bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incentive Contract: A Contractor's Viewpoint
Authors: Geehan T. , Rospide J. P. 
Published: December 2007

ABSTRACT
The use of incentive contracts in the drilling industry has become more common over the past few years. The introduction of performance related remuneration has developed for several reasons, the prime one being an effort to reduce overall drilling costs through increased efficiency. Another significant reason has been the operators desire to have their personnel concentrate on their core business which is finding and marketing oil.
This paper reviews the experience to-date and offers comment, from a drilling contractor’s viewpoint, on the types of incentive contracts presently in use. Discussion covers all phases from bidding to operation at the rig site. In particular certain work undertaken in France and Africa is discussed. The full range of incentive contract types are described, and the required change in attitude from the drilling crew is explained in order to allow successful completion. The need to maintain the correct approach in terms of safety and environmental awareness is also outlined..
A Multidisciplinary Approach to In-Situ Stress Determination and Its Application to Wellbore Stability Analysis
Authors: Ottesen S. , Kwakwa K. A. 
Published: December 2007

ABSTRACT
Recent technical papers have demonstrated development flexibility, and the potential for increased ultimate hydrocarbon recovery resulting from the application of extended reach and horizontal drilling techniques. Serious mechanical borehole stability problems, principally borehole collapse and tensile fracturing, can be associated with the drilling of such wells. The threshold drilling fluid pressures for the onset of each mechanism depend on the earth stresses and the mechanical properties of the formations. Hence, there is the need for careful engineering assessments and planning prior to drilling these wells. In this paper the methods of approach used in determining the magnitudes of the principal in-situ stresses by collating geological, drilling, leak-off, logging, well test, mini-frac and laboratory test data are presented. The results formed the basis for a detailed assessment of the mechanical stability of a planned horizontal well in UKCS Block 9/13. This horizontal well was later successfully drilled from a semi-submersible drilling rig, utilising carefully tailored drilling fluid densities based on borehole stability analysis.
Abnormal Formation Pressures in Post-Eocene Formation, Potwar Basin, Pakistan
Authors: Kadri I. B. 
Published: December 2007

ABSTRACT
The paper is based on experience gained during drilling in Potwar basin, on-shore Pakistan. The high cost of wells are primarily due to long drilling times resulting from extremely difficult drilling conditions, arising from abnormally high formation pressures. High pressure water inflows and loss circulations have led to premature abandonment of several wells on account of collapsed casing, bridging, caving, blowouts and cratering around the wells.
The post-Eocene Siwalik formations in the Potwar basin are notorious for abnormally high formation pressures and reversal of pressure regimes in the sedimentary sequence. Pressures close to geostatic have been encountered at shallow depths.
The aim of the paper is to take a close look at the mechanisms responsible for the generation of overpressure, identify problem areas, examine available options, keeping in view present drilling technology and equipment limitations, and finally recommend operational strategies to handle such situations.
Planning of wells, monitoring of drilling operations, selection of kick control procedures and wellbore integrity are considered to be critical factors for successful operations.
Integrated Driller's Cabin
Authors: McGill J. 
Published: December 2007

ABSTRACT
A new generation driller's cabin has evolved due to the introduction of more advanced drilling equipment and controls. Remote control of rig floor and derrick equipment will lead to a safer moreefficient andmore acceptable working environment.
Integrating both the drillerand assistant driller (ex. derrickman)into one work station within a driller's cabin,enables moreefficient control and communication between the two most important persons directly involved with the drilling operation.
How a Computerized Drilling System has Improved Drilling Performance
Authors: Arnold M. S. , Schilhab L. , White D. B. , Dudleson W. J. 
Published: December 2007

Abstract:
Recent advances in technology have given the drilling industry an opportunity to improve drilling performance. This new technology includes the application of innovative sensors, integrated computer systems, and advanced data processing software onboard the rig.
A complete system with all these facilities has been installed and operated by a drilling contractor on an offshore rig in the Middle East since mid-1989. The system has been used extensively by contractor and operator working together as a drilling team to increase safety and improve drilling performance.
An enhanced measurement of ROP gave drillers a faster indication of formation changes to avoid damage to PDC bits. With a new capability for interactive control of the monitoring system, contractor personnel had more credible input into the drilling process, which improved teamwork with operator personnel. Bit performance logs and well-to-well correlations were generated on the system's workstation to optimize bit selection.
As a result, drilling performance improved greatly over a series of wells in a field where the learning curve was thought to have been optimized. Resulting cost savings were substantial.
Metal Bearing Seal Technology Improves Drilling Efficiency of Rolling Cutter Bits in High-rpm North Sea Applications
Authors: Schmidt S. R. , Wittry A. E. , Burr B. H. , Kelly J. L. 
Published: December 2007

ABSTRACT
The impact of the metal bearing seal on rolling cutter bit performance at high rotary speeds has been dramatic. In the high-cost drilling environment of the North Sea, the metal sealed bit has proven its ability to extend rolling cutter bearing life at high rotary speed and thereby provide significant reductions in drilling costs. This improvement is encouraging more widespread use of these bits with downhole motors and steerable systems.
An analysis of recent run data from the Norwegian sector of the North Sea shows metal sealed rolling cutter bits can be used for a much greater number of bit revolutions than their elastomer seal counterparts and, consequently, footage per bit has more than doubled without sacrificing rate of penetration. Cost savings of up to $100,000 per well have been documented.
This paper describes the design of the metal sealed bit and its performance in the Ekofisk and Eldfisk fields.
North Sea Field Application of an Environmentally Responsible Water-Base Shale Stabilizing System
Authors: Alford S. E. 
Published: December 2007

ABSTRACT
Two exploratory wells were recently drilled in the North Sea which used a specially designed polymer drilling fluid to provide optimum shale and borehole stabilization. The first well was a deep Jurassic well in the Frigg and Balder area of the Norwegian North Sea; the second well was drilled in the Ekofisk area. (Figure 1.) FIGURE 1SHALE STABILITY MECHANISM
The mud for the reactive formation intervals was formulated to provide chemical stability for the reactive tertiary clays and claystones. Conventional fluid loss and rheology control polymers (polyanionic cellulose and xanthan gum, respectively) were used to achieve and maintain the required performance properties. Shale stability was obtained using a novel.additive composed of a polyvinyl alcohol polymer, potassium silicate, and potassium carbonate.
Shale stabilization is based on a unique new theoretical mechanism which was initially postulated in SPE 16687, "New Chemical Package Produces an Improved Shale Inhibitive Water-Based Drilling Fluid System," and presented at the 62th SPE Conference, Dallas, Texas, 1987 (Wingrave et al). Further details are included in this paper.
In the deeper intervals, high temperature polymer additives were used to maintain favorable rheological and filtration properties.
An injection system was used to inject prehydrated liquid polymer concentrate directly into the suction. This procedure was used to obtain optimum polymer efficiency and performance in the management of the drilling fluid system.
Drilling and drilling fluid performance data is presented for the 17.5", 12.25", and 8.5" hole sections. Mud weights from 10.0 to 16.0 ppg were required in the drilling program.
Drilling and fluid performance data from the first well (Frigg and Balder area), designated Well A, is compared with an earlier offset well in the same block, Well B, which was drilled with a conventional KCl/PHPA/Biopolymer/PAC polymer system.
Caliper data, borehole stability relative to exposure period, solids removal efficiency performance, wireline log quality, trouble-free casing and cementing operations, and minimal fluid-related hole problems while drilling - all provide supportive data indicative of superior chemical stabilization of the wellbore.
U.S. and Norway toxicity results support its use as an environmentally acceptable water base additive for offshore and onshore application.
Elements of Thermally Treating Oil-Base Mud Cuttings
Authors: Young G. A. , Growcock F. B. , Talbot K. J. , Lees J. , Worrell B. 
Published: December 2007

Abstract
This work shows that rotary retort distillation is a conceptually feasible alternative for removal of oil from cuttings produced while drilling with oil base mud. The work specifically examined the response and behavior of oil base mud drilled cuttings and associated fluids to heat in a tumbling bed. These test results established the temperature requirements necessary to clean oil base mud cuttings to various cleaning limits. Heat transfer coefficients have been calculated for the test apparatus. These heat transfer coefficients have been used to establish the size of a full scale unit necessary to process 15 metric tonne/hr of drilled cuttings. The recovered products, cuttings and oil have been evaluated for toxicity. The dried cuttings were evaluated with a metal leachate test to establish extraction procedure toxicity. The distillation products were chemically analyzed and the amount of noncondensable gas was estimated.
Finally a conceptual retort design is proposed for the offshore environment. Energy consumption and operating costs for a typical well are estimated.
New Oil-Base Mud Additive Reduces Oil Discharged on Cuttings
Authors: Friedheim J. E. , Shinnie J. R. 
Published: December 2007

ABSTRACT
A new additive reduces the amount of oil retained on drill cuttings generated by drilling with an oil-base fluid. The oil retention on drill cuttings phenomenon and the approach used in dealing with it in the field are reviewed with particular emphasis on the use of high water content oil-base muds. Laboratory and field data using this new additive to decrease total cuttings oil retention are described.
Detection and Monitoring of the Slip-Stick Motion: Field Experiments
Authors: Dufeyte M-P. , Henneuse H. 
Published: December 2007

ABSTRACT
By analysing simultaneous downhole and surface dynamic drilling measurements, it has been possible to characterize the drill string behaviour and, more precisely, the stick-slip motion.
Based on three thousand five hundred hours of real time field measurements, this paper presents the study of bit and drill string behaviour when the stick-slip phenomenon occurs.
Using correlations between downhole and surface recordings, it shows how, applied solely to surface drilling data such as torque and rotational speed, a simple mathematical calculation enables the detection of the stick-slip motion, estimation of its period, its sticking time and the maximum bit rotational speed.
It also demonstrates that it is possible to reduce and eliminate stick-slip by modifying certain drilling parameters such as weight on bit, rotational speed or mud characteristics. In addition, power swivel control can suppress the first mode but may also emphasize a higher mode of the stick-slip phenomenon.
Looking at the numerous hours of recordings which have been analysed, during 50 % of the time this phenomenon is seen to be permanently present while rotating.
As drill pipe fatigue and bit wear can be linked to the stick-slip motion, the possibility of controlling and limiting it by simple surface monitoring is a very attractive concept.
New Ultrasonic Caliper for MWD Operations
Authors: Orban J. J. , Dennison M. S. , Jorion B. M. , Mayes J. C. 
Published: December 2007

Abstract
An ultrasonic tool has been developed for MWD applications that simultaneously performs realtime bore-hole caliper measurements and realtime gas influx detection.
The caliper determines the ovalness of the hole with a high degree of accuracy and excellent vertical resolution. These measurements are transmitted to the surface and also used to compensate LWD measurements. Furthermore, with early and accurate real-time caliper measurements, bore-hole instability can be detected.
Real-time gas influx detection insures early and reliable gas kick detection and should provide a considerable improvement in drilling rig safety. The new tool is particularly useful for avoiding problems associated with shallow gas formation where response time for kick detection is critical.
Environmental Control Potential of Drilling Engineering: An Overview of Existing Technologies
Authors: Wojtanowicz A. K. 
Published: December 2007

ABSTRACT
The overview paper examines environmental control techniques associated with borehole technology. The overview includes two aspects of environmental control: surface discharge of pollutants from the drilling process, and subsurface interzonal isolation resulting from well completion.
The definition and objectives of the environmental control technology for oilfield drilling operations are presented first. Its preventive function is derived from modem concepts of source separation and recycling in addition to the conventional remedial function of waste disposal.
The use of systems analysis to define the environmental constraints in the drilling process places environmental control technology as an integral part of modem mud engineering. The technology serves to control volume and toxicity of active mud systems. In well completions, environmental control comprises well cementing technologies to control the hydraulic integrity of annular seals.
Described is the technological mechanism of the mud system volume expansion resulting from inefficient cuttings removal. Special consideration is given to drilling fluid properties such as dispersivity and dewaterability; their physical nature and control measures are discussed. Also presented are examples of recent research efforts to develop new mud systems that have properties of low dispersivity and high dewaterability.
The discussion on drilling fluids toxicity control includes recent developments in toxicity measurements as well as toxicity reduction through the use of low-toxicity substitutes or remediation mechanisms. Examined are recent research efforts to develop a simple toxicity test which can be deployed at well sites. These efforts are discussed in view of the search for a correlation between the field tests and the conventional Mysid test Also presented are examples of recently developed substitutes for diesel oil, metal and salt-related toxicity. Further discussion covers remediation methods for oil-base mud cuttings, and the role of surface mechanisms in oil removal from solids.
Part of the overview focuses on the mechanisms related to the integrity of borehole annular seals and subsurface migration of pollutants. Specifically discussed are recent developments in the methodology of Mechanical Integrity Test using the Cement Bond Log and the neutron activation techniques. Also included is a short discussion of potential applications of recently developed techniques to design the annular cement seal integrity.
Top-Drive Drilling Systems: Electric vs. Hydraulic-A Technical Overview and Comparison
Authors: Williams M. K. 
Published: December 2007

ABSTRACT
Since 1982 over 300 Top Drive systems have been installed worldwide, on virtually every type of drilling rig. An ongoing debate centres on the prime moverfor rotating the drill pipe. Should it be "electric" or "hydraulic"?
The purpose of this paper will be to provide a detailed comparison of both systems, outlining the advantages and disadvantages of both. Details of the designs, installation requirements, efficiencies, actual field performance and relative cost comparisons to install and operate will be presented.
The results presented will showthe relative merits of each system and technically compare the overall operational aspects of each system as reflected in the current drilling environment we are experiencing today. The data presented will provide the potential user with the necessary information to evaluate an application and select a system.
State-of-the-Art Trip Monitor
Authors: Bible M. J. , Hedayati Z. , Choo D. K. 
Published: December 2007

ABSTRACT
This paper describes a state-of-the-art trip monitor program which makes drilling safer and more efficient. The trip monitor program computes drillstring friction while tripping. The friction calculation is insensitive to the effects of wellbore geometry, buoyancy and BHA used. Volumes of mud and steel transferred into and out of the hole are accurately monitored to detect kicks and losses. The program is flexible enough to work automatically with all fill-up techniques. The program calculates swab and surge pressures in real time and uses pore pressure and fracture gradient information to calculate safe tripping speeds. A rig floor CRT display delivers answers to the driller which he can read at a glance.
This paper outlines the different features of the trip monitor program and the theory behind them. In particular, the friction analysis is discussed in detail to include the influence of the block sheaves and an imperfect description of the pipe geometry on the answer. Field examples are presented to demonstrate the usefulness of the method.
Keys to a Successful Cement Job for a Horizontal Liner on Statfjord A Platform, Well A-37A: A Case History
Authors: Torsvoll A. , Olaussen S. R. , Almond S. W. 
Published: December 2007

ABSTRACT
This case study provides complete details of the steps taken to cement a 700 meter horizontal section of 7in. liner on the Statfjord A Platform, Well A-37A. By properly addressing the four major problem areas associated with horizontal well cementing (displacement mechanics, cement slurry design, cement job simulation, and on-site job execution), a near perfect bond log and complete zonal isolation were obtained.
6,000-ft Water Depth Upgrade of the Sonat Discoverer 534
Authors: Karlsen G. , Sikes J. D. 
Published: December 2007

ABSTRACT
This paper discusses the upgrade of the Discoverer 534, from a turret moored 3500 ft [1100 m] rated drillship, to a fully dynamic positioned vessel rated at 6000 ft [1830 m] water depth. After the upgrade, the vessel commenced drilling in 3730 ft [1137 m] water depth which will be followed by a well in 5900 ft [1800 m] waters during the first quarter of 1991. This will be a world water depth record for a vessel with a 18-3/4 in. [476 irm] BOP stack and a 21 in. [533 mm] drilling riser.
Increasing Reach From 3,000 m to 5,000 m
Authors: Scott P. W. 
Published: December 2007

Abstract
Changes were made to drilling equipment and practices to be able to drill to 5000 metre radius wells from anoffshore production platform. Based on an optimised long reach well design, drilling equipment was sized and selected to achieve good drilling parameters and then integrated into a seven year old drilling rig. Drilling practices were modified to take advantage of the changes and a training programme assisted the smooth resumption of drilling.
The final cost of the upgrade project was US $9.5 million.
Improved Rig Safety by Rapid and Automated Kick Detection
Authors: McCann D. P. , White D. B. , Marais L. , Rodt G. M. 
Published: December 2007

ABSTRACT
Rapid kick detection is an essential part of rig safety. The smaller the influx when detected, the easier it is to control the well. The introduction of an extensive computerised monitoring system on a drilling contractor's offshore fleet has led to the development of displays and intelligent alarms designed to help drilling personnel detect kicks and losses before they would normally be apparent, thus increasing rig safety.
In this paper we describe an automated system with three independent monitors checking once a second for an influx into the well. Field tests and examples demonstrate the effectiveness of the intelligent alarm system.
The Active System Volume and differential flow (Row-out minus Flow-in) are continually monitored both during circulation and pipe connections. Whilst tripping the volume of drillpipe is measured accurately and is automatically compared with changes in the trip tank volume. A graphical representation of the difference between the two is given to the Driller, Rig Superintendent and operator representative, together with alarms when a consistent deviation is identified.
TOTAL’S concern for safety, especially on difficult wells, has led to the installation of the contractor's system on an offshore rig in Indonesia. The results of field tests on this rig are presented together with field examples of real kicks from other systems.
Development of Sour Service Drillstring With 110-ksi Yield Strength
Authors: Tsukano Y. , Asahi H. , Terasawa T. , Ueno M. 
Published: December 2007

ABSTRACT
A sour service drill string with 110 ksi [758 MPa] yield strength has been developed. The NACE threshold stresses are above 90% of the specified minimum yield strength (110 ksiC758 MPa]) for the tool joint and the drill pipe and above 65% for the weld area. Also, the sulfide stress cracking (SSC) resistance of the drill string was totally evaluated by full-size SSC testing. The practicality was confirmed through finite element analysis (FEA) and full-size performance testing (gas leak, full-size fatigue, full-size tensile, overmakeup and make-and-break testing).
New Lightweight Technology for the Primary Cementing of Oilfield Casings in Cold Environments
Authors: Harris K. L. 
Published: December 2007

ABSTRACT
New lightweight cement technology, based on increased cement fineness, has been developed in response to problems associated with cementing primary oilfield casings in cold environments. When low density slurries are required at low temperature conditions, adequate compressive strengths may be difficult to obtain. The new technology presented in this paper, called ultrafine cement, offers lightweight cement slurries (10.0 lb/gal-13.0 Ib/gal) which exhibit much higher early compressive strengths than conventional lightweight systems when cured in cold environments (40°F - 80°F).
By means of laboratory investigation, this paper introduces ultrafine cement as a unique lightweight primary cementing material. Performance properties of ultrafine slurries are discussed and comparisons to commonly used lightweight cements are presented.