bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-Pressure Gas Lift for Deep, Sour Production
Authors: Dickens R. J. 
Published: December 2007

Summary
An innovative high-pressure N2 gas-lift design has been used to return several wells to production in the Jay/Little Escambia Creek (LEC) field of northwest Florida. The N2 was available from a field tertiary injection project and provided the means for the first continuous N2 lift system, and some of the deepest gas-lifted wells in operation.
The design accommodates the unique demands of gas-lifting a deep, sour oil well with high water cuts through the operation of a continuous N2 lift system. Because the project design was not limited to conventional artificial lift techniques, a solution was achieved with the resources available. The high-pressure N2 lift enabled wells to return to production that would not have been economically attractive or mechanically feasible with a standard hydrocarbon gas lift or submersible pump design.
Dynamic Performance Testing of Single-Element Unbalanced Gas-Lift Valves
Authors: Winkler H. W. , Camp G. F. 
Published: December 2007

Summary
Reliable predictions of injection gas passage through gas-lift valves are important for unloading and lifting high-capacity wells. This paper outlines the procedure for conducting static and dynamic tests required to evaluate gas-lift valve performance. Limited test results are presented for the 1- and 1½in. [25.4-and 38.1-mm] unbalanced bellows-charged gas-lift valves with three-ply monel bellows.
Effects of Speed Variation on the Performance and Longevity of Electric Submersible Pumps
Authors: Powers Maston L. 
Published: December 2007

Summary
The expanding usage of variable-speed drives (VSD's) indicates that their effects on electrical submersible pump (ESP) performance and longevity merit investigation. This paper demonstrates that speed variation makes ESP equipment selection more complex and critical if maximum pump life is to be achieved. Thrust wear can dramatically affect pump longevity. A common conception is that the rates identifying acceptable thrust limits for any pump speed would be the affinity-law projections of the defining rates at 60 cycles/sec [60 Hz]. This would result in a diverging thrust range as speed increases. This paper (1) shows the fallacy of this concept; (2) demonstrates mathematically and graphically that as speed increases, the thrust range converges; (3) expresses the need for verification of the calculated data with actual measurements; and (4) discusses potential pump damage caused by internal recirculation cavitation at high pumping speeds and the increased exposure’ to vibration damage resulting from speed variation.
The benefits of speed variation are summarized. A specific ESP was selected as a typical pump for illustration. Data were normalized by dividing all characteristics by those occurring at the peak efficiency point. The pump performance data thus obtained are used to illustrate techniques for designing a pump to be driven at variable or nonstandard speeds. An operating window is presented that is bounded by the thrust range limits and by the head-vs.-rate curves that correspond to the maximum and minimum driving frequencies to be considered. This is used in the discussion of VSD applications relative to wells of improving productivity and well testing. Also, the pump/motor mismatch inherent in wide-speed-range applications and resultant low motor efficiency are demonstrated.
Investigations on Viscous Fingering by Linear and Weakly Nonlinear Stability Analysis
Authors: Chikhliwala E. D. , Yortsos Y. C. 
Published: December 2007

SummaryIn this paper we examine the growth of unstable disturbances (viscous fingers) in a water/oil displacement process with a mobile interstitial water saturation. Both linear and weakly nonlinear methods of analysis that include continuously changing mobility and capillary effects are presented. The fingers are assumed to develop as a result of perturbations of a steady displacement.After a brief review of the linear stability results, we implement a weakly nonlinear stability analysis for flow processes near the onset of instability (finite wave-number cutoff). Our numerical results indicate that disturbances near the critical point of the linear theory become stabilized to an equilibrium value, which is a function of the mobility ratio and the capillary number. This behavior suggests supercritical stability, in contrast to the instability predictions of the linear theory.The results of the linear theory are subsequently used to investigate the mechanism of finger growth at the wavelength of the fastest-growing disturbance. Saturation contours and the water flow field are numerically computed as a function of time. The local mechanism for finger growth is shown to be the continuous transfer of water (oil) from oil (water)-rich to water (oil)-rich regions. Although the linear analysis predicts constant increase in the size of the regions, the weakly nonlinear theory shows that fingers eventually stabilize to a configuration of a fixed amplitude. Typical finger growth processes are numerically illustrated.
Mechanical Design Considerations for Fracture-Treating Down Casing Strings
Authors: Clark H. Craig 
Published: December 2007

Summary
This paper deals with the design, handling, and cementing of a casing string that will ultimately encounter a fracture treatment. Various wellhead configurations are suggested that provide safe installations while allowing downhole treating-pressure monitoring and easy flowback operations. Solutions to logistical and operational problems faced with a casing treatment are recommended. A comparison of tubing vs. casing as the fracture-treating medium is also provided to show the substantial cost differences.
Evaluation of Fracturing Results in Deviated Wellbores Through On-Site Measurements
Authors: Kim Chin Man , Champion John H. , Cooper Gary D. 
Published: December 2007

Summary
Four adjacent oil wells in the Kuparuk River oil field, with deviated angles of 6°5′, 24°6′, 27°, and 36°7′ from the vertical at the perforations, were analyzed with prefracturing tests. The total fluid volume for these tests varied from 645 to 840 bbl [103 to 134 m3] of either clean lease oil or water-based fracturing fluid at low to intermediate rates (up to 15 bbl/min [2.4 m3/min]). These wells Were subsequently fractured with proppant-laden fluid. A series of instantaneous shut-in pressures (ISIP's) was obtained for each well. ISIP's and fracturing pressures decreased with time in two of the four wells with a relatively high friction pressure at the end of the pumping. A radially propagating fracture from a point source of pressure explains this decreasing pressure with time. The elasticity theory predicts that a fracture in a deviated, cased wellbore should intersect the wellbore at one location. Only when the deviated wellbore azimuth is near that of the fracture orientation does the fracture sweep the entire perforated zone. This observation of the fracture orientation relative to the wellbore azimuth based on the pressure analysis is enhanced further by postfracture temperature surveys. It appears that only a relatively small volume of proppant could be displaced in a deviated wellbore. The degree of deviation, however, did not appear to be a major concern in the treatment size.
A Model Case History of Infield Drilling and Completion in South Texas
Authors: Barnett K. L. , Jeansonne J. P. , Mitchell R. K. 
Published: December 2007

Summary
This group project presented an opportunity to improve overall operations from title clearance to on-stream producing. Changes and improvements in virtually every area of drilling and completion contributed to substantial savings in time and money. These savings resulted in the drilling of twice as many wells as originally proposed, and all improvements are supported by actual field tests. This paper deals primarily with drilling and completion operations in the Laredo, TX, area.
Evaluation of Devonian Shale Gas Reservoirs
Authors: Vanorsdale Charles R. 
Published: December 2007

Summary
The evaluation of predominantly shale reservoirs presents a problem for engineers traditionally educated either to correct for or to ignore such lithologic zones. Currently accepted evaluation techniques and their applicability are discussed to determine the best way to forecast remaining recoverable gas reserves from the Devonian shales of the Appalachian basin. This study indicates that rate/time decline-curve analysis is the most reliable technique and presents typical decline curves based on production data gathered from 508 shale wells in a three-state study area. The resultant type curves illustrate a dual- (or multiple-) porosity mechanism that violates standard decline-curve analysis guidelines. The results, however, are typical not only for the Devonian shales but for all naturally fractured, multilayered, or similar shale reservoirs.
Well Test Analysis of Data Dominated by Storage and Skin: Non-Newtonian Power-Law Fluids
Authors: Vongvuthipornchai S. , Raghavan Rajagopal 
Published: December 2007

Summary
We examine pressure falloff behavior dominated by storage and skin subsequent to the injection of a non-Newtonian power-law fluid. New solutions to analyze falloff tests are presented in a form suitable for analyzing field data. The effective wellbore concept is used to combine the wellbore storage constant and skin factor. This phase of our work required extensions to the effective wellbore radius concept (for power-law fluids) given in the literature. To improve analysis procedures, we examine the use of the pressure-derivative technique. We discuss the advantages of this method for the problem under consideration.
The Role of the Independent in the U.S. Oil Industry
Authors: Heyser Estill S. 
Published: December 2007

"Independent" Difficult to Define
A precise definition of an "independent" oil producer is difficult because he actually defies description. The usual measurement is that he is a non-major, which then brings up the problem of where "majorhood" sets in on a scale of barrelage, income, degree of integration, etc.
The literature and legend of the industry abound with fabulous stories of a daring, colorful, venturesome breed of American businessman known as the oil independent and wildcatter. A number started enterprises which today are known as major companies.
One of the Society's great patron saints and now elder statesman, John Suman, used to say that when he started out before World War 1, "The mark of a real independent that did a good job was one who had an automobile about a block long, a diamond stick pin, a big bull-dog and a kept woman". Unfortunately, except for a change in some of the status symbols, this type of mythical character still persists in the folklore of our industry and in that of the general public.
One economics professor has said of independents, "The independent, as the non-integrated producer is called, developed into a veritable institution - a typically American phenomenon. The blinding success of the lucky ones hides the tragedy of many losers and large losses".
He said also, "The unique feature of the American petroleum industry is the existence of the thousands of independent producers of crude oil, large and small. These represent a basic element of the industry nowhere except in the United States and in Canada. They not only constitute a unique feature of the petroleum industry in North America but materially affect the position and policies of the large integrated companies. Their mere presence indicates that integration in the petroleum industry of North America is decidedly limited. The more or less complete self-sufficiency in basic raw materials which is typical in other basic mineral industries simply does not exist in the mineral petroleum industry of North America."
A New Algorithm for Estimating Relative Permeabilities From Displacement Experiments
Authors: Kerig P. D. , Watson A. T. 
Published: December 2007

Summary
The process of estimating relative permeability curves from two-phase displacement experiments is considered. A parameter estimation approach overcomes significant limitations of the classic calculation procedure. In this approach, functional representations are chosen for the relative permeability curves. Adjustable coefficients (or parameters) in the functional representations are then chosen to minimize a least-squares objective function. Previous applications of this approach have used exponential functional representations with a single adjustable coefficient (the exponent) for each curve. However, significant errors in the relative permeability estimates may be encountered when this function is used.
It has been determined, in principle, that cubic spline functional representations may be used to obtain accurate estimates of relative permeability curves. The process of obtaining the least-squares estimates for the parameters is more difficult, however, because a significantly greater number of parameters are to be determined. No algorithm has been reported for this purpose. We present an algorithm for estimating relative permeability curves that uses cubic spline functional representations. A unique and essential feature of the algorithm is that it incorporates inequality constraints that ensure that physically realistic relative permeability curves are maintained throughout the iterative minimization process. The performance of the algorithm is demonstrated with data from hypothetical and laboratory coreflood displacement experiments.
Use of Simultaneous Flow-Rate and Pressure Measurements to Replace Isochronal Gas Well Tests
Authors: Horne Roland N. , Kuchuk Fikrl 
Published: December 2007

Summary
The interpretation of gas well pressure-transient tests differs from that of oilwell tests in two important respects: the nonlinearity of the governing equations and the presence of a rate-dependent (non-Darcy) skin. The nonlinearities are commonly avoided by use of pseudofunctions, and the non-Darcy skin effect is handled by use of flow-after-flow, isochronal, or modified isochronal tests. Recent investigations have shown that the simultaneous measurement of well flow rate with well pressure can significantly shorten the test duration required for accurate interpretation. These methods rely on use of the straight-line approach, however, and in some cases on trial and error. This paper describes a computer-automated interpretation approach that can be applied generally for any type curve without trial and error. The use of this interpretation technique can reduce the test duration to only that required for a standard drawdown or buildup test, and will allow the estimation of the stabilized deliverability potential without flowing the well until stabilization is reached. Examples of use of the method on both simulated and real data demonstrate its effectiveness.
Fracture Geometry and Proppant-Transport Computation for Multiple-Fluid Treatment
Authors: Lee W. S. , Daneshy A. A. 
Published: December 2007

SummaryThis paper incorporates expressions for changing the flow-behavior index, n′, and the flow-consistency index, K′, of fracturing fluids used in any treatment into a dynamic procedure for fracture design to determine simultaneously the temperature profile, viscosity profile, location of each fluid, and location of each proppant in the fracture, together with the resulting geometry. After pumping ceases, the effect of temperature recovery on proppant deposition and fracture closure is also considered.Several examples demonstrate the effective use of this new procedure for better fracture design. These examples will show the effect of temperature on fluid behavior and its influence on proppant deposition in the fracture.
A Thermodynamic Correlation for the Minimum Miscibility Pressure in CO2 Flooding of Petroleum Reservoirs
Authors: Enick Robert M. , Holder Gerald D. , Morsi Badie I. 
Published: December 2007

Summary
A graphic equation-of-state (EOS)-generated correlation for the minimum miscibility pressure (MMP) of CO2/crude-oil displacements is presented, along with a brief review of 17 other MMP correlations.
The MMP is estimated as the cricondenbar or first-contact miscibility pressure of the pure or impure CO2/crude-oil system in which the C5+ oil fraction is modeled as a single normal alkane of equivalent molecular weight. The correlation accounts for all the experimentally observed trends in MMP in a consistent manner and is independent of any CO2/crude-oil data base. A correction is introduced, however, to prevent a predicted increase in the MMP with decreasing temperature at low temperatures for high-molecular-weight oils. The average predicted-MMP/experimental-MMP ratio for 157 CO2/crude-oil MMP values is 1.09, with a standard deviation of 0.19. Unlike other correlations, specifically those relating MMP with CO2 density, a decrease in MMP with temperature at elevated temperatures (&gt; 120°C [&gt; 248°F]) is predicted.
An Overview of Gravel-Packed Completions
Authors: Heng H. B. 
Published: December 2007

Summary
Sarawak Shell Bhd./Sabah Shell Petroleum Co. (SSB/SSPC) experience with gravel-packed completions covers some 12 years. During that period, some 290 gravel-packed zones have been completed, and about 400×106 bbl [64×106 m3] of oil have been produced through gravel packs in 13 offshore fields.
This paper presents an overview of the development of gravel-packing methods, with special reference to the new gravel-packing technique developed in early 1984 for the Bay an field gravel-packed completions. Productivity reduction resulting from gravel packing and the long-term performance of the packs are discussed briefly.
Depositional Systems and Diagenesis of Travis Peak Tight Gas Sandstone Reservoirs, Sabine Uplift Area, Texas
Authors: Fracasso Michael A. , Dutton Shirley R. , Finley Robert J. 
Published: December 2007

Summary
The Travis Peak formation (Lower Cretaceous) in the eastern East Texas basin is a fluvio-deltaic depositional system divided into large-scale facies packages: a middle sandstone-rich fluvial and delta-plain sequence that is gradationally overlain and underlain by a marine-influenced delta-fringe zone with a higher mudstone content. Domes and structural terraces on the west flank of the Sabine Uplift influenced deposition of Travis Peak sediments, and most Travis Peak gas production in this area is from thin sandstones (&lt;25 ft [&lt; 7.6 m] thick) in the upper delta-fringe facies. The trapping mechanism is stratigraphic pinch-out of sandstones or porosity zones within sandstones, or both, on the flanks of structures.
Detailed mapping of producing sandstone sequences in the uppermost upper delta-fringe on the western flank of the Bethany structure has delineated fluvial channelways, distributary or tidal channels, and barrier or distributary-mouth bars. Most Travis Peak gas production in the Bethany West area is from the bases of channel sandstones in a marine-influenced facies belt.
Travis Peak sandstones in the eastern East Texas basin have undergone a complex series of diagenetic modifications. Precipitation of authigenic quartz, ankerite, dolomite, illite, and chlorite and the introduction of reservoir bitumen were the most important causes of occlusion of primary porosity and reduction of permeability. Permeability decreases with depth in the Travis Peak, which suggests that the diagenetic processes that caused extensive cementation and resultant low permeability throughout most of the formation operated less completely on sediments deposited near the top of the succession.
Viscosity Measurements in the Presence of Wall Slip in Capillary, Couette, And Parallei-Disk Geometries
Authors: Yoshlmura Ann S. , Prud'homme Robert K. 
Published: December 2007

Summary
Measurements of viscosities for slurries, cements, gels, foams, and emulsions are often confounded by the presence of slip at solid boundaries. Slip arises from thin regions of low-viscosity fluid at the boundary that result in large velocity gradients near the solid surface. Unless the measurements are corrected for slip, the calculated viscosities will be smaller than the true fluid viscosities. We review available techniques for determining wall slip velocities and viscosities in standard geometries. The earlier techniques of Mooney for capillaries and Couette geometries are presented. In addition, new analyses are presented for Couette and parallel-disk geometries. The new Couette analysis requires only two measurements rather than the three required in Mooney's analysis. Examples showing the application of these techniques are given for the capillary, Couette, and parallel-plate geometries. Experimental techniques to eliminate wall slip by use of rough surfaces are described.
Laboratory Study of Lost Circulation Materials for Use in Both Oil-Based and Water-Based Drilling Muds
Authors: Nayberg T. M. 
Published: December 2007

Summary
Lost circulation is one of the most troublesome and costly problems encountered in drilling. This problem is magnified when expensive oil-based muds are used. There are many lost circulation materials (LCM's) that perform effectively in water-based muds but very few that work well in oil-based muds. Those that do work well are effective in controlling seepage loss only.
This paper presents laboratory test results that compare the performance of conventional LCM's with a new high-performance material, composed of thermoset rubber, in controlling mud loss to simulated fractured formations in both oil- and water-based muds. Field case histories describe the effectiveness of the thermoset rubber in fractured formations with severe lost circulation problems.
Analysis of Helical Buckling
Authors: Kwon Young W. 
Published: December 2007

Summary
A new solution to helical buckling is presented yielding real helical shapes of buckled pipes with a varying helix pitch. This solution has been developed with the beam/column equation. The change in length and the bending stress can be computed from the helical-buckling solution. In addition, a new equation for tool clearance in helically buckled pipes is provided.
Openhole Packer for High-Temperature Service in a 500°F Precambrian Wellbore
Authors: Dreesen Donald S. , Miller James R. , Halbardier Floyd A. , Nicholson Robert W. 
Published: December 2007

Summary
An openhole packer system has been designed, fabricated, and tested. The system has been used to isolate zones, to conduct injection tests, and to stimulate a 500°F [260°C] hot dry rock (HDR) geothermal reservoir. After exposure to temperatures of 460°F [238°C], the packer has functioned at differential pressures up to 5,500 psi [38 MPa]. Three high-pressure, massive hydraulic fracturing operations, each injecting more than 1 million gal [3800 m3] of water, have been conducted with the packer system.
Design Considerations for an Inhibitive, Stable Water-Based Mud System
Authors: Chesser B. G. 
Published: December 2007

Summary
This paper discusses the technique of using high-molecular-weight organic polymers to stabilize troublesome shales through the adsorption of a protective polymer layer. It specifically covers the performance of a partially hydrolyzed Polyacrylamide (PHPA) in respect to shale preservation and in the retardation of cuttings dispersion. Other design factors—e.g., pH control, rheological stability, and lubricity—are also covered.