bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Unique Spinoff of Inflatable Packer Technology to Enhance the Ability to Circulate Casing Down on a Top or Side-Drive Rig
Authors: Stokley C. O. , Scott S. R. , Sanford L. B. , Jordan R. A. , Mounteer J. M. 
Published: December 2007

ABSTRACT
Problems are often encountered in running casing into a wellbore which require the "rig-up" of a circulating head in order to lower casing farther into the hole. A method of quickly and safely achieving circulation through the casing will be discussed in this paper, including tool development, deployment and field applications.
Back to the Basics: Planning the Operations for Drilling a Well
Authors: Chaney M. L. 
Published: December 2007

ABSTRACT
The reduction of drilling costs is more important than ever in the oil industry today. The use of basic planning techniques and communication with all drilling personnel cuts costs even further.
As in many operations which exist today, communications in the drilling industry are fine until getting down to the day-to-day portion of the operation-the very point where communication makes or breaks a business. Communicating and planning, what I refer to as back to the basics, saves money for both operators and contractors. The method I use in planning the operations of drilling wells has been refined and detailed over several years.
Options To Increase Drillstring Reliability and Decrease Tool Joint Break-in Cost
Authors: Smith J. E. , Carlin F. J. 
Published: December 2007

ABSTRACT
The API NC type thread form has been available on tool joints and drill collars for about 20 years. It has an advantage over the previously used (and interchangable V.Q65) thread form because it has a full 0.038" (0.97 mm) radius at the thread root.
The full root radius has a much lower stress concentration factor than the flat root and is much easier to cold roll. Both of these attributes give the NC thread form increased fatigue resistance and produce lower stresses when the joint is made up. Development of the NC thread form was a big improvement in drill collar and tool joint threads.
A similar improvement over the NC thread form has recently been developed. This thread form has a 0.057" (1.45 mm) root radius for a further reduction in the stress concentration fac?tor and a change in the pin taper to provide nearly equal loading of the threads along the length of the pin. On NC connections, apporoximately 28% of the total thread load is taken by the last engaged thread and approximately 3% is taken by the first thread. The loads on the last engaged thread and the first thread are about the same on the new connection. The new thread form is interchangable with the NC thread form.
Prebreak-in of tool joints before welding them to pipe can be a big rig cost saving and can provide more trouble free performance when the joints are put into service for the first time.
Measurements While and After Drilling by Multiple Service Companies Through Upper Carboniferous Formations at a Borehole Test Facility, Kay County, Oklahoma
Authors: Hutchinson M. W. 
Published: December 2007

ABSTRACT
Over the past two years five service companies have field tested both their commercial and prototype Measurement While Drilling (MWD) petrophysical sensors in oil base and fresh water base test wells. This paper compares these data to wireline measurements, and also investigates the effect of rate of penetra-tion (ROP) on some MWD devices.A few operational details and some other aspects of the Borehole Test Facility are also discussed.
Predicting Gas Kick Behavior in Oil-Based Drilling Fluids Using a PC-Based Dynamic Wellbore Model
Authors: Van Slyke D. C. , Huang E. T. S. 
Published: December 2007

ABSTRACT
The high solubility of natural gas in oil-based drilling fluids can mask the true nature of a gas kick. The sudden evolution of gas near the surface can lead to severe well control problems. The problem is accentuated to varying degrees by the presence of CO2 or H2S. Previous authors measured gas solubility and swelling behavior of oil-based drilling fluids and natural gases to tune the equation of state (EOS). Multiphase flow and EOS models run on mainframe computers were used to predict the effects of gas kicks on surface indi-cators such as pit gain and annular flow rate while gas kicks were allowed to travel to the surface uncontrolled.
This paper presents a new approach to predicting gas kicks in oil-based drilling fluids utilizing an interactive PC well control model originally developed for water-based drilling fluids. Experi-mental swelling and solubility data were obtained for mixtures of C02-rich gas and "non-toxic" base oil at simulated downhole temperature and pressure conditions. Instead of the EOS, a modular subroutine was written to describe the expansion of these mixtures as a function of pressure, temperature and mixture composition.
The modified model was used to predict pit gain, annular flow rate, casing pressure and gas distribu-tion in the annulus during simulated gas kicks in a hypothetical well. A comparison to water-based drilling fluids under similar conditions was made.
It is concluded that small but potentially dangerous gas kicks in oil-based drilling fluids may not be detected by an early increase in annular flow or pit gain.The dampening of surface response is due to the high gas solubility in the oil phase of the drilling fluid.Stopping circulation to "check for flow" can be used to detect gas kicks in both oil-based and water-based fluids. The well will be flowing in an oil-based drilling fluid because not enough drilling fluid is present deep in the annulus to mask a flow increase. Lower increases in casing pressure, annular flow and pit gain result when circulating a gas kick to the surface under controlled conditions in an oil-based fluid than in a water-based fluid, because all or a portion the gas is forced into solution by the back-pressure that is maintained on the annulus.
Rig Modifications Meet New U.K. High-Pressure Requirements
Authors: Hoopingarner J. B. , Greif C. V. , Neme E. E. , Rodt G. M. , Bates T. R. 
Published: December 2007

ABSTRACT
After an explosion and fire on board a semi-submersible drilling rig in 1988 the UK Department of Energy (D.En.) placed a prohibition on the drilling of high pressure wells until a review of new equipment requirements and procedures could take place. This paper discusses seme of the concerns raised as a result of these investigations and details equipment modifications made to the semi-submersible drilling rig, DRILL STAR, in order to obtain D.En. approval to drill high pressure well 22/29-F. Areas of concern regarding high pressure wells included flexible hoses, BOP elastomers, capacity of mud gas separators, vent lines, well control procedures and training. In conjunction with equipment manufacturers, oil companies, other contractors and the D.En. a coitprehensive review was concluded in each of these areas.
Application of ADAMS (Advanced Drillstring Analysis and Measurement System) and Improved Drilling Performance
Authors: Besaisow A. A. , Ng F. W. , Close D. A. 
Published: December 2007

ABSTRACT
Drillstring vibrations caused by Bottomhole Assembly (BHA) resonances can lead to partial or catastrophic failure of BHA and other drillstring components. Also, maximum bit performance is often not achieved due to drilling parameters that are not optimized. This paper presents case histories where improvements in these areas result from onsite measurement and analysis of dynamic drillstring data using the Advanced Drillstring Analysis and Measurement System (ADAMS).
ADAMS is a surface measurement system comprising an array of strain gauges and accelerometers, which are mounted in a sub above the kelly. Measurements are transmitted by microwave telemetry to a receiving unit on site where the data is demodulated and processed. The unit provides real time visual displays of energy peaks in the drillstring related to hole making and to resonant vibrations. Evaluation of these peaks and adjustment of drilling parameters results in drilling conditions that avoid BHA resonances, produces near optimum bit performance, and extends drillstring life.
Analysis of Transient Foam Flow in 1-D Porous Media with CT
Authors: Liu D. , Castanier L. M. , Brigham W. E. 
Published: December 2007

ABSTRACT
Transient behavior is likely to dominate over most of the duration of a foam injection field project. Due to the lack of experimental data, little is presently known about foam flow transient behavior. Foam flow does not follow established models such as the Buckley-Leverett theory and no general predictive model has been derived. Therefore, experimental data are badly needed. This study investigates transient foam flow in a simple linear porous medium.
Foam is injected at a constant volume rate into a one-dimensional sandpack of 1-inch diameter and 24-inch length, initially saturated with distilled water. The system is placed in a CAT-Scanner. Data are accumulated at low temperature and pressure including the pressure field and saturations obtained by scanning. The liquid saturation can be obtained at each point of a cross section of the pack with less than 1% error over the range of interest. Calculations from the numbers obtained from the scanner show that the best spacial resolution available is a volume element (voxel) of 0.5×0.5×5 mm. Hence a relationship can be found between saturation and pore volume injected for each location in the sandpack. The pressure profiles show that the pressure drop along the sandpack is not evenly distributed and varies with time. The pressure gradient is much greater between the injection end and the foam front than it is ahead of that front. Moreover, the pressure gradient keeps changing as the foam advances in the sandpack. It is this behavior that differs from Buckley-Leverett theory. The cat-scan results demonstrate that the foam displacement is not piston-like. Gas channeling appears near the front, and eventually the foam blocks all these channels. The foam flows through the sandpack, continuously breaking and reforming. It takes two or more pore volumes of foam injection to reach residual liquid saturation.
The saturation versus pore volumes relationships for a given section of the sandpack have been matched with exponential formulas. In general the matches are satisfactory, however the exponents and constants in the formulas vary as a function of the position of the section considered. Graphing the data as saturation versus equivalent pore volumes injected reduces the range of these variations but does not eliminate them. We are unable to explain this behavior to date.
Techniques of measurement of saturations by X-ray CAT-scanning as well as interpretation of CT data will be presented.
The Maximum-Rate Horner Method: An Improved Method of Analysis for Afterflow-Dominated Buildup Tests
Authors: Jones L. G. , Seetharam R. V. 
Published: December 2007

SUMMARY
The Maximum Rate Horner (MRH) method is a new technique to analyze the data from pressure buildup tests with significant afterflow. It can also be used when the buildup period is preceded by sequentially declining variable rates. In this method the pressure is plotted against a modified Horner time, defined using effective flowing (tp) and buildup (Δt) times. Both these times are corrected with a simple function to properly account for the total volume of fluid produced from the formation.
It is shown here that afterflow has a permanent effect on the slope of the Horner straight line if it is neglected. The estimates of permeability (k) and skin (s) are then wrong even if they are based on afterflow-free pressure data. Expressions for these errors in the slope and parameter estimates are presented here. It is also proved that, with its use of corrected values for tp and Δt, the MRH method is not susceptible to such errors. The MRH method also reduces the buildup time required to define the Horner straight line, typically by a factor of two to three.
The empirical parameter a in the van Everdingen-Hurst model for afterflow is shown to have a physical significance in the context of the MRH method. These findings are illustrated using field and simulated buildup tests.
Productivity-Based Service Contracts
Authors: Chambers M. R. , McCready K. E. , Rankin M. D. 
Published: December 2007

Abstract
This paper concerns a cooperative effort between a major producing company and a major service company to establish a business relationship which emphasizes workmanship and productivity instead of traditional unit pricing. The general concepts of and reasons for productivity-based contracts are explored. The viability of these concepts for six common maintenance services are discussed as well as specific results from more than two years of operating experience relating to routine production maintenance (well servicing).
Automated CO2 Injection Control and Well Test Monitoring System
Authors: Claassen M. J. 
Published: December 2007

ABSTRACT
A carbon dioxide flood has been implemented in the Conoco operated Maljamar Cooperative Unit (MCA) which features automated control and monitoring of the injection and well testing facilities. A programmable logic controller (PLC) was used to provide the functionality requirements. The injection system design required the PLC to perform continuous closed-loop control of the CO2 injection well rates and pressures. The well test system design required the PLC to monitor the gas and liquid volumes, control the liquid dump valves, and control the switching of the test header valves. The PLC also functions as a remote terminal unit, transmitting selected information via radio to the host computer for alarm notification, reporting, and database management functions.
This paper describes the instrumentation, PLC system hardware configuration, and programming that was used to perform CO2 injection control and well test monitoring at the MCA CO2 flood.
Effect of H2S on Coatings
Authors: Bouhroum A. , Marx C. , Schade W. 
Published: December 2007

ABSTRACT
Coatings are developed to provide appropriate property response to severe environmental conditions; e. g. heat, stress at temperatures extremes and chemicals.
The influence of hydrogen sulfide on coatings and their protective functions for metal products was investigated in this work.
Six selected primer and one powder topcoat system were applied and exposed to five natural gas mixtures with hydrogen sulfide content of 5%, 10%, 15%, 20%, 25% and 30% to evaluate the chemical and thermal stability of these materials under the follow-operating parameters: –Temperature: 120 °C–Pressure: 15 MPa–Decompression velocity: 6 sec.–Duration of test: 48 h
As a result of exposure to hydrogen sulfide, embrittlement and discoloration of the coating was observed. A series of pigments like TiO2 and Fe2O3 formed sulfates as attacked by hydrogen Sulfide. With an increase in hydrogen sulfide content in gas mixtures, the embrittlement of the coating became more important.
Only one system (CEV-236, PR-8008) among the tested species was found to be chemically and thermally stable.
It is imperative to incorporate hydrogen sulfide scavenging components in coatings to increase chemical stability in sour gas field operations.
Waterflood Pattern Realignment at the McElroy Field: Section 205 Case History
Authors: Lemen M. A. , Burlas T. C. , Roe L. M. 
Published: December 2007

ABSTRACT
A waterflood pattern realignment project in the Grayburg / San Andres McElroy Field is improving the waterflood performance. This paper presents a case history of a 640-acre [259 ha] section of the field that was realigned in 1988. Irregular and widely spaced patterns were developed into smaller and more uniform patterns. The results of the realignment are proving the economic viability of realignment work at McElroy and are improving reservoir characterization.
Reservoir Management: A Synergistic Approach
Authors: Thakur G. C. 
Published: December 2007

ABSTRACT
Because of the complexities and varied areas of expertise involved in making a primary, secondary, or enhanced recovery project successful, it has become necessary to adopt a team approach for reservoir management. Until the early 1970s, reservoir engineering was considered the only item of technical importance in the management of a reservoir. However, after understanding the value of geology, this no longer holds true. The synergism provided by the interaction between geology and reservoir engineering has been quite successful, but the reservoir management has generally failed to recognize the value of other disciplines, e.g. production operations, drilling, and different engineering functions.
This paper provides information on the treatment of reservoir management as a SYSTEM. The System consists of: 1) reservoir characterization, 2) creation and operation of wells, 3) surface processing of the fluids, and 4) fluids and their behavior in the reservoir. These must be considered as interrelated parts of a unified system.
A reservoir management model involving interdisciplinary functions is discussed in this paper. Also, the success of this model in designing and implementing the North Ward Estes CO2 project, Ward/Winkler County, Texas, is discussed in detail. This reservoir management approach has yielded a better design and installation of this CO2 project. In addition, it has resulted in successful workovers, identification of waterflood improvements, and better plans for future CO2 projects.
A team building approach, involving "in-house" reservoir management forums/workshops, has also been employed. The main objective of the workshops has been to facilitate communication among engineering, geology, geophysics, and operations staff. Synergistic recommendations for project improvement have been a mutual outgrowth of these forums.
Horizontal Well Planning—Build Curve Design
Authors: Schuh Frank J. 
Published: December 2007

Abstract
The goal of most horizontal drilling projects is to place a long horizontal hole in a narrow vertical target. To accomplish this objective in the most economical manner, requires a build design that will hit the target without numerous bottom hole assembly changes and a rig that can handle the torque and drag loads produced by the drillstring in the horizontal hole. This paper describes several methods for designing the build curve that offer improved methods for hitting a small horizontal target while using a single bottom hole assembly for the angle building portions of the hole. The paper also presents a novel method for estimating the torque and drag forces for typical drillstrings in a horizontal hole.
Sensitivity to Gridding of Miscible Flood Predictions Made With Upstream Differenced Simulators
Authors: Stalkup F. I. , Lo L. L. , Dean R. H. 
Published: December 2007

Abstract
This paper examines the sensitivity to gridding of first-contact miscible and three-component multicontact miscible condensing-gas drive predictions made with an upstream differenced simulator. These cross-section simulations are made for various reservoir descriptions and for models of increasing numbers of grid blocks. The largest models range from 5000 to 24,000 grid blocks. The paper examines gridding sensitivity when the coefficients of convective terms are evaluated by the single-point upstream method, and it also examines the utility of two-point upstream weighting and selectively refined initial gridding for moderating gridding sensitivity.
These simulations show the following behavior. For some problems with single-point upstream weighting, ultimate recovery changes monotonically with an increasing number of grid blocks. The change in recovery with increasing grid blocks can either be a decrease or an increase depending on the particular reservoir description, although decreasing recovery was the most common behavior for the reservoir descriptions examined here. Two-point upstream weighting and selectively refined initial gridding reduced, but didn't eliminate, this sensitivity. Some predictions appear to converge almost linearly with grid size to approximately the same answer in the limit of zero grid block size (i.e., infinite grid blocks) when the problem is worked in different ways, e.g., single-point weighting, two-point weighting, selectively refined initial gridding. Other problems, however, do not appear to be converging for the largest models that were feasible.
Addition of physical diffusion/dispersion of a magnitude that might occur in reservoirs didn't affect the gridding sensitivity for two of the three reservoir descriptions examined, at least not for grid sizes that were feasible. However, for one reservoir description, recoveries computed with and without physical diffusion/dispersion appear to be diverging with grid refinement.
Effects of Endpoint Saturations and Relative Permeability Models on Predicted Steamflood Performance
Authors: Kumar M. , Do T. N. 
Published: December 2007

ABSTRACT
A comprehensive numerical study was conducted to quantify the effects of endpoint saturations and relative permeabilities on steamflood performance for a heavy oil reservoir. Results show that the region most important for performance prediction is the high-temperature, gas (vapor)-oil relative permeability near the residual oil saturation (Sorg). Furthermore, gas-oil relative permeabilities should be measured at steam temperatures because gas displacement occurs at steam conditions. For the water-oil system, irreducible water saturation (Swir) has a greater effect on performance than residual oil saturation to water (Sorw) and the effect of temperature-dependent endpoint saturations is small.
The linear interpolation model (SPE 17369) for three-phase oil relative permeability is preferable over the Stone's II model because it more accurately predicts residual oil saturation to steam. "Practical" endpoint oil saturations are adequate for performance prediction because very low values of oil relative permeability do not significantly affect recovery calculations. A 15% change in Sorg, Swir, and Sorw resulted in a 26, 13, and 7% change in cumulative oil recovery, respectively.
Reservoir Surveillance Impacts Management of the Judy Creek Hydrocarbon Miscible Flood
Authors: Pritchard D. W. L. , Georgi D. T. , Hemingson P. , Okazawa T. 
Published: December 2007

ABSTRACT
Gravity segregation between water and a hydrocarbon based solvent during miscible flooding has been observed at the Judy Creek Beaverhill Lake (BHD ‘A’ Pool tertiary flood. The solvent override results in bypassing of potential miscible reserves and decreases ultimate oil recovery. An effort to improve overall pool economics through maximizing oil recovery and more efficient solvent utility was sought. A vertical sweep pilot was undertaken to identify optimum pattern sizes by defining the shape and size of the solvent-water comingled region in the reservoir. It was found that the gravity segregation model defined by Stone(1) was representative of the solvent-water comingled zone. A reduction in pattern size was seen to improve tertiary oil recovery levels. This has bolstered a pattern reconfiguration scheme to maximize ultimate oil recovery from the field.
Thermal Stability of Scleroglucan at Realistic Reservoir Conditions
Authors: Kalpakci B. , Jeans Y. T. , Magri N. F. , Padolewski J. P. 
Published: December 2007

Abstract
Thermal stabilities of scleroglucan and two xanthans were determined at 93, 100, and 105°C with and without additives. Aging times varied from 280 to 720 days. The polymers were dissolved in 30,000 ppm TDS seawater with an adjusted pH from 4.5 to 7.5.
Scleroglucan exhibited excellent thermal stability. Under certain test conditions, it lost little or no viscosity at 100°C over 720 days, and only 10 to 20 percent of the original viscosity at 105°C for over 460 days. In contrast to scleroglucan the xanthans were less stable. Depending on the source of the xanthan and the test conditions, viscosity losses varied from 10 to over 90 percent. The triple helix structure of scleroglucan may be responsible for its superior thermal stability.