)
• Air gap – Leg bending increases with a larger airgap because it takes longer for buoyancy to activate and aid the recovery

To reduce the extent of a punch through, there’s a process called ‘Swiss Cheesing’. As long there’s regression in the soil strength versus depth (penetration) curve (assuming it’s over a large span), holes can be drilled through the critical soil layers in an attempt to decrease soil strength. If done correctly, the legs will reach past the critical depth in a more controlled way (and at a reduced load level). This process is most effective where the regression is close to the maximum footing reaction of the Jack Up.

References

Apvandenberg.com. (2008). April 2008: Partnership of A.P. van den Berg and Keppel FELS – A.P. van den Berg. [online] Available at: https://www.apvandenberg.com/news-archive/april-2008-partnership-of-ap-van-den-berg-and-keppel-fels [Accessed 29 Oct. 2018].

Members.home.nl. (2012). Maersk Victory Punch-Through – Oil Rig Disasters – Offshore Drilling Accidents. [online] Available at: http://members.home.nl/the_sims/rig/m-victory.htm [Accessed 29 Oct. 2018].

Mitchell, R.F., Miska, S.Z. and Aadnoy, B.S. (2012) Fundamentals of drilling engineering. Richardson, TX: Society of Petroleum Engineers.

Bork, K. (1995). The rotary rig and its components. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

Davis, L. (1995). Rotary, kelly, swivel, tongs, and top drive. 1st ed. Austin: Petroleum extension service. Division of continuing education. University of Texas at Austin.

The post What is Leg Punch Through (Rapid Penetration) for Jack Up Rigs ? appeared first on Drilling Formulas and Drilling Calculations.

Primary well control is the most important barrier while drilling and completing any wells so it is imperative to ensure that the primary well control is effectively maintained.

When various precautions and procedures have been followed, effective primary well control can be achieved. These procedures can be seen below;

Tripping Procedures

 Using a trip sheet (an accurate log), it is possible to maintain tripping both in and out of the well. A trip sheet can help to record the volume of mud that not only enters the well but also that is displaced when tripping. During tripping, the changes in mud volume can be measured using a calibrated trip tank.

For any steel removed, a specific amount of mud is entered into the well when the tripping pipe or drill collars from the hole. To ensure proper well monitoring, tripping may need to be stopped whenever the volume of removed steel significantly outweighs the volume of mud required. After stopping, consideration should also be made towards returning back to bottom in order to condition the mud (and find the cause of the issue). At all times, the drill floor should have the required crossover subs and a full opening safety valve readily available.

Mud Weight (Mud Density)

To control the well, the correct weight needs to be maintained and this can only occur when mud entering/leaving the well is weighed. The shaker man is normally in charge of this process every 15 – 30 minutes or so; however, this’ll completely depend on company policy and the drilling operation in question.

Flow Checks

To ensure well stability, flow checks can be carried out regularly. To remove ECD effects, the well should be checked with the pumps off. Usually, when a trip takes place in certain locations, flow checks will be performed. These locations include the bottom, the casing shoe, and before the BHA is pulled into the BOPs.

Trip Margin 

To compensate for the ECD loss, the Trip Margin is an overbalance; during a trip out of the hole, this will also help to overcome swab pressure effects.

Mud Logging

If available, another important process for well control is mud logging. With a mud logging unit, there will be opportunities for gas analysis, pore pressure trends, gas detection, recording flow line temperatures, cuttings density, recording penetration rates, and recording mud densities (both in and out).

Short Trips/Wiper Trips

Before pulling out of the hole a short trip, some circumstances will require a consideration of either five or ten stands. From here, the well will circulate as expected and the mud can be carefully monitored.

Pumping a Slug of Heavy Mud

Often, this process can be used so the pipe can be pulled dry (and to monitor the hole accurately during the trip). After pumping slug, a driller must wait until slug stop falling down by monitoring a well via a trip tank. The flow return should be completely stopped prior to continuing pulling out of hole. Otherwise, a record in a trip sheet may be off and it can cause confusion while monitoring a well.

Alarms

The flow line recorder and pit level recorder need to be set at appropriate values and checked regularly; this includes both the high and low settings.

Communication

Despite all the processes listed above, good communication will still be important. The logging unit and driller must always be informed when mud is transferred to the active system.

References

Coleman, S. (2018). Well Control Quiz Online. [online] Well Control Quiz Online – Test Your Well Control Knowledge for Free. Available at: http://wellcontrolquiz.com/ [Accessed 2 Aug. 2018].

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post How To Ensure Effective Primary Well Control appeared first on Drilling Formulas and Drilling Calculations.

Lost circulation whole mud (whether to depleted reservoirs or to natural/induced fractures)is one of biggest causes of well kicks. In the wellbore, fluid levels can decrease and this lowers the hydrostatic pressure. Once hydrotatic pressure is less than formation pressure, it will cause a flow from the formation in permeable zones. Figure 1 illustrates loss of fluid level into a weak zone which will lead a well control incident if a wellbore is not filled up on time with correct mud weight.

Figure 1 – Lost Circulation in Drilling Leading to a Well Control Situation

Lost circulation can happen for a number of reasons and we’ve detailed four possibilities below;

Annular Circulating Friction

When drilling near the fracture gradient of the formation with a heavy mud, the pressure added by circulating friction should always be considered. Especially in small holes with a large drill pipe or with stabilizers inside the protective casing, this added pressure can be significant. In many cases, the pumping rate will need to be reduced to then decrease the circulating pressure. Often, where high gel fluids are used, the problem quickly becomes acute when attempting to break circulation in this way.

Entering the Hole Too Quickly

When the drill pipe and bottom assembly are lowered too quickly, this can also cause a loss of circulation (this includes the reamers, drill collars, and bit). Although somewhat similar to swabbing, it’s effectively in reverse as the weakest formation is targeted by the piston action as it forces the drilling fluid into new positions. If the pipe is much larger than the hole and the string has a float in it, the problem is made even worse. Whenever weaker formations have been exposed, or even if heavy mud has been employed to counter high formation pressure, particular care will need to be taken when running pipe into the hole. Many commercially available programs now exist for surging calculations which makes the whole process easier than ever before.

Balled-Up or Sloughing Tools

To restrict the flow of fluids in the annulus, it’s possible to partially plug the annulus by sloughing shale. By imposing a backpressure on formations, a breakdown can quickly occur as long as the pumping continues. Stabilizers and other large drillstring components are common locations for annular plugging; the chances of encountering this type of lost circulation can be reduced with efforts to reduce balling. Read more details about balled up bit below.

Balled up Bit

Excessive Mud Weight

Finally, fluid levels in the hole can decrease and circulation can be lost whenever the fracture gradient (of the weakest exposed formation) is outweighed by bottomhole pressure. Why? Because the effectiveness of the hydrostatic head will decrease when acting against those formations that haven’t broken down. Assuming the mud levels drop severely, the BHP can fall below formation pressure and the well will start flowing.

Lost circulation should be avoided at all costs; if returns cease, measured volumes of water should be pumped into the hole and this should minimize the loss of hydrostatic pressure. For the Drilling Site Supervisors, they need all volume measures so they can calculate the weight of mud required to support the formation before fracturing occurs. After gaining returns, the well will need to be checked to ensure it isn’t flowing alone.

We hope this article help you prevent lost circulation in the future. Please feel free to share your thought in the comment box below.

References

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post What Cause Lost Circulation in Drilling Leading to a Well Control Situation appeared first on Drilling Formulas and Drilling Calculations.

Known as an underbalanced condition, this occurs when, in the wellbore, formation pressure is higher than the hydrostatic pressure and this lead to a well control situation. To overbalance formation pressure, the required hydrostatic pressure is normally provided through an adjustment in drilling fluid density. Hydrostatic pressure loss can occur for a number of reasons;

• ECD loss
• Surface drilling fluid dilution
• Cement density reduction
• Drilling process releasing formation fluids
• Weighting material movement from mud cleaning equipment
• Drilled cuttings or mud weighting materials settling

Since a reduction in the density of mud returns is sometimes happened, most wells are designed to have sufficient overbalance to encounter the small reduction of mud density and this should prevent a kick. However, if there is significant mud weight reduction, an investigation shall be performed to find any root cause and provide any preventive actions.

Causes of mud weight reductions are as follows;

1. Surface Drilling Fluid Dilution

What potential issues could initiate a kick? One possible problem could be, in the surface pits, a dilution of drilling liquid (normally accidental with the mud column receiving drilled-up, low-density formation fluids or make-up water).

Unfortunately, insufficient fluid density can be caused by poor pit discipline. To ensure the maintenance of fluid density for the fluid that’s pumped downhole, diligence is essential at all times. Without diligence, a leaking valve may not be noticed and this may create extra water. Elsewhere, it’s possible to open the wrong valve (pump suction manifold) and this leads to a tank of light weight fluid being pumped.

2. Cuttings or Mud Weighting Materials Settling

A reduction in mud density can also be caused by the settling of solids (in the mud settling); the same is also true when the bottom of the hole is filled with cuttings that have settled. When either of these occur, hydrostatic pressure reduces in the wellbore and this can cause a kick in the well.

When mud weighting materials settle in the wellbore, this is called ‘barite sag’ and it can occur in vertical wells (especially during non-circulation periods); this being said, it’s more common in extended and highly-deviated reach wells. Most experts believe barite sag can never be eliminated but there are various management techniques including pipe rotation maintenance, good mud design, and low annular velocity avoidance.

3. Releasing Formation Fluids (Influx) into Drilling Mud

It’s incredibly hard to avoid mud contamination when drilling through a formation. if the formation being penetrated is overbalanced, contamination can still occur. From the cuttings, this mud can combine with gas called ‘drilled gas’. The rate at which the drilled gas enters the mud will depend on formation porosity, rate of penetration, pressure, hole diameter, and gas saturation.

When a permeable formation with higher pressure than the pressure exerted by the mud column is drilled, this can cause a kick. When the mud has large amounts of gas entering into a wellbore, average mud density will fall and hydrostatic pressure from the drilling fluid will also reduce.

Over the years, the industry has learned that shallow gas blowouts in offshore environments can be caused by excessive gas cutting in shallow holes. Therefore, shallow holes must have controlled ROP. In order to disperse all gas in the mud, maintenance is also important for high pump output; this should keep variations in mud density to a minimum.

From cuttings or swabbing, the wellbore can often be invaded by salt water and oil which can cause a kick after decreasing the average density of the mud. Of course, liquids (oil and water) are heavier than gas and the average density isn’t affected as greatly for the same downhole volumes. When circulating them out, little expansion (or none at all) will occur as liquids are only slightly compressible. Compared to mud cut by gas, the decrease in bottomhole pressure is significantly greater when saltwater or oil invasions are measured at the surface since this causes a given mud weight reduction. When cut by a liquid, density reduction throughout the mud column can be more uniform.

4. Cement Density Reduction 

Often, kicks can occur while mixing and pumping cement.Why does this occur? Typically, it happens when hydrostatic pressure of the fluid column reduces in the wellbore. Although most common cement density reduction is happened by improper mixing, there’s also a potential of cement density being cut by gas or formation water and this contaminates the slurry. If hydrostatic pressure reduces below formation pressure, the kick will be influx into the well. It’s important to find the cause which is normally one of the following;

• A loss of hydrostatic pressure can often result from lost circulation when the cement density is higher than normal.
• In many cases, there has been a failure in float equipment and this allows drilling fluid to U-tube up the casing. Within the annulus, there’s insufficient hydrostatic pressure.
• Normally, a flush or spacer will be pumped ahead of the cement; without the right density, the well can start to flow.
• It’s important to pay attention to right-angle and time, manner time, and the percentage of free water with cement design.

During cementing operation, the well needs to be monitored closely through every single phase. Until you can be absolutely sure there’s no danger of the well flowing, the BOPs should never be nippled down.

Additionally, when cement is in transition period (forming the bond), it will lose some hydrostatic pressure because cement becomes solid phase therefore water in the cement will provide hydrostatic pressure. During the cement transition period, there is a chance that hydrostatic pressure is less than formation. More details can be found here – Cement Transition Period in The Oil Well Can Cause Well Control Situation

5. ECD Effect Loss

Equivalent Circulating Density (ECD) lose when there is no flow. To make a connection, the pumps need to be shut down and this reduces bottomhole pressure until it eventually matches static bottomhole pressure (hydrostatic pressure). At this point, there is no annular friction so ECD is equal to hydrostatic pressure. When the ECD effect is lost, it’s much easier for fluids and formation gases to enter the wellbore. If the well is at slightly underbalance condition, formation gas/fluid cannot enter into a wellbore while drilling because ECD is higher than formation pressure. However, when pumps are off, gas can flow into the well while making up a connection. You can see a gas peak showing at similar stroke so this is called a ‘connection gas’. Practically, the trip margin should always be maintained to a level equal to the ECD value (at least). This way, bottomhole pressure can be maintained just above the formation pressure when the pumps are shut down. Too much connection gas will lead to excessive gas cutting which, in turn, will cause a kick by reducing bottomhole pressure.

References

Coleman, S. (2018). Well Control Quiz Online. [online] Well Control Quiz Online – Test Your Well Control Knowledge for Free. Available at: http://wellcontrolquiz.com/ [Accessed 2 Aug. 2018].

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post What Cause Insufficient Mud Weight Leading to a Well Control Situation appeared first on Drilling Formulas and Drilling Calculations.

The alertness in determining early possible kick indicators in well control is of the utmost importance to prevent a well control incident. Careful observance and positive reaction to these signs will keep the well under control and prevent the occurrence of a well control situation.

The various signs that have been recorded as early warning indicators are not consistent in all situations. The signs however may have to be used collectively as one indicator may not accurately provide the warning of getting into an underbalanced situation. Even though the series of signs may change between wells, early warning indications can be found from the following list.

• Increase in drilling rate of penetration.
• Increase torque and drag.
• Decrease in shale density.
• Mud property changes.
• Increase in cutting size and shape.
• Increase in trip, connection and/or background gas.
• Increase in the temperature of the return drilling mud.
• Decrease in D-exponent.

Increase in Rate of Penetration When drilling ahead and using consistent drilling parameters, as the bit wears, a normal trend of decrease penetration rate should occur. If the differential pressure between the hydrostatic pressure of the drilling fluid and formation pore pressure decreases, an increase in the drilling rate occurs as the chip hold down effect is reduced.

A general and consistent increase in penetration rate is often a fairly good indicator that a transition zone may have been penetrated. This change in rate of penetration is known as a Drilling Break (Figure 1). A rapid increase in penetration rate may indicate that an abnormal pressure formation has been entered and an underbalance situation has occurred.

Figure 1 – Drilling Break

Increased Torque and Drag

Increased drag and rotary torque are often seeb when drilling into overpressured shale formations due to the inability of the underbalanced mud density to hold back physical encroachment of the formation into the wellbore.

Drag and rotating torque are both indirect and qualitative indicators of overpressure. They are also indicators of hole instability and other mechanical problems. Torque and drag trend increases often indicate to the driller that a transition zone is being drilled. Up drag and down drag as well as average torque figures should be recorded on each connection. These trends are valuable when comparing other trend changes.

Example of relevant information can be found on the following articles;

Hydro-Pressured Shale Causes Stuck Pipe

Geo-Pressured Shale Causes Stuck Pipe

Decrease in Shale Density

The density of shale normally increases with depth, but decreases as abnormal pressure zones are drilled. The density of the cuttings can be determined at surface and plotted against depth. A normal trend line will be established and deviations can indicate changes in pore pressure. Shale density can be measured by using a mud balance so please see more detail in this article, Bulk Density of Cuttings Using Mud Balance.

Increase in Cutting Size and Shape

In transition zones or in abnormally pressured shale’s (sandy shale’s and bedding sand streaks) the shale’s break off and fall into hole because of under balanced condition (pore pressure greater than mud hydrostatic pressure). Water wetting may further aggravate this problem.

Changes in the Shape of Shale Cuttings can occur as an underbalanced situation is developing. The particles are often larger and may be sharp and angular in the transition zone. Extra fill on bottom may coincide with the trend change. Severe sloughing will often cause changes in pressure and stroke relationship. Hence, it is very imperative to frequently check cutting coming over shale shakers (Figure 2) to monitor a wellbore behavior.

Figure 2- Always check cutting size over shale shakers

Normally pressured shale’s produce small cuttings with rounded edges and are generally flat, while cuttings from an over pressured shale are often long and splintery with angular edges. As reduction of hydrostatic differential between the pore pressure and bottomhole pressure occurs, the hole cuttings will have a greater tendency to come off bottom. This can also lead to shale expansion causing cracking, and sloughing of the shale into the wellbore. Changes in cuttings shape and cuttings load over the shakers needs to be monitored at surface.

Mud Property Changes

Water cut mud or a chloride (and sometimes calcium) increase that has been circulated from bottom always indicates that formation fluid has entered the wellbore. It could be created by swabbing or it could indicate a well flow is underway. Small chloride or calcium increases could be indicative of tight (nonpermeable) zones that have high pressure.

In certain type muds, the viscosity will increase when salt water enters the wellbore and mixed with the mud. This is called flocculation because the little molecules of mud solids, which are normally dispersed, form little “groups” called flocs. These flocs cause viscosity and gel increases. In other type muds you might see a viscosity decrease caused by water cutting (weight decrease). This is true when operating with low pH salt saturated water base muds.

In oil based mud, any water contamination would act as a “solid” and cause viscosity increases. Gas cut mud would be fluffy and would have higher viscosities (and lower mud weight). It is essential to know that the Trend changes are more important than the actual Value of the change.

Increase in Trip, Connection and Background Gas

Return mud must be monitored for contamination with formation fluids. This is done by constantly recording the flowline mud density and accurately monitoring gas levels in the returned mud.

Figure 3 – Gas Monitoring at a Return Line

Gas cut mud does not in itself indicate that the well is flowing (gas may be entrained in the cuttings). However, it must be treated as early warning of a possible kick. Therefore pit levels should be closely monitored if significant levels of gas are detected in the mud. An essential part of interpreting the level of gas in the mud is the understanding of the conditions in which the gas entered the mud in the first place. Gas can enter the mud for one or more of the following reasons:

• Drilling a formation that contains gas even with a suitable overbalance.
• Temporary reduction in hydrostatic pressure caused by swabbing as pipe is moved in the hole.
• Pore pressure in a formation being greater than the hydrostatic pressure of the mud column.

Gas due to one or a combination of the above, can be classified as one of the following groups:

Drilled Gas When porous formations containing gas are drilled, a certain quantity of the gas contained in the cuttings will enter the mud. Gas that enters the mud, unless in solution with oil base mud and kept at a pressure higher than its bubble point, will expand as it is circulated up the hole, causing gas cutting at the flowline. Gas cutting due to this mechanism will occur even if the formation is overbalanced. Raising the mud weight will not prevent it. It should be noted that drilled gas will only be evident during the time taken to circulate out the cuttings from the porous formation.

Connection Gas Connection gases are measured at surface as a distinct increase above background gas as bottoms up occurs after a connection. Connection gases are caused by the temporary reduction in effective total pressure of the mud column during a connection. This is due to pump shut down (i.e. loss of ECD) and the swabbing action of the pipe. In all cases, connection gases indicate a condition of near balance. When an increase trend of connection gases are identified, consideration should be given to weighting up the mud before drilling, operations continue and particularly prior to any tripping operations.

Trip Gas Trip gas is any gas that enters the mud while tripping the pipe with the hole appearing static. Trip gas will be detected in the mud when circulating bottoms up after a round trip. If the static mud column is sufficient to balance the formation pressure, the trip gas will be caused by swabbing and gas diffusion. Significant trip gas may indicate that a close to balance situation exists in the hole.

Change in the Temperature of the Mud Returns

The temperature will normally take a sharp increase in transition zones. The circulating rate, elapsed time since tripping and mud volume will influence flowline temperature trends. The temperature gradient in abnormally pressured formations is generally higher than normal. The temperature gradient decreases before penetrating the interface and therefore marked differences can give and early indication of abnormal pressures. This is usually a surface measurement which has a tendency to be influenced by operating factors. Figure 4 shows plots of temperature increase while penetrating an abnormal pressure formation.

Figure 4 – Increase in Flow Line Temperature (Slide Player, 2016)

Decrease in D–Exponent

The D-exponent will be plotted by the well loggers and maintained current at all times. This value was introduced in the mid sixties to calculate a normalized penetration rate in relation to certain drilling parameters.

The “d-exponent” described from the equation below:

d = log (R ÷ 60N) ÷ log (12W ÷ 1000D)

Where; R = penetration rate in feet per hour

d = exponent in drilling equation, dimensionless

N = rotary speed in rpm W = weight on bit in kilo pound

D = bit size in inch

** Note: this equation is is valid for constant drilling fluid weight.

The D-exponent may be corrected and normalized for mud weight changes and/ or ECD (equivalent circulating density) by the following:

dc = d x normal pressure (ppg) / mud weight or ECD (ppg)

A plot of Dc-Exponent versus depth in shale sections has been used with moderate success in predicting abnormal pressure. Trends of Dc-exponent normally increase with depth, but in transition zones, its value decreases to lower than expected values which indicate a possible high pressure zone. Figure 5 demonstrates a Dc-Exponent plot showing an abnormal pressure ramp.

Figure 5- Dc-Exponent Plot

References 

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

Slideplayer.com. (2016). Lesson 21 Prediction of Abnormal Pore Pressure – ppt video online download. [online] Available at: https://slideplayer.com/slide/8617461/ [Accessed 23 Jan. 2019].

Drilling Formulas and Drilling Calculations. (2009). D Exponent Calculation. [online] Available at: http://www.drillingformulas.com/d-exponent-calculation/ [Accessed 23 Jan. 2019].

The post Possible Kick Indicators in Well Control appeared first on Drilling Formulas and Drilling Calculations.

During well kill operation, crews should always be vigilant since complications can actually occur at any stage. If there’s a discrepancy in the kill plan, it needs to be noted immediately. For example, pressure gauges may stop working; they therefore should be monitored carefully. If there’s a failure, back-up gauges need to be made available during a well control operation.

In this article, it will describe common problems and complications during well kill operation which are plugged bit nozzle, plugged choke, choke washout, pump failure and string washout.

Plugged Bit Nozzle

When the drillpipe pressure increases, without a huge change in choke pressure, this suggests a plugged nozzle in the bit. To reduce drillpipe pressure to a comfortable circulating pressure, there’s normally a temptation to open the choke by the operator. However, this will lead to a bottomhole pressure decrease after a similar drop in choke pressure.

If the plugged nozzle is detected during first circulation of driller’s method, a choke operator should record new circulating pressure without changing any position of choke. If the problem is seen during second circulation of driller’s method, you can maintain casing pressure (choke pressure) until kill mud weight reaches a bit, then maintain the lasted drill pipe pressure. In another scenario during kill the well using wait and weight method (engineer’s method), if this situation occurs, you need to wait to get new stabilized circulating pressure and recalculate a new pressure schedule.

Elsewhere, the packing off around the BHA can also cause drillpipe pressure increases. As a result, circulating pressures are likely to both increase and fluctuate. To remove the problem completely, the drillstring needs to be reciprocated if possible. Unfortunately, a rapid increase can be experienced in drillpipe pressure when the bit becomes totally plugged (despite very little change in choke pressure). When this occurs, the string needs to be perforated if the problem isn’t cleared by the increased drillpipe pressure; to re-establish circulation, the perforation needs to be as close to the bit as possible. A circulating sub should be run above the bit or core barrel; this is considered good practice and is especially important in critical hole sections.

Plugged Choke

When choke pressure and drillpipe pressure increase simultaneously, this suggests a plugged choke situation. Whenever the annulus is loaded with cuttings, it’s normal to expect some plugging of the choke.

When this happens, the first step should always be to open the choke; this is important not only to clear the restriction but also to avoid over-pressuring. If unsuccessful, the pump should be stopped as quickly as possible. It is advised to switch to an alternate choke before then bleeding the excess pressure in the well; if done correctly, the displacement can then be restarted as normal. If cuttings plug the choke, over-pressuring can be prevented by displacing a kick at a slow circulation rate. With this in mind, in critical conditions, circulation rates should be minimized when there’s likely a large volume of cuttings in the annulus.

Choke Washout

Since a sudden cut is incredibly unlikely in the choke, there’s not really a common symptom that it’s about to occur. Over time, the choke will wear so it’s important to gradually close it in and this should allow for circulating pressure maintenance. If the operator is having to do this to maintain circulating pressure, the pit volume should be checked just in case lost circulation is a problem. If there’s no loss of circulation, this suggests a worn choke. Even with the choke fully closed, there could come a point where a suitable circulating pressure is difficult to maintain. Before it gets to this stage, the worn choke should be repaired after switching the flow to a different choke.

Pump Failure

When there’s a failure at the fluid end, a common indicator is irregular rotary hose movement along with erratic standpipe pressure. In many cases, a decrease in circulating pressure will precede this. If an operator suspects pump failure, the well should be shut-in and the pump stopped. With the second rig pump (or the cement pump, if necessary!), the displacement should be continued. After this, there should be immediate repairs to the pump.

String Washout

When a washout in the drillstring occurs, the most common indication will be a standpipe pressure decrease (the choke pressure will remain unchanged). In this event, the well should be shut in and the pump should be stopped. Through drillstring manipulation and extended circulation, the washout can grow in size so this needs to be prevented.

The biggest risk in these circumstances is a washout occurring close to the surface. If this happens, displacing the influx from the hole will become difficult and unlikely; it will only be possible when the influx is above the washout. If near the bottom of the well, displacing the kick may be possible. Of course, this comes with certain risks including the parting of the drillstring with continued circulation. If the pump is restarted, it’s important to re-establish the circulating pressure no matter the washout depth. If the original circulating pressure is maintained at the standpipe, this could cause excessive downhole pressures. Through a washout, the circulation may be contained for extended periods so the circulating pressure should be re-established periodically.

String Washout

Summary of pressure responses of each complication is shown in the table below.

References  Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post Common Problems and Complications During Well Kill Operation appeared first on Drilling Formulas and Drilling Calculations.

As you know that there are so many people who really want to work in the oilfield. However there are only few people who have a chance to get interviewed because they write the good resume. I’ve been working in this oilfield business for years and I know that the chances of your resume being chosen out of a stack of job seekers are getting slimmer. Out of 20 resumes, only two or three candidates will be chosen by employers for an interview. As the number of resumes per job opening increases, the odds against landing the interview are also increasing.

With leading resume writing skills and techniques, you can turn the odds in your favor and get the interviews.

Employers always look for the resumes that jump out at them. They are looking to be impressed by skills, qualifications, and more! By reading your resume, they want to be able to feel comfortable that YOU are the right person for the job. With the right resume, they will choose you before ever setting eyes on you!

Tall order, right? Absolutely! But with the right resume writing skills, you can fill it!

The very first step to landing that ideal job is to write a resume and cover letter that are compelling. Without those two key forms of introduction, there most likely will not be a first interview!

The First Important Step to Professional Resume Writing for Oilfield

Your resume places you in the front lines when job hunting. It becomes your calling card. It is not about compelling drama or clever prose; it is a few simple pages, expertly written, containing information that is all about you. Importantly, that information should contain the attributes, or keywords, that the employer is seeking – in qualifications, skills, and personality.

Your resume will either place you front and center where all the good jobs are or it will not – there is no middle ground. To ensure you get the attention of the hiring manager, this series shows you how to:

Open Job Doors

For the serious job seeker, this “Oilfield Resume Series” will help you open doors. This will be your personal and comprehensive guide to everything you could ever hope to know about conquering the never ending resume and cover letter paper trail.

Your resume writing skills will become well honed and your resume will be fine tuned. You will learn to sell yourself with simple, yet effective, words. Your resume will not be relegated to the bottom of any pile – it will be placed where it belongs at the very top!

You will write a resume that will rival any resume written by a top-notch professional resume writer.

Let’s get started!

Effective Resume and Cover Letter Writing For Oilfield Jobs

To begin writing resumes that work in today’s market, make a decision to discard any former knowledge learned about the “rules” of resume and cover letter writing. Many people have become stuck in “bad” resume writing habits from a time gone by.

It is almost a certainty that since you last wrote your resume, much has been learned and even more has changed. Every day, very creative people are adding to their resume and cover letter writing arsenal. Can your resume compete? Not unless it has been updated to today’s standards. You would not enter the Grand Prix with a 1990s racing car. Do not enter the job market with an outdated resume!

The oilfield resume series is chock full of the most recent and cutting-edge resume and cover letter writing techniques, culled from writing professionals and employment experts.

What Is A Resume and Why You Need A Good One?

Building a resume is about creating a persuasive tool that communicates all about YOU. In an easy-to-read format, a resume provides a prospective employer with an outline of your education, work experience, and accomplishments. When it does the job right, you win an interview.

Your resume will be targeted to a specific employer and job, and show your suitability for the desired position. This position will be a goal you wish to achieve. In the resume, you will be able to show how and why you are the best candidate for this position. It will show you are uniquely qualified and should be chosen.

Your resume does not simply provide a prospective employer with your work history. It communicates loudly and clearly that you have the credentials needed to be a complete success in this new position or career.

Your resume should attract immediate attention. The reader will want to pick it up and read it top to bottom. Interest will be stimulated. An interview will be arranged.

Why update your resume?

A resume written 10 years ago would be overlooked by prospective employers in today’s online job search market. Neither the style, format, or content would capture attention, through an electronic or manual job search.

An employer can have hundreds of boring resumes to pour through. To capture the hiring manager’s eye, your resume must really pop out! To pop out, it must use the latest resume writing and formatting techniques

Your resume must impress within the first important seconds or it will not impress at all. Employers will quickly scan all resumes and then grab for those that catch their eye best.

To write a really effective resume, you will use powerful statements that will impress. This is very important, but, you do not want to oversell! There is a very fine line here and you will learn all about it.

Powerful statements alone will not sell you. They must contain the keywords the employer is searching for in a more efficient electronic search engine. These words have to be presented in statements that impress.

Above all, you will make honest statements about yourself. They will be strong statements and 100% true, or they will not be effective at all.

Just as you would sell any product that you believe strongly in, you will learn to sell the product that is you! Once you have learned to do this, you will find that you will get a better response from a prospective employer than other prospects do and even those with better credentials. It is all in how you market your product!

The New Resume Writing Rules

For years, we have been told that to be the most effective, a resume format should be only one page. This just does not apply any longer! Today’s resume is creative and unique.

Aside from the most essential and key elements, the perfect resume reflects the personality and needs of the job seeker and is not some cookie cutter rendition of what is “acceptable and expected.” New approaches to language selection and use, including search engine optimization, will ensure your resume grabs the hiring manager, offline and online.

Standards in resumes and cover letters have changed dramatically. Effective resume writing not only requires new techniques. The resume will stand out as unique only so far as the job seeker has the creative expression and know-how to pull it off! Therein lies the difference. Every day, employers read all of the standard resumes. They are required to go through each and every one! But, which one will catch their eye?

Resume formatting has advanced, too. When you consider that your resume will be your own personalized form of marketing yourself, you will be motivated to apply all manner of unique communication and expression modes to creating a resume, including a compelling design.

Again, so long as the essential elements are included in each resume and cover letter, you are at complete liberty to make certain that your resume will impress and with a bang!

Just how, exactly, does one do this?

First, it will take only an hour of your time to learn about the most basic but proven principles involved in writing a highly effective resume and cover letter. Once you have this down, the creative expression can begin!

Your primary goal in writing your resume and cover letter is to be noticed among the many. You want to stand out as not just a good candidate but as “the” candidate with the perfect fit for the job you want.

When you are motivated to distinguish yourself through a well written resume, you will rise to the top of the heap of 100 other resumes not written as well as yours. The odds will be in your favor. Your salvation here is in writing a resume that will compel a perspective employer to notice your credentials. If you can master this technique, you will prosper in the job market.

See you in the next chapter soon….

The post Introduction to Oilfield Resume Series (Oilfield Resume Ep1) appeared first on Drilling Formulas and Drilling Calculations.

In this article, it will describe about important elements to create a perfect resume for oilfield employers. Let’s get started.

Developing a Resume Outline

Now that you have organized your career goals, career path, and the professional and personal attributes that make you special, you are ready to write a resume outline. Your resume will contain:

• Your contact information (i.e., name, address, phone, email address, and website address)
• A defined job objective
• A work history
•  Educational history
•  Affiliations
• References

Now that you have a resume outline, you are ready to brainstorm content ideas.

Time to Start Writing a Resume

Wow the Employer

First of all, who are you writing this resume for? Your prospective employer will be the one who oversees the day-to-day operations of the company you want to join.

They make the hiring decisions and they are entirely invested in ensuring that you are the right one for the job. This person will care about whether or not you can do a good job for that company and so this is the one you are writing your resume for. ??

You want to be sure that you are the right candidate for the job. You want to be sure you know everything there is to know about this company. You want to understand exactly which qualities are needed to be the right candidate for this job.

You want to be sure you are not a good candidate for this job, but, that you are the best candidate for this job.

Creating the Ideal Job Candidate Description

This is the time to put pen to paper and to clearly lay out what your prospective employer is looking for in an ideal candidate. You need to be able to solidify what it is that you bring to the table, even before you begin.

Jot down every fine point about your training and experience, your unique characteristics, special talents, even your attitude – everything that shows you are the most qualified for the job you seek.

If you are new to the job market, be creative and draw on your upbringing, life exposure and anything that can account for your unique experience and qualities.

You will begin to be able to connect the dots during this process. Simple statements will turn into sentences and sentences into paragraphs. Keep this information in a safe place. You will use it later to be incorporated into your resume and cover letters.

Writing Resume Content That Sets You Apart

Your resume should be impactful. Your best experience and attributes should jump out at the reader. The prospective employer should immediately grasp your meaning and have a good idea of what you have to offer in the first scan, before reading entirely through it.

Your goal should be to write a resume with no filler. You will only highlight your best accomplishments, and they will be expertly conveyed through the use of strong, clear wording and phrases that are descriptive and colorful. Your resume writing should persuade and cause your employer to want to know more. You want your employer to feel compelled to bring you in for the interview.

Following items are the resume writing content techniques used in resumes that get interviews:

• Use powerful words and statements that will convey a message of impressive credentials and experience. Show you will get the job done better than anyone else.

• Write about your qualifications through clear statements about what you have accomplished. Do not bore them with long-running lists of your potential, talents, or previous job responsibilities.

• Show the exact results of your targeted accomplishments. Make good use of adjectives to show the extent of your skills and experiences. This will show you are results-oriented.

• Write concisely and keep to the point. Be as direct as possible and avoid complex sentences. Use short and direct sentences. Eliminate all repetition.

• Do not use several examples when one example has the same impact. Avoid trying to impress by using larger words.

• Use good language and style variety by offering short and punchy sentences along with sentences that are longer.

• Do not repeat a power verb within the same paragraph.

• Punctuate throughout for easy reading.

• Use professional grade printing and paper to create a professional resume, you should

Elements of A Resume That Will Impress The Employers

The primary elements of an ideal resume contain powerful and assertive statements about your talents, characteristics and accomplishments. No need to be shy. You are going for the gold so sell yourself with all that is in you!

The secondary element of an ideal resume will show “you know your stuff” and know it well! This will be proven by education, experience, work history and any other relevant affiliations that show the prospective employer that you are a person of substance and not only of design.

Keep in mind that the more standard resume is simply a chronological account, a very boring read for most people, and hiring managers will not give it a second glance. Write your resume to be interesting and even impressive, and then watch as your phone rings for that important interview!

You will write a resume that does much more than just inform; you will write a resume that compels a hiring manager to action! Your resume will become a good bargaining tool! Your prospective employer will be interested and will stand up and take notice! This is exactly what you want.

Be bold about your assertive statements, but not too bold. Leave them wanting more. Tease a bit with nuggets of enticing information and leave them wanting more.

State a Clear Career Objective

After starting your resume with your contact information, your next section will clearly state your Career Objective. Once your prospective employer can see that what you bring to the table is what they want, they will continue to scan for more.

Be very clear in defining the name of the job or job title you are so qualified for. Be specific. Avoid general terms such as: I am seeking an engineering position. Well, OK, but what kind of engineering position are you looking for? Marketers signal in on one product at a time and so will you! Importantly, an electronic search, which is how most resumes are scanned today, will use specific position titles to find you.

You will hit the bull’s eye when you define your precise career direction, capture the right title, and put it down on paper. When prospective employers read your resume, they should have no doubt that you are seeking the exact job that they need filled.

Employers separate the wheat from the chaff very quickly. They look for career objectives that meet with their own expectations. They know there are many prospects out there who really do not have what they want.

Employers are not looking for close matches. Your Career Objective will convey that you will make the kind of contributions to the company that they need and want.

Keep in mind, too, that an employer is looking for a candidate who will meet their own needs, and not one who is looking to meet his or her own goals and agenda.

Your goal can be to offer this company your unique skill set and experience, but, the key is putting that across in a way that proves you are there to service them and not the other way around.

Your resume must grab them within the first few seconds, so, your Career Objective must be dynamite! Clearly state the job title you are going for and then add a few key phrases to show you have the skills to meet their exact needs…more on this later.

Develop a Professional Summary

The Professional Summary needs to pack a punch to be effective. It highlights the key credentials and experience that show how and why you qualify for the job.

You want the employer to focus in quickly on this section because it showcases your most important accomplishments, talents, and qualities.

After reading your Professional Summary, the employer should know, without any doubt, that you are the best man or woman for the job. This is where you will shine! This will be your moment to show your stuff. After being impressed by your summary, the employer will be compelled to read more!

In writing this section, you will not only use colorful and descriptive words but those that provide qualitative and quantitative evidence of your abilities. For instant, if one of your best talents is rig safety, write that you are one of the best safety men on the rig who greatly improve rig safety culture. Additionally, if there is any statistics support, you should add it into your resume because it will make you look so professional for the job.

The Professional Summary only contains information about you that is commendable and will set you apart from the crowd. Using the right kind of descriptive and complimentary words, especially if they contain quantitative information, you can easily achieve this. Your summary will show your prospective employer that you alone are the best fit for the position needed to be filled.

Tailor Your Professional Summary to Your Prospective Employer’s Needs

Before writing your resume, you wrote notes on what makes you the best candidate for your intended position. You will have looked at the many characteristics and qualities that you believe your prospective employer will be looking for in the ideal candidate.

Now is the time to tailor your professional resume summary to match those specific needs. Every statement made in your resume summary will be targeted to show the employer that you have what it takes to fill that position.
Work on writing positive and affirming statements that exemplify your unique abilities and talents and convey that you will be highly effective in the intended position. Practice using descriptive words. Use quantitative data – show rank, order, and volume, and qualitative data – show the type and breadth of your experience.

If you want to write that you are a good leader, write instead that you are a “proven leader” with initiative and motivational skills that cause others to act! Describe why you are good at what you do and leave no room for interpretation.

Words like “good” and “competent” are general terms. Expressions of success such as top revenue generator, most awarded by customers, and thrice promoted impel a hiring manager to take action on your resume. Describe how you excel and you will have done your job well!

Below, you will find a variety of suggestions for composing a professional resume summary. You can select those that best suit your skill-set. Experiment a bit, first, and then zero in on those that best reflect what you have to offer a prospective employer. Remember, your resume summary is critical to your resume’s success.

Few people will use all of the suggestions. Doing so might be seen as overkill. You are encouraged to say the most, while writing the least.

• Start with a concise phrase that describes your profession.
• Next, another concise phrase showing your broad or specialized experience.
• Make a few more concise statements to show the following:
  – the full extent of your skill-set
  – the variety of your skills
  – diversity in your experience
  – an accomplishment worth noting
  – anything remarkable about your accomplishments.

Optional

• Professional achievements
• Personal characteristics worth noting
• Concise statement to highlight professional objectives

Promote Your Skills and Accomplishments

In the summary section of your resume, you can brag a little. In the Skills and Accomplishments section you can brag a little more.

Citing your job Skills and Accomplishments will cap off all that qualifies you for your intended position. You will show your prospective employer that there can be no better person for this job and the journey stops with YOU!

How do you do this best? You continue to show that you are the right one for the job by going into more detail about all that you wrote of in your resume summary. This requires careful wording so as not to be repetitious. If you can pull this off in a professional manner, using words that glow, you will have the attention you are looking for!

The key point about writing about job Skills and Accomplishments is to remember you are not going to inform. You are going to highlight in more detail what your prospective employer already believes to be true about you as an ideal candidate.

Writing About Job Skills and Accomplishments

This is your opportunity to distinguish yourself from other job candidates. To do so, you should:

• Present any benchmarks or accomplishments achieved as a result of your unique skill-set.
• Use facts, figures, and statistics to show how your best efforts showed the best results.
• Highlight your specific talents and unique gifts as they relate to your job.
• Provide any and all accomplishments that set you apart.

To be the most effective, you will use clear, crisp writing that sums up. You are going into detail here, but not so much that this section reads like a story.

Key Point – Write so that you give hints and not complete details. You want your prospective employer to call you in for the interview to learn more! This is critical.

Present Your Professional Experience

You can use a number of headings here: “Professional Experience,” or “Professional History”; they both work well. Shy away from using “Work History,” or just “Employment.” These are not as effective and they do not look as professional.

To focus your reader, list all jobs held in reverse chronological order. Concentrate on giving good detail about your most current positions and offer only limited information about the jobs held earlier on. In many cases, you can write a simple statement to sum up holding several jobs earlier on.

Decide which you want to highlight more, your job titles or the names of the companies you worked for. The one you wish to highlight is listed first and then the next follows.

Example:

Shell Exploration and Production, Ltd. – Drilling Engineer

OR

Drilling Engineer – Shell Exploration and Production, Ltd.

For this section include all service work and internships as well as any key volunteer experience. Professional Experience is not only for paid experience.

List Your Education

As with your Professional Experience section, list your Education credentials in reverse chronological order. Show your completed degrees or licenses first, and then present your completed certificates and key training. Follow by listing Education in progress with a proposed date of completion.

Bold type anything you wish to highlight, such as your completed degrees. No need for too much detail here. Be concise by showing only your majors as well as any awards and distinctions received.

To be impressive, list grade point averages of 3.5 or better and highlight any courses of study engaged in currently as they relate directly to the position you seek.

If your awards and commendations are impressive, give them a section of their own. Always quote sources to substantiate your qualifications.

Sell Your Professional Affiliations

Under Professional Affiliations, show your community involvement and highlight current participation, especially in an area that might impress the employer as being relevant to key work issues. Give detail to show your abilities within specific areas, such as: “Initiated leadership role in the drilling organization bring the business unit to the next level”.

Hold back when stating political involvement as this may be judged negatively by an employer or company.

Impress With Publications

If you can offer a list of Publications, your employer will be impressed! Only highlight published material and summarize any credits you may have. Include stellar critiques and comments of your work and include only the most impressive.

The example of publication likes this:

“Experimental of cutting dryer in oil based mud to improve the mud recovery process in Gulf of Mexico SPE No 234567 – James Robert, BP”

Connect Through Personal Interests

This can be a tricky call for someone who does not have a lot of job hunting experience.

Do you or do you not write a Personal Interests section?

In most cases, you DO NOT unless your personal interests are related to the job position.

Those with targeted personal interests and skills that relate directly to the job sought can take advantage of Personal Interests to highlight how their hobbies and interests relate to the position they seek.

For example, a geologist who is applying for a chef geologist position might present a prospective employer with a recently published geologist journal. This showcases talent, creativity, and ability! An employer would like to see this!

On the other hand, a production engineer seeking a reservoir technical advisor position within a large oil corporation would not be smart to include a personal interests section to highlight his interest in collecting 18th century currency from India.

This becomes a judgment call on your part! In most cases, candidates opt to forgo this section.

Supply a List of References

The final closing statement of your resume can read, “References on Request,” or “References Available Upon Request.”

Some candidates do not use this as a close, however, and the prospective employer generally will assume you have references to offer. An employer will not hesitate to ask for references when needed, and they most always are.

Consider writing a separate page listing a few really good references. Include contact information, as well. If you can hand this page to your prospective employer when asked, you will appear organized, so it is always good to have references on hand.

Thanks for reading this article. In the next article, there are 3 resume styles that you can adapt for your one.

The post How To Create A Resume That Oilfield Employer Cannot Resist (Oilfield Resume Ep2) appeared first on Drilling Formulas and Drilling Calculations.

The following section of this article is devoted to a variety of different resume styles and formats.  This will give you full creative license to select what suits you best.  Getting the basics down first, though, is every bit as important as the final product you will create using these tips.

The more creative you are in writing about yourself, your credentials, your experience and everything else of importance to a prospective employer, the more attractive your resume will be to a hiring manager.

The three basic resume styles are:

1. Chronological Resume
2. Functional Resume
3. Chronological/Functional combined Resume

 The following sections below will give you more details regarding each resume styles and the example of resume.

Chronological Resume

The Chronological resume is the more structurally formatted of the three.

• Experience section is the key.
• Jobs are listed in detail.
• No focus on skills or achievements at the beginning of the
• Used generally when remaining in same job or career.
• Caters to conservative-type positions.
• Always has a Career Objective section and Summary section.
• Used especially with legal and academic professions.

This resume type is ideal when:

• Applying for positions within a more conservative profession.
• The job candidate is older, and more traditional.
• You are wanting to show good job detail and highlight employer names.

This resume type is NOT ideal when:

• You want to showcase your best qualities and experience.
• You are wanting to make a change in career.

Example of a Chronological Resume

Jason Coleman

1032 Sherwood Street, Wildwood, NJ 07886

201-555-9384

Jason.Coleman@gmail.com

Career Objective: Looking for consulting drilling superintendent for ultra-deep water in Gulf of Mexico.

Areas of Expertise:

• Highly deviated and horizontal well drilling
• High Pressure High Temperature (HTHP) well drilling
• Underbalance drilling
• Land drilling operation
• Offshore rig experiences: Jack up rig, semi-sub rig, drill ship
• Rotary steerable drilling tool
• Drilling operation management
• Water based and oil based mud
• Basic formation evaluation and geology for drilling
• Well testing operation on the drilling site
• Well control experience: driller’s method, weight and weight, volumetric, lubricate and bleed, dynamic kill
• Well control equipment: BOP both surface and subsea stack
• Safety and regulation compliance

Professional Experience:

2005 – Present: ABC Company, Houston, TX, USA

Drilling Supervisor Consultant

Managed deep water drilling operation in Nigeria and Angola which had cost approximately 600,000 us dollar a day expense. Provided operational suggestion to clients to improve rig safety and drilling performance. Trained young drilling engineers and drilling representatives to get more understanding regarding deep water drilling operations.

Achievement

• Successfully drilled and completed the complex subsea well head over 4,000 ft of water without any down time and injury.
• All the drilling projects were10 to 30 percentages under the planned AFE.
• No LTA while I was working on the drilling site.
• Over 2 million dollars save on an exploration well, Tata-01 Exploration, by utilizing new rotary steerable tool.

2000 – 2005: Robert Drilling Consultant, Saudi Arabia

Drilling Representative

Managed land drilling operations in Saudi Arabia. Ensure all personnel involving in the drilling operation follow safe work practices and procedures. Supervised drilling contractors and service companies to obtain the efficient drilling operation. Experienced with underbalance drilling operation on a land drilling.

Achievement

• Successfully drill multilateral wells penetrating over 1,000 meters of reservoir for each well.
• Successfully and safely kill several wells because of high pressure gas kick which had 3,500 psi initial surface casing pressure.
• Assist the production team to improve the productivity from underbalance drilling technique.
• No LTA while I was working on the drilling site.

1993 – 2000: American Exploration and Production, Houston, TX, USA

Senior Drilling Engineer

Took care of engineering sides as well design, drill string selection, completion design, drilling fluids, etc. Implemented performance metric for operation improvement. Brought new technology to drill complex wells in offshore The Gulf of Mexico as rotary steerable, casing drilling, HTHP oil based drilling fluid. Improved drilling waste management.

Achievement

• Drilled 5 high complex wells with the rotary steerable tool and all wells produced all together over 20,000 bpd in 1998.
• Improved well design strategy and reduced 2 unnecessary casing string from the previous casing design.
• Reduce over 1 million dollar of casing cost in 1998 by adapting the new well design

1982 – 1993: American Exploration and Production, Houston, TX, USA

 Drilling Engineer

 Supported a drilling engineering team and took care of several service contracts. Integrated offset well information into performance improvement plan. Worked with drilling supervisors at the rig site to improve safety and effectiveness of drilling operation. Implemented drilling best practices from the existing wells in the field. Created PDC bit selection criteria for the company.

Achievement

• Improved drilling performance in J-field (brown field)
• Applied new PDC technology to drill in offshore environment
• Drilled 5 vertical wells and 4 high deviated wells in J-field

Education:

• Master of Science in Petroleum Engineering, Texas at Austin, 1990
• Bachelor of Engineering in Petroleum Engineering, Texas at Austin, 1982

References: References available upon request.

Functional Resume

The next basic resume format is the Functional

• Showcases achievements and major skills from the top.
• Clearly states your strong suits.
• Employer does not need to read through boring job details.
• States (through summary) all you will bring to the table.
• Only brief mention of company names and positions held.

Highly recommended by resume writing professionals, this resume type is ideal when:

• Wishing to change careers, for those who job-jump; for homemakers returning to workplace; and for students and military professionals.
• Wanting to make only a minor change in job direction.
• Used as an effective aid in achieving a new direction or goal.

This resume type is NOT ideal when:

• Read by a more conservative employer looking for more information on each of your jobs.

Example of a Functional Resume

Jason Coleman

1032 Sherwood Street, Wildwood, NJ 07886

201-555-9384

Jason.Coleman@gmail.com

Career Objective: Looking for consulting drilling superintendent for ultra-deep water in Gulf of Mexico.

Areas of Expertise:

• Highly deviated and horizontal well drilling
• High Pressure High Temperature (HTHP) well drilling
• Underbalance drilling
• Land drilling operation
• Offshore rig experiences: Jack up rig, semi-sub rig, drill ship
• Rotary steerable drilling tool
• Drilling operation management
• Water based and oil based mud
• Basic formation evaluation and geology for drilling
• Well testing operation on the drilling site
• Well control experience: driller’s method, weight and weight, volumetric, lubricate and bleed, dynamic kill
• Well control equipment: BOP both surface and subsea stack
• Safety and regulation compliance

Drilling Supervisor Consultant

• Managed deep water drilling operation in Nigeria and Angola which had cost approximately 600,000 us dollar a day expense.
• Provided operational suggestion to clients to improve rig safety and drilling performance.
• Trained young drilling engineers and drilling representatives to get more understanding regarding deep water drilling operations.

Drilling Representative

• Managed land drilling operations in Saudi Arabia.
• Ensure all personnel involving in the drilling operation follow safe work practices and procedures.
• Supervised drilling contractors and service companies to obtain the efficient drilling operation.
• Experienced with underbalance drilling operation on a land drilling.

Senior Drilling Engineer

• Took care of engineering sides as well design, drill string selection, completion design, drilling fluids, etc.
• Implemented performance metric for operation improvement.
• Brought new technology to drill complex wells in offshore The Gulf of Mexico as rotary steerable, casing drilling, HTHP oil based drilling fluid.
• Improved drilling waste management strategy.

Drilling Engineer

• Supported a drilling engineering team and took care of several service contracts. Integrated offset well information into performance improvement plan.
• Worked with drilling supervisors at the rig site to improve safety and effectiveness of drilling operation.
• Implemented drilling best practices from the existing wells in the field.
• Created PDC bit selection criteria for the company.

Work Experience:

• 2005 – Present: ABC Company, Houston, TX, USA
• 2000 – 2005: Robert Drilling Consultant, Saudi Arabia
• 1993 – 2000: American Exploration and Production, Houston, TX, USA
• 1982 – 1993: American Exploration and Production, Houston, TX, USA

Education:

• Master of Science in Petroleum Engineering, Texas at Austin, 1990
• Bachelor of Engineering in Petroleum Engineering, Texas at Austin, 1982

References: References available upon request.

Combined Resume

The final basic resume format is the Chronological/Functional combined

• Can include headings of various jobs held with description of accomplishments.

OR

• Only a brief job description chronology.
• Only a brief Achievements and Skills section.

OR

• More detailed Summary that includes skills and qualifications.

This resume type is ideal when:

• Wishing to take advantage of both resume types.
• Wanting to highlight positives and downplay any possible negatives of either type of resume.

This resume type is NOT ideal when:

• Wishing to present a shorter resume

Example of a Combined Resume

Jason Coleman

1032 Sherwood Street, Wildwood, NJ 07886

201-555-9384

Jason.Coleman@gmail.com

Career Objective: Looking for consulting drilling superintendent for ultra-deep water in Gulf of Mexico.

Professional Experience:

2005 – Present: ABC Company, Houston, TX, USA

Drilling Supervisor Consultant

Managed deep water drilling operation in Nigeria and Angola which had cost approximately 600,000 us dollar a day expense. Provided operational suggestion to clients to improve rig safety and drilling performance. Trained young drilling engineers and drilling representatives to get more understanding regarding deep water drilling operations.

Achievement

• Successfully drilled and completed the complex subsea well head over 4,000 ft of water without any down time and injury.
• All the drilling projects were10 to 30 percentages under the planned AFE.
• No LTA while I was working on the drilling site.
• Over 2 million dollars save on an exploration well, Tata-01 Exploration, by utilizing new rotary steerable tool.

Technical Skills

• Drilling operation management
• Deep water drilling
• Well control for subsea stack
• High Pressure High Temperature (HTHP) well drilling
• Well testing
• Rotary steerable drilling tool
• Drilling fluids

2000 – 2005: Robert Drilling Consultant, Saudi Arabia

Drilling Representative

Managed land drilling operations in Saudi Arabia. Ensure all personnel involving in the drilling operation follow safe work practices and procedures. Supervised drilling contractors and service companies to obtain the efficient drilling operation. Experienced with underbalance drilling operation on a land drilling.

Achievement

• Successfully drill multilateral wells penetrating over 1,000 meters of reservoir for each well.
• Successfully and safely kill several wells because of high pressure gas kick which had 3,500 psi initial surface casing pressure.
• Assist the production team to improve the productivity from underbalance drilling technique.
• No LTA while I was working on the drilling site.

Technical Skills

• Drilling operation management
• Land drilling
• High Pressure High Temperature (HTHP) well drilling
• Rotary steerable drilling tool
• Drilling fluids
• Under balanced drilling
• Well control surface stack

1993 – 2000: American Exploration and Production, Houston, TX, USA

Senior Drilling Engineer

Took care of engineering sides as well design, drill string selection, completion design, drilling fluids, etc. Implemented performance metric for operation improvement. Brought new technology to drill complex wells in offshore The Gulf of Mexico as rotary steerable, casing drilling, HTHP oil based drilling fluid. Improved drilling waste management.

Achievement

• Drilled 5 high complex wells with the rotary steerable tool and all wells produced all together over 20,000 bpd in 1998.
• Improved well design strategy and reduced 2 unnecessary casing string from the previous casing design.
• Reduce over 1 million dollar of casing cost in 1998 by adapting the new well design

Technical Skills

• Drilling operation management
• Offshore drilling – Jack up rig
• High Pressure High Temperature (HTHP) well drilling
• Rotary steerable drilling tool
• Casing design
• Drilling fluids

1982 – 1993: American Exploration and Production, Houston, TX, USA

Drilling Engineer

Supported a drilling engineering team and took care of several service contracts. Integrated offset well information into performance improvement plan. Worked with drilling supervisors at the rig site to improve safety and effectiveness of drilling operation. Implemented drilling best practices from the existing wells in the field. Created PDC bit selection criteria for the company.

Achievement

• Improved drilling performance in J-field (brown field)
• Applied new PDC technology to drill in offshore environment
• Drilled 5 vertical wells and 4 high deviated wells in J-field

Technical Skills

• Contractor management
• Data workflow for drilling
• Bit selection
• Basic well design
• Drilling fluids

Education:

• Master of Science in Petroleum Engineering, Texas at Austin, 1990
• Bachelor of Engineering in Petroleum Engineering, Texas at Austin, 1982

References: References available upon request.

Finally, we wish these resume style examples will give you more ideas that you can use for your own resume. See you in the next chapter soon. 

The post Resume Styles – A Work of Art (Oilfield Resume Ep3) appeared first on Drilling Formulas and Drilling Calculations.

Writing the resume for newly graduated student is quite different from the experienced personnel because they don’t have working experience to add in the resume. This is not the problem because this section is dedicated for someone who just graduates from the collage.

You may start with your personnel information as address, telephone number, email, etc. Then you need to add the objective why you are applying for this position. Your objective should be precise because many people write so long objective but employers don’t understand what the new students want.

Next is the middle part of your resume which should be easy to read. The middle description should include your educational background, your experiences when you are in the school, your technical knowledge, your computer skill, etc. The most important of this section is your educational background.  When you mention your education, you need to start with your recent degree including your degree with date, university name and the grade.

Additionally, if you have an internship experience, this information should be included in your resume too because many employers will seek the people who has the same experience for the position. You should mention the joining date of the position that you are working for and the company name.

Example of Newly Graduated Student Resume Applying For Reservoir Engineering Position

Joe Simon

44-46 Morningside Road

Edinburgh

Scotland

EH10 4BF

Joe.Simon@gmail.com

Objective: Seeking for the appropriate position of reservoir engineer.

Education:

Heriot-Watt University, UK – June 2010
Honors degree in Petroleum Engineering. GPA 3.70

Irvine High School, Canada – June 2006
Graduated with high honors in mathematics and science.

Professional Experience:

 British Petroleum (BP), UK – Summer 2009

Assisted senior reservoir engineers to determine the optimum oil recovery in the BP05 reservoir. Designed gas lift for two wells using Nodal Analysis. Studied in rock properly of deep deposition carbonate rock to determine the potential of drilling into deep reservoir (>4,000 meters from the seabed).

Chevron, UK – Summer 2008

Performed pressure transient analysis to determine reservoir properties as wellbore skin, shape of reservoir, etc. Researched the feasibility of converting the normal wells into gas lift wells.

Extra Curricular Activities

• A member of SPE student chapter in UK
• Organized photography club for two years

 Skills

 Computer: Microsoft Office (word, excel, access, powerpoint), Reservoir engineering tool kits, KAPPA – Pressure transient analysis, Merak VOLTS reserves.

Language: English, Spanish and French

The post Writing Resume For Newly Graduated Students For Oilfield Job (Oilfield Resume Ep4) appeared first on Drilling Formulas and Drilling Calculations.

A degasser is equipment used to remove entrained gas in drilling fluid so it prevent or minimize reduction of hydrostatic pressure due to gas cut mud. When drilling mud passing over the shale shakers while drilling, gas will normally be released. However, the wellbore could receive additional volumes of gas and these need to be removed from the mud. If not removed from the circulating system properly, recirculation of mud containing gas will reduce the well’s hydrostatic head. With a degasser, this can eliminate or minimize loss of hydrostatic pressure.

Figure 1 – Degasser (Courtesy of NOV)

Mounted over the active pit, degassers are essentially a one-stage liquid/gas separator. With a maximum lift to the inlet of around ten feet, mud vacates the submerged pipework in the mud pit and enters the degasser. From here, a three hp electric motor will power a vacuum pump and this should be mounted atop the degasser itself. By the pump, the vacuum is then applied to the vapor space.

Ultimately, the range applied by the vacuum will depend on the density of the mud passing through. In most cases, it will offer between 2-5 pounds per square inch (between 8 and 15 inches of mercury). In terms of extracting gas from mud flows, 900 gallons per minute is likely to be the maximum rate.

Figure 2- Degasser Diagram

Sometimes, the mud’s separator won’t be able to remove extra small gas bubbles in the drilling fluid due to their size. Therefore, a degasser can remove these bubbles; depending on the project, a certain degree of vacuum can assist with removing entrained gas. In order to reduce the risk of gas entering the pit after breaking out of the drilling fluid, the drilling fluid discharge line from the mud/gas separator and the drilling fluid inlet line to the degasser should be within close proximity to one another.

Additionally, degassing for all drilling fluid can be ensured by increasing the drilling fluid throughput capacity beyond the maximum flow rate from the well. After entering the top of the degasser, there’s a pipe closed in at the far end through which the mud needs to flow; to form an open trough, the pipe’s top is cut away horizontally. Over inclined plates, the mud should spill over the trough and this allows the gas to be released as the mud spreads over a large surface area. In the vapor space, the vacuum plays an important role too as the mud carries over the plates as evenly as possible. Once this process has occurred, the gas can either be burned away from the rig or vented through a vent line from the tank.

What happens to the mud now free from gas?  Well, it now has a normal weight and is allowed to fall to the bottom of the degasser’s cylinder. Before entering the mud stream, it travels through a 5/8th-inch extractor jet. After passing through, there’s no danger of the mud being at a higher pressure than the vacuum pressure.

Mud can then be sent to the active pit, but not before the safety valves jump into action. If the working pressure reduces, these valves stop the mud from coming into contact with the vacuum pump and therefore being sent back up the degasser.

References  Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post What is a Degasser on a drilling rig? appeared first on Drilling Formulas and Drilling Calculations.

Poor Boy Degasser or Mud Gas Seperator, located downstream of the choke manifold, is a vertical vessel used to separate any gas from drilling fluid during well control situation. Once the gas has been separated, it can pass through the vent line in the derrick. Alternatively, as long as it’s a safe distance from the rig, it could even be vented.

Figure 1 – Poor Boy Degasser (Courtesy of H-Screening)

With mud’s separators, there are two main types. Also known as a ‘poor-boy’ and a ‘gas buster’, the more common of the two is called an atmospheric mud/gas separator. However, some mud/gas separators are designed to operate at moderate back pressure. Although these will mostly operate under 100 psig, it’s possible to come across those that work at the atmospheric gas vent line pressure plus the vent line friction drop. The simple diagram of poor boy degasser is show in figure 2.

Figure 2 – Poor Boy Degasser (Mud Gas Separator) Diagram

As long as they have a liquid level control, all separators can be referred to as pressurized mud/gas separators. Ultimately, there are benefits and drawbacks to both pressurized and atmospheric mud/gas separators. Despite the differences, both types also have some common requirements. For example, the capacity of the separator may sometimes be exceeded, or a malfunction may be experienced. With this in mind, both must have a by-pass line to the flare stack as a precaution.

When the drilling fluid impinges on the vessel’s wall, certain precautions should also be taken to prevent erosion. In case of plugging, easy cleanup should be possible with lines and vessels and these are more provisions to consider. For well testing operations, the rig mud/gas separator isn’t recommended for use unless it has been specifically designed for use in these conditions.

When a kick is being displaced, the mud/gas separator should be lined up constantly. As well as removing large gas bubbles from mud, the separator is also used to cope with gas flows as the influx reaches the surface.

Often, there are questions regarding the volume of gas with which each separator can safely cope. There will be a limit, and there’s a danger of gas getting into the shaker header box if this limit is breached. When it comes to calculating a maximum gas flow rate for each separator, an estimate can be made.

What factors will limit this flow rate?

Mainly, this will come from the relationship between the hydrostatic head of fluid located at the mud outlet and the back pressure at the outlet to the vent line. At times, there’s a risk the back pressure at the gas flow will be greater than (or even equal to) the mud outlet’s available hydrostatic head. When this occurs, the shaker head tank may be in danger.

At all times, minimizing risk should be a key objective and this can be aided with a large ID and straight vent line. Elsewhere, the mud outlet should be set up with a hydrostatic head of at least ten feet.

Furthermore, it’s important to keep an eye on the pressure gauge used for back pressure. If registered readings are showing pressure close to the discharge line’s hydrostatic head, this is a warning of a so-called ‘blow-through’. When large amounts of condensate or oil are displaced to the surface, the maximum hydrostatic head may not be equal to that of mud.

When the separator is in danger of breaching the safe operating limit, check that the well isn’t over-pressured and close in the choke. Alternatively, switch the flow to the burn pit or overboard line.

References

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

Separation, H. (2019). Mud Gas Separator, Poor Boy Degasser | H-Screening. [online] H-Screening. Available at: https://www.h-screening.com/poorboy-degasser/ [Accessed 31 Mar. 2019].

The post What’s a Poor Boy Degasser (Mud Gas Separator)? appeared first on Drilling Formulas and Drilling Calculations.

Now that we have covered the most basic elements of an impressive resume from previous articles, let’s take a look at some finer resume formatting points. This section will describe about general guidelines for oilfield resume formatting and designing a compelling resume that suits for yourself.

Your resume should be written to look appealing to the eye. This is best accomplished by keeping in mind the following:

• Structure looks clean and flows well
• Very easy to read/not at all complicated
• Easily understood with simple wording and phrases
• Contains good overall balance
• Not crowded/contains plenty of white space
• Sections are concise and shorter when possible

All formatting should be consistent. And not too heavy on the bolding, italics and underlining. These features should only be used for best effect and not in uniformity.

Your resume will be your front line in communication. Before you meet your prospective employer, your employer will meet you via your resume. If there are mistakes in your resume, the employer will expect the same lack of attention to detail in your job. Your resume should be error free. This means free of typos, improper spelling, poor grammar, improper punctuation, and errors in fact.
To recap, the key information in your resume should include:

• Name
• Address
• Phone
• Email
• Career objective
• Technical expertise
• Positions held list
• Reverse chronological order
• Education credentials
• Degrees attained
• Targeted information as necessary

The positions held list will include:

• Position title
• Name of company
• City and state of company
• Years there
• Earlier held positions can be summarized
• Part-time work can be excluded

Designing a Compelling Resume

Create a work of art! Use the best supplies for your resume:

• A laser printer or an ink jet printer to produce the best results
• A good-sized typeface (font) in 11 or 12 point.
• Off-white, ivory or bright white Letter or A4 paper, in high quality.

Submit a resume without smudges or staples, and leave a generous border.

A Long Versus Short Resume

A shorter resume is often best, however, if what you need to write takes up 3 pages, then offer 3 pages. There is no hard-and-fast rule for resume length. Just make certain you do not bore them with the details. Always leave them wanting to know more. Remember, you are marketing yourself and not your entire life history.

Add good variety. Break it down into sections. Your resume will contain no more than six lines of writing in any one writing section or paragraph (summary, skills section, accomplishment statement, job description, etc.) If you require more, start a new section or a new paragraph.

Ensure the Resume is Easy to Follow

You need to start each section with your most important information on the first line. This will be read the most. Additionally, you should use bold caps to highlight key sections and information. Your name, section headings, skill headings, titles or companies, degrees, and school name can all be written in boldface. Your name should be on the top of each page of your resume.

Ensure parallel content elements use the same design format

Omit any kind of information that can be seen as being controversial, such as political affiliations.

Make Contact Information Easy to Find

Submit an accurate telephone number with area code. Be sure the phone number on the resume will be answered in-person or by an answering machine, Monday through Friday, from 8-5 pm. You want to be available when invited in for that important interview.

If you do not have an answering machine, buy one. Include your e-mail and fax numbers as an alternate means of reaching you.

Put Your Best Foot Forward

The job of the employer is to pour through sometimes hundreds of resumes each and every day. They have a well-trained eye for scanning and identifying the candidates that interest them most. All the same time, they must read through all kinds of really boring information.

Some resumes read like a long list of data that is anything like remarkable. Your resume, however, will not. Your resume will be formatted to give your prospective employer your most meaningful and interesting information first and then all of the pertinent, less exciting information, after.

Your resume packs a punch to begin with and then you boldly assert your best qualities and talents. Now, you will back up your assertions by proving you know your stuff. You will now show how qualified you are for the job based on your work experience.

We hope that you enjoy reading this section. Additionally, we will share more oilfield resume related articles so please follow us

The post General Resume Formatting Guidelines for Oilfield People appeared first on Drilling Formulas and Drilling Calculations.

In the previous article, Common Problems and Complications During Well Kill Operation, it is about commons complications that can be possibly seen while performing well control operation. For this article, it will discuss other wellbore problems which are stuck pipe, surface pressure reaching to MAASP, lost of control and hydrate.

Stuck Pipe

During a well control operation, a stuck pipe can occur and this has the potential to lead to serious issues. Whenever the pipe is off bottom, the chances of the pipe getting stuck increases. Therefore, rotating the pipe should reduce the risk of this problem occurring. However, with the well shut it, it is impossible to rotate to minimize stuck pipe so the stuck pipe should be dealt after the well is properly secured.

Throughout well control operation, wellbore pressures will be high and this means the most common cause of a stuck pipe comes from differential sticking. However, this isn’t to say mechanical sticking can’t occur if the hole sloughs and packs-off after coming into contact with the influx fluids.

Operation can normally continue when the pipe is differentially stuck (with the bit on bottom) because the well can still be killed with circulation. Once the well is killed, then the pipe can be free safely later.

When the bit is off bottom and the pipe becomes differentially stuck, this is a more complicated scenario since it’s more difficult to reduce wellbore pressure; at that depth, it’s normally impossible to achieve a reduction by circulation. Although there may be opportunities to spot a freeing agent and free the pipe, volumetric control is the chosen method if the influx was swabbed in.

When the pipe is mechanically stuck, the pipe can be freed by spotting a freeing agent and working the pipe (by combining the two, the desired result is achievable!).

Figure 1 – Stuck Pipe due to Differential Sticking

Surface Pressure Approach to the Maximum Allowable Annular Surface Pressure (MAASP)

Maximum Allowable Annular Surface Pressure (MAASP) is the maximum annular pressure which will cause formation break down. MAASP can be in a static condition and a dynamic condition (circulating).

At the static condition, MAASP’s equation is listed below;

MAASP, psi = (Leak Off Test pressure, ppg – current mud weight, ppg) x 0.052 x Casing shoe TVD, ft

At the dynamic condition, due to friction pressure in the annulus while circulating, it is very difficult to calculate an accurate MAASP therefore it is not recommended to determine the dynamic MAASP while circulating the kick out of the well. Furthermore, you should NOT use MASSP at the static condition while circulating. For example, you determine the static MAASP of 1,000 psi and while circulating, casing pressure can go more than 1000 psi. If you try to lower the casing pressure down by misleading the interpretation of this value, the additional kick will go into the well and finally it will make the well control situation even worse.

During a well control operation, MAASP no longer needs to be considered once the top of an influx is displaced (once it moves past and then above the openhole weak point). When surface pressures exceed MAASP, there are options if the downhole pressures are caused by a kick below the openhole weak point. For example, the bottomhole pressure can be maintained at, or slightly higher than, the kick zone pore pressure.

When the openhole weak point is over-pressured, there are many consequences to assess considering the following factors;

• Cement job’s quality
• Casing shoe’s depth
• The extent of the over-pressure in the openhole weak point
• Characteristics of the openhole weak point
• The period of time for which the openhole weak point will be over-pressured
• The risk of broaching around the casing
• All applicable safety factors in the MAASP calculation

When the formation is underbalanced, there are different consequences to assess considering the following factors;

• Kick zone’s permeability
• Type of kick zone fluid
• Period of time for which the kick zone will be underbalanced
• Degree of underbalance

Only once these factors have been considered can the appropriate course of action be chosen. This being said, underbalancing should only ever occur in a kick zone in exceptional circumstances; one example would be when the zone has low permeability. After shutting in a well that has kicked, the rate of pressure build can be used to assess the situation fully.

Loss of Control

When a loss of control is experienced during a well control operation, this is normally a result of exposed formations or excessive loading of pressure control equipment. However, some incidents in the past have noted equipment failure where pressures are significantly lower than rated values.

How can it be happened?

Lack of proper maintenance, corrosion, and faulty manufacture are common causes. When exposed to corrosive fluids, including H2S, high-pressure equipment is known to be more susceptible than most to failure.

Unfortunately, there aren’t necessarily specific procedures to follow when a loss of control is experienced. This being said, we must note that personnel safety should always be the priority when taking action.

Hydrates

In the past, many have compared natural gas hydrates to snow in terms of appearance. Containing chemical compounds of liquid water and light hydrocarbons, they normally form at certain conditions (pressure) when the temperature is higher than water’s freezing point. When high gas velocities are present, the formation process speeds up; this is also true with a downstream of a choke and at elbows (causing mixing in hydrocarbon components), pressure pulsations, and various other agitations.

Gas hydrates during well control operations can cause numerous issues, including;

• At and downstream of the restriction or choke, there could be a plugging of surface lines. When low pressure equipment, such as a gas vent line or poorboy separator, experience high gas flow rates, the danger increases somewhat. With these conditions present, the formation of hydrate plugs can quickly overpressure (well control equipment with low pressure).
• The wellbore annuli can be sealed and the drillstring immobilised when subsea choke/kill lines are plugged and therefore subsea BOPs are unable to be opened or closed. Previously, incidents have been recorded with subsea stacks at a depth of 1,150 feet (and more!).
•  Temperature, gas composition, liquid content, and pressure are the four main factors determining the potential for hydrate formation. Using Figure 2, the formation of hydrates can be predicted and the conditions for such an occurrence can include cold-water environments (at a subsea stack).

Figure 2 – Temperature at which Gas Hydrates will freeze (Katz)

Meanwhile, the temperature decrease associated with a pressure drop can be predicted using Figure 2. If we use a choke as an example, gas could be at 3,000psi and 90 degrees Fahrenheit. If this gas was choked to 1,800 psi, temperature decrease could be expected to reach 55 degrees Fahrenheit. Therefore, we can expect hydrate formation.

To fight against hydrates, the following techniques can be useful;

Antifreeze – Firstly, antifreeze agents can be injected into the gas flow and this includes methanol. By dissolving liquid water deposits, the idea is to reduce the temperature at which hydrates form. During well testing operations, methanol is commonly injected at the subsea test tree from a floating rig.

How is it achieved?

The choke manifold is considered the best place to inject methanol at the surface (as long as it’s injected upstream of the choke). Many Texstream chemical injection pumps that have a high pressure, are suited towards this particular application.

Heating – After antifreeze, gas well testing operations will normally have a steam exchanger. To prevent the formation of hydrates, this is seen as the most effective solution (as well as being reliable!). Rather than choosing one of these first two options alone, best results are seen when they’re combined.

Line Pressure – Finally, the hydrates can be melted when line pressure is reduced. Compared to the first two options, this one is very much a temporary measure and one that isn’t always practical. Unfortunately, a large chunk of time is required for the line to clear after hydrates have formed.

To deal with hydrates, adequate contingency needs to be provided along the above lines; this is particularly true when there’s a potential that a hydrate formation exists. In addition to this, subsea water pressures and temperatures should be monitored at the surface if a gas kick is experienced.

References

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

Crain, R. (2015). Crain’s Petrophysical Handbook – Permafrost And Gas Hydrates. [online] Spec2000.net. Available at: https://www.spec2000.net/17-gashydrate.htm [Accessed 10 Jul. 2019].

Coleman, S. (2014). Learn about Maximum Surface Pressure in Well Control (MASP, MISICP and MAASP). [online] Available at: http://www.drillingformulas.com/learn-about-maximum-surface-pressure-in-well-control-masp-misicp-and-maasp/ [Accessed 10 Jul. 2019].

Coleman, S. (2011). Stuck Pipe Summary. [online] Drillingformulas.com. Available at: http://www.drillingformulas.com/stuck-pipe-summary/ [Accessed 10 Jul. 2019].

YouTube. (2019). Hydrates on Deepwater BOP Stack. [online] Available at: https://www.youtube.com/watch?v=GjcJ3iR0IFU [Accessed 10 Jul. 2019].

The post Possible Wellbore Problems during Well Kill Operation appeared first on Drilling Formulas and Drilling Calculations.

There are few good resume writing tips that we would like to share.

Language used in your resume should be: 

• Easy to read and understand quickly
• Specific and to the point rather than general
• Active sentences rather than passive ones
• Written to express not impress
• Express yourself clearly and easily
• Fact-based and not put the fake information

DO’s and DON’Ts for Resumes

DO’s:

• Writing format should be consistent in format and content
• You should make your resume it easy to read and follow. Your resume has less than a minute to initially evaluate by the company.
• Spacing, underlining, italics, bold, and capitalization are recommended to use for emphasis the important subject.
• When you use list headings (such as job experiences), they should be in order of importance. Additionally, information list within the heading should be in reverse chronological order (most recent first)
• If you will send the electronic version of your resume in PDF format, you must ensure that your resume formatting is properly converted.

DON’Ts :

• Personal pronouns (such as I) should not be in the resume.
• A narrative writing style should not used.
• Use slang or colloquialisms will degrade your professional.
• Grammar and spelling errors in your resume make you look bad.
• Writing resume too long. You need to keep in mind that the oilfield employers need people who can express himself precisely.

The post Oilfield Resume Writing Tips appeared first on Drilling Formulas and Drilling Calculations.

This is the introduction to shallow gas well control which will briefly describe the overview of shallow gas and some related information. We have few articles regarding this topics and we will separate into small parts for better understanding. Let’s get started.

Whenever offshore shallow gas accumulations are seen, they’re normally linked with down sand lenses enveloped by mudstones. Typically, lenses will be permeable, unconsolidated, and highly-porous when found in shallow depths. Although normally flat, thin, and normally pressured, many have previously encountered over-pressured lenses. When at this depth, one cause of over pressure is inclination of the lens; this can therefore increase both the lens height and pore pressure gradient (top of the lens).

Although rare, shallow gas can also be linked with vuggy limestone or buried reefs; these have the risk of being infinitely permeable and incredibly porous.

Shallow gas kick

When drilling in the top-hole section, resulting kicks from shallow sands can be dangerous with short casing strings; there are many case histories to show this. Charged formations can also cause kicks from shallow sands and this itself can be a result of improper abandonments, previous underground blowouts, casing leaks, injection operations, and poor cement jobs.

The example of the shallow gas blow out is below.

Sedco 700 Shallow Gas Blow Out 6 June 2009

 When it comes to shallow gas kicks, the most common cause is a loss of hydrostatic head and this can be a result of two common problems;

• Expanding drilled gas unloading the annulus
• Poor hole fill while tripping
• Losses through the overloading of the annulus with cuttings

In order to minimize the risk of inducing a shallow gas flow, we recommend some general precautions including restricting the rate of penetration, drilling a pilot hole, drilling riserless, and always monitoring the hole.

High flow rates of gas are often produced by shallow gas flows; high quantities of rocks from the formation are also possible. This is particularly true after long sections of sand have been exposed. When a shallow gas flow occurs, the representative responsible should contact a senior contract representative; all non-essential individuals should be evacuated from the rig. This eventuality should always be addressed, and there should be an implementation of the contractor’s emergency evacuation.

A shallow seismic anomaly, referred to as a bright spot, should never be drilled through since this suggests shallow gas. If bright spots are seen in upcoming drilling locations, the best solution would be to avoid a hazard by moving the rig. If possible, the new drilling location should be located on a shallow seismic shot point.

Just because no bright spots exist, this doesn’t mean you can be certain of a lack of shallow gas. In addition to this, it’s also important to note that subsequent directional wells can still hold shallow gas even if one well in a series fails to offer any (drilled from a surface location). Therefore, care should always be taken when drilling from the same surface location.

For the next topic, we will discuss about riserless drilling on a floater and what we should prepare for it.

References

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

The post Introduction to Shallow Gas Well Control appeared first on Drilling Formulas and Drilling Calculations.

According to many company policies, unless circumstances and conditions apply, as stated in the Drilling Policy and Guidelines Manual, the surface hole should be drilled riserless. By doing this, it’s possible to eliminate the most common cause of blowouts in a shallow and pressured gas reservoir (most importantly, the loss of hydrostatic head). Of course, there will still be a risk of penetrating an overpressured reservoir so there must always be a contingency plan in place. Prior to stud, the operator and the drilling contractor must also together on the plan and it needs to include;

• Common procedure when winching the rig off location
• Common procedure when a shallow gas flow occurs

Normally, the pre-spud meeting will be the ideal time and place to discuss contingency plans. A 10-degree cone of low-density water is normally produced after a gas blowout in open water and there will also be a discharge of highly-flammable gas. The current and water depth will decide the intensity of the blowout with greater water depth leading to more dispersed water from the plume. When a current is active, the result would be a plume away from the rig.

West Vanguard Shallow Gas Blowout

A loss of buoyancy can occur for a floating vessel within a plume of expanding gas; this being said, when the water depth creates a negligible effect on a semi-submersible at operating draft, then this reduces somewhat. A vessel can be displaced after an eruption of gas, and a drillship can also keel towards the plume when constrained by its moorings; this would reduce its freeboard even further. When the conditions are calm, there’s always a risk of fire if the gas is trapped within a confined area. In these conditions, the gas disperses slowly.

All hazards can only be assessed, in terms of severity, at the time. In truth, the crew and vessel aren’t likely to be under excessive danger but there are still some precautions and considerations that must be considered. Before and during the surface hole being open, this includes;

• Securing all hatches and therefore preventing inflammable gas in the voids, or even downflooding when a loss of heel or buoyancy causes a reduction in the freeboard; this is very important for a drillship.
• Running a float valve in the drillstring.
• Monitoring all weather conditions and the current. Signs of gas should also be considered in the sea surface.
• Mooring the rig with enough moorings so the rig can be winched around 400ft from the plume itself. The chain stoppers should only be applied after setting the surface casting, and windlasses should remain on their brakes as long as it’s practical.
• Keeping enough mud on site so the hole volume can be filled twice over.
• Distributing the cuttings and drilled gas by limiting the ROP, drilling the pilot hole, and circulating at a high rate.
• Keeping personnel and facilities available at all times to heave in up current (not downwind), and slack off whatever moorings lie closest to the plume. Before anything takes place, a contingency plan should be created so every individual on the site knows their roles and responsibilities when dealing with potential issues.

Shallow Gas Flow – Whenever a shallow gas flow is detected, the priority should be to control the well. As long as there’s no danger to the rig or to personnel nearby, this can be done by pumping either seawater or mud at the maximum rate possible.

Immediate Danger? – If the rig or individuals are under immediate danger, the priority should be to shear the pipe or drop the drillstring. From here, the rig can be winched to safety (away from the gas plume!).

References

Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.

Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.

Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.

Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.

Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.

Members.home.nl. 2005. West Vanguard Blowout – Oil Rig Disasters – Offshore Drilling Accidents. [online] Available at: <http://members.home.nl/the_sims/rig/vanguard.htm> [Accessed 21 May 2020].

The post Shallow Hazard while Drilling Without a Riser (from a floating rig) and Encountering Gas appeared first on Drilling Formulas and Drilling Calculations.