bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methods and Tools for Cost Effective Subsea Inspection Planning
Authors: Descamps B. , Woolley K. , Baker M. J. , Corbett G. G. 
Published: December 2007

Abstract
International competition, and to some extent the CRINE initiative, have stimulated oil and gas operators to minimise production costs wherever possible. Underwater inspection, repair and maintenance (DRM) of the platform jacket consumes a major proportion of the overall maintenance budget and consequently any reduction in this area is likely to have a significant impact on overall costs.
All offshore jackets are inspected regularly to ensure structural integrity and satisfy the strict statutory requirements. Technical advances have been achieved in recent years, particularly in ROV capability, which have led to a general reduction in highly expensive diver time. However, it is widely recognised within the industry that inspection costs could be further reduced by combining such advances with a much more rigorous planning philosophy, the aim being to reduce the total amount of inspection activity whilst maintaining or improving the effectiveness of the work carried out.
Quest Consulting Ltd and Aberdeen University are working jointly on a Teaching Company Scheme, part funded by the Government, to develop methods and tools for targeting the inspection of offshore structures at areas of greatest criticality on a sound scientific basis. This paper presents the results of ongoing research and proposes that planned inspection should include a refined risk assessment to rank components and define the most appropriate inspection methods and optimum inspection intervals for a given structure. This will result in the most cost effective approach to underwater inspection being implemented.
Coiled Tubing Extended Reach Technology
Authors: Bhalla Kenneth 
Published: December 2007

Abstract
Coiled Tubing is used increasingly to service highly deviated and horizontal well. A limitation or horizontal displacement occurs because of the frictional forces between the coiled tubing string and borehole while running in coiled tubing. This causes helical buckling and can lead to lockup of the coiled tubing string, thereby limiting reach.
This paper will address the various techniques currently in use and propose new techniques to achieve additional reach. The topics that will be discussed are buoyancy reduction, friction reducers, optimal taper and pipe size of coiled tubing, straightening coiled tubing, downhole tractor simulation, flowing fluid, and pumpdown.
A tubing forces model has been developed that models these techniques. Results showing additional reach attained will be presented in the form of the surface weight prediction for commercial and conceptual wells.
CAN SMEs Survive Crine
Authors: Gray Andrew , Hay James , Marsh Richard , Punt Alistair 
Published: December 2007

Abstract
Small companies have been the source of much of the innovation that has helped to develop the North Sea. They have relied on the support, both financial and risk taking, of the oil companies to bring their ideas to the market. Much has been spoken and written about the changes in the mode of working in the North Sea and the increasing contracting out by oil companies, which comes in the various guides of partnering, partnerships, alliances, risk sharing and performance related contracts, MMSC contracts etc. All have certain common features, such as being large contracts with large companies for lengthy periods, possibly for the life of a field, and require some acceptance of risk by the contractor. There is now a question as to who will supply that support, Will the new buyers adopt this role, or will they stay with the tried and tested to minimise their own risks? CRINE also suggests standardisation which by definition kills innovation. Will this mean that no new small companies emerge and many existing ones go to the wall? Will this secure the future? Apart from a few expressions of good intent, for example, at the 1994 CRINE Conference, little has been said about the issues that these changes bring for small companies. These issues exist across the whole spectrum of the oil industry, but this paper looks at one area of activity which has largely developed in the North Sea, and which is one that has offered real hopes of exports - underwater operations, The issues facing three different types of small company are examined - one product development, one services, and one consultant engineering, The conclusion is that SMEs can survive CRINE, but only if they and the market adjust to the new circumstances.
Studies on New Gas Hydrate Inhibitors
Authors: Kelland M. A. , Svartaas T. M. , Dybvik L. 
Published: December 2007

Abstract
Traditional hydrate inhibitors such as methanol and glycols have been in use for many years, but at today's oil pricesjhe demand for cheaper methods of inhibition will be required. The development of alternative, cost-effective and environmentally acceptable hydrate inhibitors is a technological challenge for the oil and gas production industry. These new hydrate inhibitors can lead to very substantial cost savings, not only for the reduced cost of the new inhibitor but also in the size of the injection, pumping and storage facilities. Thus it is possible to redesign production facilities on a smaller scale. A few chemicals have been tested in field trials already with mixed success. Certainly, there is room for more active and cheaper inhibitors. We will review the relative merits of the two main types of hydrate inhibitor, "kinetic inhibitors" and "anti-agglomerators" regarding their applicability, and discuss how test results obtained in the laboratory compare to real field trials. We will also describe new techniques for comparing the effectiveness and activity of new hydrate inhibitors and present laboratory results on various chemicals. Patented examples will also be mentioned. Finally, a comparison of model systems with real fluids with regards to hydrate formation and inhibition will be given.
Downhole Swab Valve Aids in Underbalanced Completion of North Sea Well
Authors: Walker Tim , Hopmann Mark 
Published: December 2007

Abstract
As operators around the world continue to explore coiled tubing drilling and completions, one of the main benefits this technology has demonstrated is the ability to drill through the formation in an underbalanced situation. The benefit is somewhat minimized, however, if the well has to be loaded with kill weight fluid prior to running the completion or perforating. This paper will discuss how this problem was solved for one North Sea operator and how that solution can be extended to other operators.
Some Powerful Reasons for Adopting Front Tracking Simulation
Authors: Tyrie J. J. , Gimse T. 
Published: December 2007

Abstract
The advantages of Front Tracking simulation are becoming well known. This paper is directed towards demonstrating some of the advantages of front tracking simulation by briefly describing a field example of an infill well in the large Magnus Field operated by BP. This was not a test case conducted to prove the simulator but a case with the specific objective of reducing the risk associated with the infill well.
The Frontline simulator was used to investigate the movement of water in a specific layer of the Magnus oil reservoir around the PN5 infill well location on the west flank of the field. Sensitivities were conducted which reflected the geological uncertainties of the area with a view to assessing the possibility of the infill area having already been swept as water had swept through nearby wells. The PN5 block remained unswept in all sensitivities although some cases did draw water closer to the area. The PN5 area was found to be in a drainage area between a northern producer, A5, and a southern injector, D5, and would not be swept for some time without PN5.
This was the first Frontline simulation study to be conducted by BP in Aberdeen. Overall Frontline has proven to be a quick, alternative approach to assessing a reservoir sweep problem and readily provided well communication information which is not available from standard simulations. Frontline significantly reduced the uncertainty and the well was drilled shortly after the study and although part of one layer was swept the target layer was unswept and the well brought on stream in excess of 20 mbd dry oil.
Cost Reduction and Safety Improvement through Integrated Drilling Operations
Authors: Stromsnes O. , Stakkeland H. , Pedersen S. 
Published: December 2007

Abstract
A new concept that makes it possible to integrate all equipment and services in the drilling industry has been developed. Utilised to its full extent, this opens up for improved process information and advanced automation, with the possibility of running the operations from a central control room.
The intention behind the work has been to reduce the operational cost and improve safety.
Advances in Extended Reach Drilling – An Eye to 10 km Stepout
Authors: Ryan G. , Reynolds J. , Raitt F. 
Published: December 2007

ABSTRACT
This paper will present recent technological innovations which have been used to surpass previous extended reach records together with other technologies which are viewed as fundamental in overcoming current limitations for extended reach and designer wells. The paper will focus on three specific drilling applications which provide a range of options for operating companies with varying field development philosophies.
Drilling and Completing Wells for High Productivity in the Point Mclntyre Field: Strategy, Implementation and Verification
Authors: Bloys J. B. , Murphy J. , Weingarten J. S. , Wheatall M. W. 
Published: December 2007

Abstract
A proactive approach to economically improving well productivity was undertaken at the beginning of the development drilling program in the Point McIntyre field on the North Slope of Alaska. This paper describes the comprehensive approach, laboratory tests, field implementation, and well test verification of reduced skin damage. The approach was a combination of a minimally damaging KCl mud with limited leakoff, KCl in the cement and spacer, rapid drilling rates, and deep perforations. Laboratory tests of the rock and mud were performed before the onset of the drilling program, to identify potential damage mechanisms and to select the least expensive, least damaging, drilling mud. Field procedures were developed which ultimately led to open-hole displacement of freshwater mud to KCl mud just above the pay, which reduced the incremental cost by a factor of 2. The success of the drilling and completion strategy was demonstrated using pressure buildup tests to measure skin. Inexpensive pressure buildup tests were conducted prior to field startup, using in-house personnel and equipment, in addition to more conventional testing after field startup. Development well skins were compared with those of previous exploration wells and with water injectors which were drilled with a common low-solids non-dispersed freshwater mud. Although this reservoir would not normally be identified as particularly damage-prone, use of the KCl mud helped improve well productivity by almost 60% over wells drilled with the freshwater mud commonly used in the region. The well test and productivity data clearly justified the additional cost of using the more expensive drilling mud. Costly well stimulations were avoided, and infill drilling was deferred.
Experience With Drilling C-26A, A World Record Extended Reach Horizontal Well in the Oseberg Field, North Sea.
Authors: Andresen Svein , Hovda Sigve , Olsen Tor Lie 
Published: December 2007

Abstract
Well 30/6-C-26A was drilled to 9327 m measured depth in January 1995 from the Oseberg C platform in the North Sea. The well has a horizontal reach of 7853 m which is a new world record in Extended Reach Drilling, The last 2100 m were drilled horizontally in the reservoir 6 – 8 m vertically above the oil water contact. This paper will describe the planning phase as well as operational challenges experienced during drilling of this well.
An Integrated Approach to Evaluating and Managing Wellbore Instability in the Cusiana Field, Colombia, South America
Authors: Last N. , Plumb R. , Harkness R. , Charlez P. , Alsen J. , McLean M. 
Published: December 2007

Abstract
An integrated approach to evaluating the causes of severe wellbore instability in the Cusiana field is described. The field is located in a tectonically active region of Colombia. Deterioration of the hole during drilling operations has led to excessive nonproductive time and expensive wells. The scale of the problem is unprecedented in the world. In wells costing tens of millions of dollars, millions per well could be attributed to poor hole conditions.
This paper describes how the problem was addressed and what actions were taken to improve operational performance, resulting in reduced drilling costs. The improved understanding has contributed to better well planning, and improved drilling performance, and has underlined the need to consider all aspects of the drilling process to achieve improved hole conditions in a difficult geological setting.
New Concepts Lower Deep Water Drilling Costs
Authors: Jenkins Roger W. 
Published: December 2007

Abstract
Texaco Exploration and Production Inc. recently drilled a deep water location in Green Canyon 506 (Gulf of Mexico) with the Sonat Discoverer 534 drill ship. The well was drilled to below 21,000 ft measured depth in only 80 days. TEPI developed a simple well head system for containing shallow water flow zones. Underreaming and drilling was accomplished simultaneously which allowed the drilling time to be greatly reduced. A "thin is best" approach was used on the drilling fluid to promote solids removal efficiency. A unique incentive plan involving the contractor and key service providers was used to motivate rig employees.
Gulf Coast Section SPE Production Operations Study Group – Technical Highlights from a Series of Frac pack Treatment Symposiums
Authors: McLarty J. M. 
Published: December 2007

Abstract
One of the main functions of the SPE is to provide a means for collection, dissemination, and exchange of technical information and to provide technical forums that afford opportunities for members to maintain and upgrade their technical competence. The large chapters (such as Houston SPE) located near many oil company headquarters have the advantage of being able to bring together a cross section of service company and operator personnel representing operations and research from major and independent operators. This paper describes a series of 1-day symposiums on frac pack technology that were organized by the Houston-based Gulf Coast Section SPE Production Operations Study Group. These study sessions provided a means for the local members of the industry to further develop a new technology as a team. Publishing the major focus and contributions of the seminars will allow sharing of the technology with chapters outside of Houston.
Success Achieved in Lenticular Reservoirs Through Enhanced Viscosity, Increased Sand Volume, and Minimization of Echelon Fractures
Authors: Ely J. W. , Brown T. D. , Reed S. D. 
Published: December 2007

Abstract
A common trend in our industry is to minimize gel concentrations and utilize the lowest viscosity fluid available to place proppant. Barrett Resources Corporation has found, for lenticular microdarcy formations, that one of the keys for success is enhanced proppant transport. This is achieved incorporating stable gels which maintain greater than 1000 cps viscosity at bottomhole static temperature for the duration of the treatment. An extensive case study has been completed, involving over 500 fracture stimulation treatments in more than 175 wells, that illustrates the poor results achieved in the Williams Formation of the Mesaverde Group using low viscosity fluids. Low viscosity fluids invariably exhibit poor proppant transport. The statistical study shows that larger treatments utilizing "perfect proppant transport" fluids gain superior results. Based upon the case study, 100% economic success has been achieved upon incorporating stable fluids containing delayed breakers, reducing pad volumes to less than 5% of total job size, and minimizing echelon fractures while implementing a limited entry stimulation technique.
Hydraulic Fracture Reorientation in Primary and Secondary Recovery from Low-Permeability Reservoirs
Authors: Wright C. A. , Conant R. A. 
Published: December 2007

ABSTRACT
Hydraulic fracture orientation is critical to both primary and secondary oil recovery in low-permeability reservoirs. Incomplete and often overlapping drainage patterns under primary recovery, as well as inefficient sweep and premature water (or steam) breakthrough under secondary recovery are some of the common production problems that often result from hydraulic fracture reorientation. Often, hydraulic fracture orientation is measured on a few wells, and then generalized across the entire field under development. This characterization of regional fracture (stress) orientation is then assumed constant over the development life of the field. A wealth of recent' observations have definitively shown that fracture (stress) orientation in low-permeability reservoirs can be profoundly affected by production activities.
Hydraulic fracture reorientation has been observed on dozens of staged fracture treatments (in several fields) under both primary and secondary recovery. A summary of collected field data from three extensive field studies is presented. The production impact of fracture reorientation on both primary and secondary recovery schemes is addressed; and strategies are presented which utilize the recent findings for both enhancing primary recovery and mitigating some common problems with secondary recovery.
The discussion of reorientation mechanisms is greatly enlightened by recent data which reveals a startling correlation between observed fracture reorientation and indirect measurements of reservoir compaction.
The Development of Laboratory Correlations Showing the Impact of Multiphase Flow, Fluid, and Proppant Selection Upon Gas Well Productivity
Authors: Penny Glenn S. , Jin Liang 
Published: December 2007

Abstract
This paper describes the development and use of laboratory data to show the impact of multiphase, non-Darcy flow upon gas production from hydraulic fractures. In the work, the impact of proppant type and fracturing fluid damage upon non-Darcy flow and effective conductivity vs. closure, temperature and gas/water/oil ratios is shown for sands, resin-coated sands and ceramics with various fracturing fluids. Laboratory derived correlations are then used to predict gas productivity and economics under various conditions of multiphase non-Darcy flow and the predictions are compared to field examples.
The results of the testing show that multiphase non-Darcy flow dramatically increases the difference between the effective conductivities of various proppants at high closures. The laboratory data and field observations show that when this is taken into account, a premium proppant can show twice the production rate of commonly used sand products at high closures in gas wells producing as little as 10 barrels of water or condensate per MMCF.
Uncertainty Analysis of Borehole Stability Problems
Authors: Morita Nobuo 
Published: December 2007

Abstract
An uncertainty analysis is conducted for borehole stability problems based on a statistical error analysis method. The uncertainty analysis shows that the parameters impacting on the safe mud weight to stabilize borehoie are rock strength followed by shale swelling, in-situ stress, pore pressure, well inclination, and so on. Several procedures to improve borehole stability analysis are proposed.
Overcoming Interpretation Problems of Gas-Contaminated Cement Using Ultrasonic Cement Logs
Authors: Butsch R. J. 
Published: December 2007

Abstract
The primary objective of cement sheath evaluation logs is to determine whether the production or injection zones, as well as other critical zones, are hydraulically isolated. Ultrasonic measurements have been used in cement evaluation since the early 1980s, Ultrasonic tools evaluate the cement sheath by measuring the acoustic impedance of the material outside the casing. Cement has a higher acoustic impedance than drilling fluids or water, and gas has an acoustic impedance near zero. Gas-contaminated cement poses the main problem in interpretation of ultrasonic cement tools,
To understand the problem, the acoustic impedance of what might be in the casing-to-formation annulus must be considered. The acoustic impedance of cement can range from slightly over 3.0 MRayl to about 7,0 MRayl. Drilling fluids can be 1,5 MRayl to 3.0 MRayl. Water has an acoustic impedance of 1.5, and gas has an acoustic impedance of less than 0.04 MRayl. As long as there is sufficient difference between the acoustic impedance of the cement and the acoustic impedance of the liquid phase, channels in the cement can quickly be identified. In the case of gas-cut cement the texture of the material tends to be that of a honeycomb. The result is that each segment of the casing radius examined by the ultrasonic transducer may contain a combination of cement and gas, The acoustic impedance measured could be anywhere from that of gas to that of cement, depending on the percentage of the different materials contained in that small area. As a result, the acoustic impedance image displayed by the ultrasonic tools looks like a random pattern of cement, liquid and gas, but usually indicates that a channel is present. Because of the interpretation problems in gas-contaminated cement, it is frequently recommended that an attenuation-type cement bond tool be run in combination with the ultrasonic tool. The only advantage the attenuation-type cement bond tools have over the ultrasonic tools is that they are less affected by gas-contaminated cement,
This paper proposes a technique for using high-resolution ultrasonic data to identify gas-contaminated cement, while maintaining nearly the same vertical and radial resolution, thus allowing the identification of liquid-and gas-filled channels. The proposed technique allows improved interpretation of the high-resolution ultrasonic data when gas-contaminated cement is encountered. Even when attenuation-type logs are run, this technique will aid the interpretation, The results to date indicate that this technique can be applied to eliminate unnecessary cement squeeze jobs caused by misinterpretation of the ultrasonic data. Examples are shown to compare the technique to other cement log data and cement squeeze results.
Slimhole Cementing - Analysis and Possible Solution of the Problem
Authors: van Vliet J. P. M. , Bour D. L , Griffith J. E. 
Published: December 2007

Abstract
Very little quantitative data are available on how to cement slimhole wells while still adhering to good cementing practices. Therefore, a combined theoretical and experimental study has been carried out, from which a number of slimhole cementing guidelines have been derived. The analysed example case considered the cementation of a 3−1/2" liner in a 4−1/8" hole, in a relatively deep, high pressure, high temperature well drilled in a formation with minimal difference between pore and fracture pressure gradients.
It was found that a conventional (solids laden) high pressure, high temperature (HPHT) water-based drilling fluid cannot be fully displaced by the cement slurry, without exceeding the pressure limits of the formation. On the other hand, a potassium formate brine based HPHT drilling fluid can be displaced with close to 100% efficiency, even with sub-optimum cementation practices (i.e. no pipe movement, low annular velocity of the mud in the initial stage of the cementation). The low, flat gels and thin, tough filtercake greatly facilitate mud removal during cementing.