bluuebunny/crossref_metadata_2025_split huggingface dataset:
Step Change In Time Efficiency Using An Innovative Leap-Frog Rig System In Yemen
Authors: Diggins E. , Frail O. , Sawa M. 
Published: December 2007

Abstract
Yemen Masila Block 14 has been actively explored and developed since 1987 by Operator Canadian Nexen Petroleum Yemen (formerly Canadian Occidental Petroleum Yemen), and partners Occidental Petroleum and Consolidated Contractors (Oil & Gas) Company. Previous drilling optimisation initiatives have reduced typical well drilling times at Masila from over 30 days on early wells to 14 days in 1999. Presently, a leap-frog drilling rig system is being used to reduce drilling operations time on development oil producer and water injection wells even further. Comprising of two complete drilling rig units plus a partial drilling rig system, it is an excellent example of cooperation between Operator and Contractor to achieve a win-win situation. The initial and primary reason for use of this drilling rig system was to reduce the rig out/move/rig up time spent between wells by the drilling rig packages. A more recent, although equally as important initiative, has seen the leap-frog rig utilized to drill the well surface holes, run and cement surface casing strings, nipple up and pressure test blowout preventers, and run the next hole section drilling BHA in the well ready for drill out. On average, use of this drilling rig system has saved 2.5 rig days per well compared to the utilization of conventional drilling rig systems at Masila. During an annual 75 well development drilling program with a 60% leap-frog drilling rig system utilization, approximately 112 rig days can be saved. This enables an additional eight wells to be drilled each year, assuming a 14 day well spud to spud drilling time (realistic for 6500 foot development wells at Masila).
Development and Performance Testing of the Hex Mud Pump
Authors: Kverneland Hege , Kyllingstad Åge , Moe Magne 
Published: December 2007

Abstract
This paper focuses on the development process of the Hex pump. Computer assisted analysis has been used extensively to optimize the pump structure and vital parts with respect to weight, strength and life. Interactive computer programs for replacing paper based documentation and service manuals have also been developed.
Performing eleven subsea interventions in fifteen days
Authors: Olsen Terje , Mjøs Harald Kvammen , Nergaard Arnfinn 
Published: December 2007

Abstract
Between 27th August and 12th September, 2001, Norsk Hydro performed eleven subsea well interventions in fifteen days in the Troll Oil field, West Norway.
The work was done from Smedvig's 5th generation, DP, dual derrick semisubmersible West Venture.
The selection of the strategy of using a high-spec, fullblown drilling and completion vessel was initially based on a budget of nineteen days for a total of eight interventions. It was later decided to include three more wells in the campaign. Performing eleven interventions in fifteen days implied an average of 43 % time saving relative to the budget.
This paper describes the scope that was covered, and the way the overall campaign took maximum advantage of the DP and the dual activity features of the West Venture.
The paper also presents a simplified comparison between the West Venture and the competing concepts: an anchored single rig semisubmersible, a DP single rig semisubmersible and a subsea wireline monohull vessel.
The comparison proves that the West Venture will normally outperform all known existing competing concepts through a very significant reduction of the overall time for the operations. A direct comparison with an anchored, single derrick rig yields a 70 % time saving thanks to DP and dual activities.
Lost Circulation Assessment and Planning Program: Evolving Strategy to Control Severe Losses in Deepwater Projects
Authors: Sanders W. Wayne , Williamson Roger N. , Ivan Catalin D. , Powell Donald 
Published: December 2007

Abstract
There was a time when simply dumping some mica or nut hulls down a wellbore was a standard procedure for stopping mud losses. Certainly, these materials still work – for some applications. But, many of today's drilling operations bear little resemblance to that not-so-distant past. The industry is accelerating its activities in deepwater and depleted zones, both of which present narrow operating limits, young sedimentary formations, and high degree of depletion overbalanced drilling. All of these now-common conditions are ideal for fracturing and lost circulation.
Drilling through and below salt formations presents a host of technical challenges as well. The thief zone at the base of the salt can introduce severe lost circulation and well control problems, often resulting in loss of the interval or the entire well. Controlling losses in this zone has proven to be extremely difficult. Very few lost circulation remedies have been successful, especially when using invert emulsion drilling fluids. The lost time treating severe sub-salt losses can last for several weeks, with obvious cost implications, especially for deepwater drilling operations.
This paper reviews the methods applied to avoid lost circulation in the sub-salt thief zone, as well as in the subsequent intervals for a Gulf of Mexico deepwater project and discusses the time and cost savings obtained. For maximum success in these situations, emphasis has been placed on assessment and planning rather than individual lost circulation products.
The authors will detail the Lost Circulation Assessment and Planning process that has been employed to explore and evaluate specific lost circulation problems and link them to existing products, systems and services. The integrative pre-planning process analyzes offset histories and formation data not only to identify risk zones but also to gather information on the exact fracture and pore size as well as fracture density. Afterward, detailed interval-specific decision-tree charts are developed for stopping losses encountered while drilling or tripping in.
In addition to discussing the application of this Assessment and Planning process, the authors will outline the lessons learned on the deepwater project, featuring pre-planning issues geared toward ensuring circulation is maintained throughout the wellbore.
A Multilateral Application in a Limited Hoisting Capacity Environment
Authors: Brister Ray , Bonner Julie , Broderick Mike 
Published: December 2007

Abstract
Technology suppliers have produced special systems to handle a wide range of typical multilateral applications. One of the less typical applications is an environment where rig capacity, specifically hoisting capacity, is a limiting factor. There is currently no prefabricated multilateral junction that does not require the ability to reciprocate and rotate the pipe to ensure proper downhole orientation. Even if the junction orients perfectly on the first attempt, confirmation by picking up and resetting is recommended with some systems. The hoisting capacity limitation in this case made reciprocation and rotation impossible in conventional well procedures. The only recourse was to focus on reducing hookload and friction in order to install the multilateral junction, which, in this case, proved very challenging. All available methods were employed, equipment was modified, and careful calculation was made to mitigate any possible equipment failure.
There are various ways to address hoisting capacity problems. Among them are weight reductions, lubricants, and torque reduction additives. In this case history, each of these primary methods was employed to install a hook-type TAML Level 3 multilateral junction (Chambers1 and Hogg2) resulting in a first for the operator, the service company, and for Level 3 systems in general.
Optimizing the Well Construction Process: Full-Waveform Data From While-Drilling Seismic Measurements in the South Caspian Sea
Authors: Haldorsen Jakob B. U. , Esmersoy Cengiz , Hawthorn Andrew , Krasovec Mary L. , Raikes Sue , Harrold Toby , Day David N. , Clippard James D. 
Published: December 2007

Abstract
Recent advances in logging while drilling have enabled the development of a seismic tool that acquires and transmits seismic data in real time during the drilling process. Examples of this technology demonstrate the use of this service to significantly reduce risk and uncertainty, enabling better decision making during well construction operations. Operationally, the service runs with no interference with normal rig operations.
This technology can have a significant impact on the cost of exploration and development drilling, particularly in the deepwater environment and other areas with significant seismic uncertainties.
The service was first used to drill a wildcat well in the South Caspian Sea. The well was deviated to intersect the reservoir section within a steeply dipping structure at about 4500 m true vertical depth (TVD) while avoiding faulting, high pore pressures, and areas of poor seismic data quality in the overburden at the crest of the structure. The key product of the new seismic tool, real-time check-shot data, was used to position the drill bit and the borehole on the seismic section used to plan the well.
Furthermore, an analysis of the seismic waveforms recorded in the tool memory demonstrates the capability of this technology to produce data of sufficient quality to allow imaging of the formation ahead and to the side of the bit. Images from the tool have higher resolution and good ties with the migrated surface seismic images.
Future advances in technology offer the exciting possibility of imaging significant distances ahead of the bit in relevant real time.
Application of Real-Time Resistivity and Annular Pressure Data in Reducing Lost-Circulation Events
Authors: Akamine Andres Y. , Bratton Tom , Onyia Ernest , Romanchock Mark 
Published: December 2007

Abstract
Lost circulation is one of the major risks associated with drilling in a deepwater or subsalt environment. The downtime spent regaining circulation and the associated well control issues increase the already high operating costs and introduce critical safety concerns. This paper illustrates how formation resistivity and annular pressure measurements, combined with time-lapse logging data, can be used to determine a more accurate fracture pressure, enabling cost-effective real-time drilling decisions.
Two examples are presented to demonstrate that an analysis of the resistivity and pressure data, viewed in both time and depth domains, contributes to a better understanding of fracture behavior. Lost-circulation problems occurring in weak formations far below the casing shoe can be located with logging data. Additional information enables relevant-time drilling decisions such as selecting proper mud weight, spotting fluids, and optimizing cementing programs.
The first example shows how abnormal real-time resistivity readings, suggesting the initiation of fractures, were confirmed with time-lapse measurements made while tripping out of the hole. The real-time resistivity data showed elevated resistivities suggesting fracture growth. This interpretation was confirmed with time-lapse measurements. The analysis provided the location of the problem zone, the formation type, and the wellbore pressure activating the fractures. In the second example, a minor water kick prompted the acquisition of a real-time openhole leakoff test followed by real-time resistivity logging. The additional information provided a better understanding of the initiated fracture characteristics and enabled drilling the section to total depth without mud losses.
A New Look for an Old Field – Multilateral, Underbalanced, Semi-Short Radius Drilling Case Study: Installation of a Seven Leg Multilateral Well
Authors: Lee Dean , Brandao Fernando , Sotomayor Gabriel , Lucena Humberto , Filho Paulo Silva 
Published: December 2007

Abstract
The purpose of this paper is to review the planning, execution and results of a Seven Leg, Semi-short Radius Multilateral Well drilled underbalanced in a very mature field in Northeast Brazil. It will explain such details as … why multilateral?? … why semi-short radius?? … why underbalanced?? … in an effort to explain the many thought processes and considerations when designing and planning drilling operations in depleted reservoirs.
Accessing Deep Reservoirs by Drilling Severely Depleted Formations
Authors: van Oort E. , Gradishar J. , Ugueto G. , Cowan K. M. , Barton K. K. , Dudley J. W. 
Published: December 2007

Abstract
In many maturing prospect around the world, operators are facing the challenge of having to drill through highly pressure-depleted formations in order to access lower-lying hydrocarbon-bearing zones. New technologies such as expandable casing are now becoming available to allow for extensions to conventional well designs in order to deal with depletion. However, before one can case off depleted formations, one first has to successfully drill them.
This paper highlights key aspects in the planning and execution of the Ursa A-11 well, which was drilled through a 5500 psi depleted sand to a deeper horizon. Drilling complications included risks of excessive mud loss, internal blowout and differential sticking on the depleted sand. Moreover, fracturing of the depleted sand carried the risk of jeopardizing production at a nearby horizontal well. Key factors in the successful drilling of the Ursa A-11 well included special drilling fluid design, rock mechanics study, pro-active use of borehole strengthening technology, integration of supplier and operator expertise, and excellent communication between all parties involved.
Thermal and Mechanical Considerations for Design of Insulated Tubing
Authors: Pattillo P. D. , Bellarby J. E. , Ross G. R. , Gosch S. W. , McLaren G. D. 
Published: December 2007

Abstract
Of the several options for controlling temperature in a well, vacuum insulated tubing (VIT) has proven useful in a number of applications. Use of VIT, however, necessitates unique design considerations, from both a thermal and mechanical perspective.
This paper describes the application of VIT for a particular purpose – to minimize temperature change, and associated annular fluid expansion pressures, in a deep water well design. The specific application, however, lends background to more general design considerations associated with VIT. Thermally, the importance of heat loss at the couplings to the overall design is discussed, using both numerical analysis and experimental results previously reported in the redesign of wells for the Marlin TLP. Mechanically, a detailed examination of the loads to which VIT may be subjected also uncovers special considerations.
Control of Contained-Annulus Fluid Pressure Buildup
Authors: Williamson Roger , Sanders Wayne , Jakabosky Troy , Serio Michael , Griffith James E. 
Published: December 2007

Abstract
Fluid trapped in the annulus of subsea wells can cause casing strings to fail. This condition occurs when casing annuli attain a closed-volume circumstance (when a well is cased, cemented, and head seals are set). During production, the heat transfer of the produced fluids to the casing strings causes the trapped fluid to increase in pressure. This condition is magnified in deepwater because annular fluids are cooler due to the cold deepwater environment. Laboratory testing indicates that thermal expansion of these fluids can cause trapped water- or oil-based fluids to increase in pressure above casing-collapse pressure, resulting in annular pressure buildup (APB).
This paper outlines a simple laboratory procedure and resulting data to determine the resulting trapped-volume pressure. Data from eight fluid combinations are presented. The temperature change during testing is an increase from 80°F to 230°F. The testing relates to the conditions commonly found in deepwater Gulf of Mexico.
The laboratory data obtained from this testing was used to design a spacer system for Walker Ridge 285 #1, a deepwater, subsea well located in the Gulf of Mexico. This paper also presents the job design and related procedure for the executed spacer system.
Casing-Conveyed Perforating System Presents a Unique Set of Drilling and Cementing Challenges: A Case History Study – Kenai Gas Field, Alaska
Authors: Garner J. Jay , Eller J. Gary , Tank Willard J. 
Published: December 2007

Abstract
Three wells have been successfully drilled, cemented and fracture stimulated in the Kenai Gas Field utilizing an industry unique Casing-Conveyed Perforating System (CCPS). This revolutionary system consists of perforating guns external to the casing and integral valves in the casing for zonal isolation while fracturing. During completion operations all downhole equipment is remotely actuated without wellbore intervention. In addition, downhole sensors were run on all three wells providing monitoring of bottom-hole pressures and temperatures during cement operations, as the cement cures, during stimulation operations, and ultimately over the productive life of the well.
Special characteristics of the CCPS, such as the need for precise depth control and irregular geometry, present a unique set of drilling and cementing challenges compared to conventional casing strings. For the case history wells reviewed in this paper a total of 43 perforating modules have been deployed with 15, 12 and 16 modules run in the KBU 42–7, KBU 24–6 and KBU 44–6 wells respectfully. Meticulous pre-planning by a multi-disciplinary team of professionals provided solutions to the many challenges encountered. This paper provides detailed descriptions of the three CCPS wells drilled to date in the Kenai Gas Field, including the drilling, running and cementing requirements and the solutions developed and utilized in field operations. Each of the three CCPS wells completed to date has been deemed engineering, operational and economic successes.
Smart Drilling with ELECTRIC DRILLSTRING™
Authors: Lurie Paul , Head Philip , Smith Jackie E. 
Published: December 2007

Abstract
This paper will present the results to date of a project to develop an electric drillstring, together with some ideas and visions of how this technology could make a step-change in well construction. The electric drillstring should enable electric power to be transmitted through the drill pipe, while simultaneously multiplexing data back to surface from the downhole drilling system. This could allow a range of improvements to the drilling process, that we shall call "smart drilling", which should result in reduced drilling costs and optimized well placement for maximum productivity.
The project has followed the normal phases in any technology development, but only the initial two phases of feasibility and benefit assessment have been completed. The initial phase was to learn what had been done in the past to transmit electrical power and telemetry in a drillstring, identify the key problems and try to come up with some novel solutions incorporating technical improvements from both within and outside the drilling industry. The key benefits of the new system were identified, together with a range of potential applications that could be available in both the short and longer term.
The heart of the system is a reliable electrical connector integral with a premium drill pipe thread that will behave like a normal tool joint during operation. This is combined with mid-body conductors, in this case sandwiched between a metal inner layer and the drill pipe body. The development of the first two prototypes, which are on the route map to the initial field test, will be discussed.
Smart drilling via an electric drillstring can offer a wide range of possible advantages over conventional drilling operations, which could include: Reduced drilling costs from the optimization of the drilling process by control of weight on bit using downhole traction or thrusters, and maintaining bit speed independent of flow rate.Reduced wellbore stability problems due to both reduced ECD via reverse circulation and knowledge of the pressure conditions from sensors distributed over the length of the well.Reduced costs by replacing wireline logging with realtime LWD systems.Reduced stuck-pipe in ERD-type wells from traction tools distributed along the drillstring.Improved well productivity from improved geosteering via immediate data feedback from the high quality telemetry path.The development of Seismic-while-drilling (SWD) utilizing downhole sources and recievers.The possible development of new sensors that take advantage of the excess power available downhole.
These concepts will be briefly discussed in the paper together with the results of an initial benefit assessment.
Bringing Efficiency to the Offshore Rig Contracting Business
Authors: Carter Steven M. , Ghiselin Richard G. 
Published: December 2007

Abstract
The worldwide offshore rig chartering business is a significant business with $7 billion to $10 billion in annual expenditures. A study of bidding and contracting practices reveals major inefficiencies in the processes involved in this business, and in the variability of economic decisions, as evidenced by fixture ranges of up to ± $55,000/day for rigs of similar capabilities.
The market lacks transparency. Rig chartering supply and demand have very different characteristics. While supply is essentially inelastic, demand is highly volatile. This creates complementary needs for operators and contractors.
Operators need: ■Knowledge of rig capabilities including recent contracts and activities.■Knowledge of rig availability and future commitments.■The ability to quickly develop multiple contingency drilling scenarios.■Easy collaboration with partners and colleagues.
Contractors need: ■Knowledge of upcoming drilling projects and rig capability requirements.■Knowledge of competitors' rig dispositions and capabilities.■Ability to manage their fleets.
Both need: ■Detailed current supply and demand and dayrate information in each market segment to facilitate tactical and strategic decision-making.■Standardized contracting processes.
Several companies are managing their rig contracting businesses online, using a real-time expert system to give them the insight they need.
Having the right rig for the right job creates tremendous economic advantages. Operators are able to use their drilling budgets more efficiently. Contractors are better able to match their fleets' capabilities with market conditions. This paper offers several examples of decisions that have benefited greatly from market transparency. For example, market insights were essential in helping to determine whether to invest in a rig upgrade or newbuild, as well as how much to invest. Similarly, the ability to lease rigs competitively on the spot market depends on access to market and competitive information.
This paper provides examples of efficiency improvements by both operators and contractors, as well as the methodology and results of price/risk analyses.