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Torque and drag analysis
Predicting Thrust Loss of Ship Propellers Due to Ventilation and Out-of-Water Effect
Kozlowska, Anna M. (Norwegian University of Science and Technology / Rolls Royce University Technology Centre “Performance in a Seaway”) | Savio, Luca (Sintef Ocean) | Steen, Sverre (Norwegian University of Science and Technology / Rolls Royce University Technology Centre “Performance in a Seaway”)
This article presents a propeller ventilation model that is tuned on experiments performed in open water condition in a towing tank. The main purpose of performing the experiments was to obtain more data at higher advance numbers for validation purposes and to make a calculation model for thrust and torque loss due to free-surface proximity. Tests were performed at different draughts. For each draught, the propeller was tested at different propeller speeds n = 9, 12, 16, and, 16 Hz at advance number in the range from J = 0 to J = 1.0. The different advance numbers were obtained at different propeller speeds so that for the same advance number, different propeller thrust values were tested, so that the effect of propeller loading can be seen independently from the speed of advance J. The main focus of this article is to explain and validate a prediction model for thrust loss due to ventilation and out-of-water effect. 1. Introduction Ventilation is a phenomenon of air-drawing seen on structures operating below the free surface, such as hydrofoils, rudders, and propellers. Propeller ventilation is related to the propeller coming close to the free surface and "sucking" air into the propeller, or when the blades are piercing the free surface. In these cases, propeller ventilation leads to a sudden and large loss of propeller thrust and torque, which might lead to propeller racing and possibly damaging dynamic loads, as well as noise and vibration. Ventilation typically occurs when the propeller loading is high and the propeller submergence is limited, and when the relative motions at the propeller are large because of heavy seas. Propeller ventilation inception depends on different parameters, i.e., propeller loading, forward speed, and the distance from the propeller to the free surface, see e.g., Smogeli (2006); Koushan (2006a-c); Kozlowska et al. (2009); Califano (2011); Jermy and Ho (2008); Hough and Ordway (1965); and Kozlowska and Steen (2010).
- Reservoir Description and Dynamics (0.68)
- Well Drilling > Drillstring Design > Torque and drag analysis (0.34)
This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 184074, “Microdogleg Detection With Continuous Inclination Measurements and Advanced BHA Modeling,” by K.A. Mills, SPE, and S. Menand, SPE, DrillScan, and R. Suarez, SPE, Nabors, prepared for the 2016 SPE Eastern Regional Meeting, Canton, Ohio, USA, 13–15 September. The paper has not been peer reviewed. Microdoglegs are a natural effect of any vertical or directional well that can explain a wide variety of downhole problems. A trajectory-prediction model able to calculate the inclination and azimuth approximately every 12 in. has been developed to estimate microdoglegs using standard surveys, bottomhole-assembly (BHA) data, and steering parameters. This new methodology combining downhole data measurements with drillstring-modeling analysis highlights the potential for drilling optimization and wellbore placement. Wellbore Trajectory Standard Surveys. Surveys are generally taken at an interval of every 95 ft, the length of one stand. While the general recommendation is to decrease the survey interval when building faster than 3°/100 ft, this is often neglected because there is no advantage seen in wellbore-positioning-uncertainty models. The well path between each survey point typically is calculated using the minimum-curvature approach, which assumes a curve of equal angle along the surface of a sphere with only one radius in a 3D plane. Looking at the well as a whole, this approach appears logical and yields reasonable-looking trajectories; however, when examining more-frequent survey data, it becomes obvious how this method can mislead users to think that the well path is much smoother than it actually is. Continuous-survey measurements have enabled the industry to take a closer look at what is happening between survey points, in highlighting microdoglegs quite often undetected by standard surveys. Continuous Surveys. Doglegs are generally discussed on a well level. Wells are analyzed for tortuosity looking at the change in trajectory from one survey point to the next. Little thought is given to what changes happen between those points unless a dysfunction occurs. Aggressive directional work can lead to the creation of microdoglegs, or doglegs on a scale of a few feet. Quick changes in direction create microdoglegs, which can contribute overall to higher torque and drag. In examining continuous surveys, the actions of the directional driller can be seen clearly and doglegs can be examined more closely. While continuous-survey data have become more common in the industry, not all measurement-while-drilling (MWD) tools are equipped for the measurements and, generally, data must be processed at surface on the basis of the previous survey. In the absence of continuous-survey data, BHA modeling run on a step-by-step basis can aid in wellbore placement, failure analysis, and post-well evaluation.
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
Mitigating Drilling Vibrations in a Lateral Section Using a Real-Time Advisory System
Bailey, J. R. (ExxonMobil Development Co.) | Payette, G. S. (ExxonMobil Upstream Research Co.) | Prim, M. T. (Zakum Development Co.) | Molster, J.. (Zakum Development Co.) | Al Mheiri, A. W. (Zakum Development Co.) | McCormack, P. G. (Halliburton Energy Services) | LeRoy, K.. (Pason Systems Co.)
Abstract A real-time drilling data analysis and recommendation system that leverages surface drilling data was deployed in the lateral section of a well from an artificial island in Abu Dhabi. A key objective of this technology is to provide the driller with an easy-to-use display of a novel drilling performance map. This paper presents data from this demonstration run, illustrates the features of this technology, and provides general observations on optimization of drilling parameters in this hole section. The prototype advisory system demonstrated value by recommending rotary speed and ROP (Rate of Penetration) values to continuously optimize the tradeoff between stick-slip vibrations and MSE (Mechanical Specific Energy), depending on depth and formation being drilled. The system relieves the driller of tedious drilling test calculations and seeks to continuously optimize drilling performance. The optimization objective function (OBJ) includes MSE, ROP, and TSE (Torsional Severity Estimate) and provides a surface map that is stoplight color-coded to display the optimal drilling parameter values. TSE is calculated from a drillstring model and observations of the cycle-by-cycle swing in the surface torque. The typical drilling optimization paradigm holds that higher rotary speed can mitigate stick-slip vibrations at the expense of increased whirl vibrations, and higher WOB (Weight on Bit) tends to increase stick-slip and mitigate whirl. The operational challenge is that these tendencies can vary from run to run, and even within an individual section as pipe length, formation, bit condition, etc. all play a role in the balance between these dysfunctions. In this application, the system demonstrated that increased rotary speed could mitigate stick-slip for about the first 2,500 ft of the lateral section. From this point on, the drillstring was in full stick slip for all available drilling parameters. However, whirl was sensitive to the effective WOB, determined by the ROP control setpoint in this application. To stay within torque limits and provide sufficient WOB to control whirl, the advisory system actually recommended lower RPM. This application provided an opportunity to compare the calculated stick-slip levels with bit speed measured at a downhole sensor. Excellent agreement was found between measured stick-slip and the TSE determined from the drillstring model and surface torque throughout the 10 kft lateral. This field demonstration was a first application of the system in ROP control mode, providing new insights into drilling parameter tradeoffs. The system prioritizes objectives with high variability over those with lower variability to improve drilling performance. The data was initially unexpected and led to lower rotary speeds and increased WOB in spite of stick-slip, revealing that it was possible to control whirl without making stick-slip significantly worse.
- North America > United States > Texas (0.46)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.35)
- North America > United States > Texas > Permian Basin > Yeso Formation (0.99)
- North America > United States > Texas > Permian Basin > Yates Formation (0.99)
- North America > United States > Texas > Permian Basin > Wolfcamp Formation (0.99)
- (21 more...)
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drillstring Design > Drillstring dynamics (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
Optimal Matching of Bit and Reamer for Increased Reliability of Hole-Opening BHAs
Kueck, A.. (Baker Hughes, a GE company) | Ichaoui, M.. (Technische Universität Braunschweig) | Herbig, C.. (Baker Hughes, a GE company) | Hohl, A.. (Baker Hughes, a GE company) | Ostermeyer, G. P. (Technische Universität Braunschweig) | Reckmann, H.. (Baker Hughes, a GE company)
Abstract Mechanical loads in hole-opening BHAs result in tool failures and generate maintenance costs and non-productive time. This paper presents a method to increase the reliability of hole-opening BHAs by optimally matching the bit and reamer. The weight and torque distribution between the bit and reamer is predicted using a stationary load model. New quality load curves facilitate the evaluation of bit-reamer combinations in a user-friendly way. The model and the load curves are validated on a unique set of field data, enabling determination of the model's accuracy. The model is based on the mechanical specific energies at the bit and at the reamer. The model assumes the RPM and rate of penetration to be constant, the BHA is rigid in the axial and torsional directions and the lateral movement is blocked. Quality load curves are deduced that depict the load distribution in one plot. The model is validated on a unique data set that includes several high-precision measuring tools placed along the drill string. The unconfined compressive strength over depth that usually is not measured in other runs is available. The data set enables precise determination of the axial forces and torques directly at the bit and at the reamer. The observed mechanical specific energy, drilling efficiency, and aggressiveness of both cutting tools over depth are measured. The model and the quality curves are used to predict the weight and torque distribution depending on the formation type at the bit and at the reamer. A comparison of the prediction to the measured data shows that the weight distribution is predicted with an error of 2% and the torque distribution is predicted with an error of 10.8%. The model accuracy is determined by introducing uncertain parameters into the model. The load predictions are again compared to the measured data. Using the coarse parameter set, the mean prediction error increases to 13%, which is very good, considering the simplifying assumptions of the model. The validated model and the new quality curves enable an optimal choice of bit and reamers. The presented approach is fast and user-friendly and perfect for an application in advisory software in the well-planning phase. The increased reliability due to less mechanical overloads leads to reduced maintenance costs and less non-productive time of the reamer BHAs.
- North America > United States (0.28)
- Asia (0.28)
- Europe (0.28)
- Well Drilling > Drilling Operations (1.00)
- Well Drilling > Drillstring Design > Hole openers & under-reamers (0.91)
- Well Drilling > Drillstring Design > Torque and drag analysis (0.68)
Robust Design of Rotary Steerable System RSS and Revised Drilling Procedure Deliver Superior Performance in a UAE Onshore Field.
Al Mutawa, Ahmed Abdulla (Abu Dhabi Co For Onshore Petroleum Operations Ltd ADCO) | Quintero, Fernando (Abu Dhabi Co For Onshore Petroleum Operations Ltd ADCO) | Awad Mohamad, Abdul Salam (Abu Dhabi Co For Onshore Petroleum Operations Ltd ADCO) | Le, Khoa P. (Schlumberger) | Cantarelli, Elena (Schlumberger) | Thavaraj, Lambo (Schlumberger) | Dimas, Miron A. (Schlumberger) | Kojadinovic, Nenad (Schlumberger)
Abstract Rotary Steerable System (RSS) has been used for quite some time in the industry and in UAE onshore fields. But as the wells become increasingly more complex operators are forced to look into upgraded technologies to expand the envelope beyond the known limits, often implying more complex and costly bottom hole assembly (BHA). At the same time the current oil price situation make it extremely difficult for operators to justify any increment of Authority for Expenditure (AFE) or to take the risk of experimenting new solutions that could potentially increase non-productive-time (NPT), even if for just limited period until the learning curve is established. This case study demonstrates that adopting both fit for purpose technology and invisible lost time (ILT) reduction strategy can yield tremendous performance improvement delivering wells ahead of AFE. A preliminary field analysis carried as first thing to understand the field drilling challenges and performance limiters highlighted that both on bottom (rate of penetration, ROP) and off bottom time (connection time, wiper trips, circulation time, tripping time, etc.) presented areas for improvement. Throughout the life cycle phases of field development more complex reservoirs have been targeted for example thinner layers, multi-structural drain sections, extended laterals, etc. The demand of an RSS being able to drill smoother wellbore minimizing tortuosity and enabling longer sections and trouble-free tripping had gradually changed from being a "nice to have" feature to be a necessity not only to eliminate time waste but also to prevent costly stuck pipe events. The new high performance RSS (HP-RSS) and its enhanced software for trajectory control enabled a faster on bottom ROP by minimizing the need of directional driller intervention to correct the trajectory hence maximizing on bottom time. The enhanced directional control translated into smoother wellbores resulting in reduced friction factors and torque and drag which eliminated the need of wiper trips and decreased tripping and connection times. In parallel with this also drilling and connection procedure were revised, utilizing torque and drag real time monitoring to optimize connection time. The expanded envelope of HP-RSS also enabled further improvement of hydraulics for effective hole cleaning while drilling minimizing the hole conditioning time on connection. The advantage of having superior quality wellbore extended also to post drilling phases, for example it enabled a faster and trouble-free running of complex smart completion reducing HSE risks and further impacting AFE. In summary, the HP-RSS enabled superior performance saving $287.5K for an invidual well. The total amount of saving projected over a year in this field is estimated to be around $ 2.9M. Efficiency and reliability are keys to lower costs and increase profitability in oil and gas operations. This paper introduces a novel approach that aim to expand technical confidence to drilling and reservoir management to target more challenging drains sections with higher productivity.
- North America > United States (1.00)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.16)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- (2 more...)
Casing Swivel Tool Greatly Expands Liner Deployment Capability in the Giant Offshore Oil Field Abu Dhabi Resulting in a World Record Single-Run 6-5/8 Inch Lower Completion
Ryan, James Thomas (ZADCO) | Alvarez, Juan (ZADCO) | Clews, Matthew (ZADCO) | Reichle, Melanie (ZADCO) | Szary, Tomasz (ZADCO) | Deschamps, Benoit (Rubicon Oilfield International) | Espeland, Kent (Rubicon Oilfield International)
Abstract Extended Reach Drilling (ERD) and Maximum Reservoir Contact (MRC) well design can drastically decrease development costs. A critical ERD and MRC challenge is frictional drag encountered when running long casing and liner strings. If the frictional drag becomes too great the string will stall before reaching total depth (TD), severely compromising the completion of the well. This paper presents the implementation of the casing swivel tool to effectively mitigate this friction risk. String rotation can provide a large reduction in axial drag by shifting the friction vector to primarily affect the torsional direction. Full string rotation offers the largest benefit, but the torque required often exceeds both the casing connection rating and top drive capability. The use of a swivel enables partial string rotation above the swivel to reduce the torque requirement. With increasing production lateral lengths the swivel was moved from the running string into the liner to increase the rotating length of pipe while managing rotational torque. The drill pipe swivel has a long history of effectively providing a reduction in axial drag by allowing for the running string to be rotated when running long MRC lower completion liners. As lateral lengths have increased from 10,000 feet up to 20,000 feet in Extended MRC (EMRC) wells, the ratio of liner length to running string length has greatly increased. To accommodate this shift in well design the swiveling point needed to be pushed deeper into the well, from running string to the liner. The fit-for-purpose design of the sacrificial casing swivel allows it to be integrated permanently into the completion and enables increased partial string rotation. To date the casing swivel has been deployed on eight wells, including a world record single-run 6-5/8″ production liner. In one well, the liner stalled and only reached TD after engaging the swivel. The use of the casing swivel has reduced the required well count and capital investment by enabling lateral sections of up to 20,000 feet while also decreasing drilling risk due to less overburden drilling. The application of casing swivel in the Giant Offshore Oilfield Abu Dhabi was a first for this size and length of lower completion liner. The casing swivel has become a key enabler to maximizing the length of production laterals resulting in substantial well construction cost savings.
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- Well Completion > Completion Selection and Design > Completion equipment (1.00)
Abstract This paper presents the modern and fit for purpose methodologies, challenges with mitigation, special consideration from geological, drilling and completions to successfully deliver first deep horizontal well with lateral length of ~1300 m and open hole multistage fracking in tight carbonate reservoir in Lower Indus Basin of Pakistan. The paper also discusses economic feasibility of making re-entries into suspended vertical wells in generally high cost services infrastructure in Pakistan. The methodologies include special deliberations on; scenario based Geomechanics Modelling, Wellbore Placement Optimization along with economic analysis by using Re-Entry versus New Well, Formation Behaviors, Drill String Design, Drill Bits Design, Hydraulics and Torque and Drag (T&D) modelling with friction factor calibration, Drilling Fluid and Strategies, Downhole Problems & Mitigations, Wellbore Quality for Open hole Multistage Fracking – All challenges, associated risks are discussed and mitigated in detail. There were two main challenges in the wellbore placement; first is the requirement of wellbore to intersect maximum critically stressed fractures that required a new wellbore to drill and intersect but the economics of new wellbore was not feasible. Drilling team optimized the placement of the well and utilized an existing suspended wellbore to align well trajectory without compromising multistage fracking requirements. This had significantly reduced well cost and enabled the operator to proceed further. The second challenge was the wellbore failure that might have compromised hole quality and multistage open hole fracking on which the project economics based heavily. Two different fault regimes were present around the well that made the placement of wellbore more challenging. Wellbore trajectory was refined with multiple sensitivities of Geomechanics to fit the safe mud weight window. The LWD suits were run to enable the Geosteering in to sweet fractured zones. T&D model was developed and calibrated at real-time to take decisions. The drilling fluid was designed with special additives to encompass high temperature and stress caging of formation to prevent wellbore failure as well as to reduce Torque and Drag. Bit designs are also revamped that successfully drilled high UCS formations with minimal thermal cracking & favoring the RSS system to achieve landing the full lateral within top 30 m of formation. All aspects were thoroughly addressed and mitigated successfully resulting in to successful deliverables of the well project within the stipulated time and cost. The holistic approach presented in this paper had addressed special considerations to be given to successfully deliver horizontal wells with multifracking in tight gas reservoirs in Pakistan by rerunning economic sensitivities of already suspended wells in premature tight gas fields that restrained operators to further work on development due to failure of earlier similar projects and negative economics.
- Asia > Pakistan > Sindh > Lower Indus Basin > Goru Formation (0.99)
- Asia > Pakistan > Lower Indus Basin (0.99)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- Well Completion > Hydraulic Fracturing (1.00)
Abstract Well X is a deepwater exploration well with the carbonates primary target. The water depth ranges from 2700 to 3400 ft and the well was drilled vertically to 14630 ft MD. The main objectives of this operation was to optimize drilling performance while maintaining safe drilling practice and minimize potential failures. One of the ways to optimize the drilling is to have an excellent bit selection to determine the best bit for the application. Traditionally, due to limitation of the data, bit records from offset wells or fields becomes the only main source to select a bit. But sometimes, the selection becomes trial and error because of the availability of the data for evaluation. A Rock Strength Analysis (RSA) software now becomes a mandatory requirement for the pre-job planning to select a bit. Using the log data from offset wells, a bit selection software based on Unconfined Compressive Strength (UCMPS) calculation was used to optimize the bits for all section of Well X. The Dynamic FEA Modeling has also been used to contrast the drilling dynamics using several bit options for each section. The analysis is capable to simulate downhole drill string behavior with detailed components model including bits, reamers, driving systems, and all of the BHA components up to the surface. It includes axial, lateral, and torsional vibrations check, and also providing safe drilling parameter roadmaps to be applied in the field. The simulation is based on the cutter-rock interaction data from lab-test and has a wide range of lithology to make the result as accurate as possible. The integration between the RSA software and the Dynamic FEA Modeling resulted the best bit and parameter roadmaps for this application. Compare to the traditional way, this integrated method can reduce the risk of having poor bit performance in the field. The recommended bit and parameter guidance for each section was then applied to drill Well X and generated satisfying ROP without any NPT related to bit performance. The bits also came out from the hole with 1-1 average dull grade due to the excellent stability of the drilling system. The hard carbonates formation target in 8.5-in and 6-in section was successfully drilled in one run to TD with low shock and vibration. Even the bits only consume 3-6% of total drilling cost, it has a huge effect to the drilling performance. Combination of RSA and Dynamic FEA Modeling in bit selection process becomes a very effective practice to prepare an exploration drilling program with limited offset well data.
- Geology > Geological Subdiscipline > Geomechanics (0.86)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock (0.54)
Abstract Hydrocarbon exploration in Brunei has resulted in sophisticated drilling projects highly dependent on integrated environments, real-time decisions, and top-class drilling engineering. During peak activity in 2011 and 2012, an operator faced a declining performance in well construction projects caused by well-related drilling issues in extended reach drilling (ERD), snake, fishhook wells, leading to an unnecessary increase of total well costs. Managing the previously mentioned risks to reduce non-productive time (NPT) was the main driver for building an integrated environment for real-time decisions (IERTD), a new concept to optimize drilling operations by facilitating the decision-making process while maximizing the value of historical and real-time data. The pre-existing real-time operation center was integrated into the operator's performance process where all workflows were redesigned to help ensure focus on cross-department value, risk mitigation and real-time interventions, instead of reporting and low-value interventions. Novel and innovative application of monitoring software technology helped align well teams to actual versus plan engineering models, helping ensure faster and reliable data analysis, providing teams better visibility of well status, allowing improved decision making. Two years after the implementation of the IERTD, the operator experienced a reduction by 10 times in terms of leaving a bottomhole assembly (BHA) in the hole. The number of stuck pipe events was reduced by 67%, by improving the quality of information for decision makers and controlling the risk associated with the well challenges. The last 36 wells (included in this study) were drilled with zero NPT associated with drilling dynamics. The operation significantly benefited from the continuous flow of reliable and accurate processed information that allowed every final user to dispose the adequate tools to respond on time. This paper illustrates the techniques, technologies, and fundamentals behind the successful operation of the IERTD and how the interaction of these innovative concepts may contribute to operational excellence in future drilling projects.
Drilling Optimization to Overcome High Torque Problem: Lesson Learned on Kujung First Offshore-Near HPHT-Horizontal-Critical Sour-Slim Hole Development
Rizkiani, D.. (HCML) | Yustendi, K.. (HCML) | Rusli, B.. (HCML) | Mbouw, A. N. (HCML) | Mcken, D. R. (HCML) | Effendi, H.. (Baker Hughes) | Zulkarnain, S.. (HCML) | Soufanny, A.. (HCML) | Yang, Z.. (HCML) | Tian, Y.. (HCML) | Lian, J.. (HCML) | Maladi, A.. (Husky) | Diemert, A. P. (Husky) | Fadil, M.. (SKK Migas) | Utomo, P. P. (SKK Migas) | Yudento, S. D. (SKK Migas) | Mahry, A.. (SKK Migas)
Abstract BD Field is the first development project of Husky-CNOOC Madura Limited (HCML) in Madura Strait, Indonesia which has a pressure of 8,100 psi and a temperature of 300°F. This Kujung gas reservoir contains of 5.5% CO2 and 5,000 ppm H2S, indicating that the reservoir is near High Pressure High Temperature (HPHT) and critical sour environment. This paper describes the best practices, lessons learned and strategy to control drilling issues such as slim hole, horizontal, near High Pressure-High Temperature, high density, and sour/acid gas environment to achieve the well TD with torque and ECD limitation, without compromising production target. Kujung reservoir section was drilled with an overbalance mud system as per CNOOC HPHT and sour well requirement. Drill-In fluid (DIF) system treated with potassium formate and manganese tetraoxide as weighting agents was chosen for drilling the 5-7/8-in. reservoir section. Throughout the drilling operation, higher torque and ECD value was identified compared with Torque and Drag (T&D) Calculation and Hydraulics simulation. This can lead to shallower TD decision, which has consequence of possibility not achieving initial target depth/production. Calibrating T&D model using the pickup/rotate/slack-off value from actual measurements on both cased and open holes was done in order to match the model with actual condition. Several analysis and review of all possible causes was performed, including performance of solids control equipment, inadequate hole cleaning, dog leg severity, wellbore direction and/or formation lithology changes. T&D and hydraulics simulation was also performed to foresee the possible operation limitation with several lateral lengths to ensure having successful drilling operation without compromising both operational safety and future well production. Based on the original model, with friction factor values of 0.25 (cased hole) and 0.35 (open hole), 1000-1500 ft lateral length of 5-7/8-in. slim hole section can be achieved. However, with calibrated T&D model, friction factor values were almost double the original model. Comprehensive planning was done to accomplish the drilling objectives, such as re-plan well trajectory to reduce dog leg severity, selection of drill fluid lubricant additives to ensure its stability at pH > 11 environment as planned to control sour gas and compatibility with other products, maximize centrifuge usage to minimize excessive LGS build-up caused by successive and repetitive mud system re-use for batch drilling operations, and diluted system using rehabilitation mud. Reduced friction factors and decreased torque values were the key parameters to successful drilling through the updated planned horizontal length. In terms of gas well production, the objective of well productivity was achieved during unloading operation when gas production result from the wells yielded higher Absolute Open Flow (AOF) as compared to the planned target. Hence a successful BD wells had been delivered to production.
- Europe > United Kingdom > North Sea > Central North Sea > Moray Firth > Moray Firth Basin > Block 13/22a > Captain Field > Captain Formation (0.99)
- Asia > Indonesia > Java > East Java > Pangkah PSC > Kujung Formation > Kujung-1 Formation (0.99)
- Asia > Indonesia > East Java > Java Sea > Madura Strait production sharing contract (PSC) > BD Field (0.99)
- Well Drilling > Well Planning > Trajectory design (1.00)
- Well Drilling > Drillstring Design > Torque and drag analysis (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- (4 more...)