bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applications of a BHA Analysis Program in Directional Drilling
Authors: Rafie S. , Ho H.-S. , Chandra U. 
Published: December 2007

Abstract
The application of a three-dimensional directional drilling computer program, named DIDRIL*, is discussed. It is used to analyze building, dropping, and holding assemblies in straight, 2-D curved, and 3-D curved (spiral) boreholes. The effects of WOB, TOB, and borehole curvature on the build/drop and walk trends of the assemblies are studied. The results show that the curvature of the borehole has strong influence on the build/drop and walk tendencies of BHAs, whereas the TOB has little effect.
A Contractor's View of Drillpipe Life
Authors: Gensmer R. P. 
Published: December 2007

ABSTRACT
The single highest unplanned expense on a drilling rig is the loss of drill pipe. Yet, virtually no published data are available on the life expectancy of a drill string. The majority of information on the type of failures discusses tool joint damage, a condition which accounts for only 3.67% of our losses. In response to this apparent void, we offer to share a unique data base of almost 1,300 pipe failures from 30 strings which were used in the Williston basin of North Dakota/Montana over the last 14 years. These strings were kept together as identifiable units for their useful life, were subjected to approximately the same drilling conditions, and thus, offer us field laboratory conditions.
Concentrating on the most numerous and costly pipe loss factors--tube holes/cracks--we will present an average pipe life curve with a 65% confidence envelope. This curve can be used in estimating the cost of running pipe and planning a replacement schedule. By implementing failure containment strategies, we showed a 50% increase in pipe life. However, as competitive pressures of the current market have resulted in increased operational stresses, we can see a regression in pipe life expectancy.
As the basis for working out solutions to this change, we will look at where the tube failures occur in relationship to location in the individual tube, location in the string, and depth in the well. The results give us symptoms of string failure which contradict some widely held beliefs such as: the tube losses occur chiefly in either the slip or weld areas.
Computer Control of Minimum Shoulder Prestress Requirements During Makeup Procedure of Premium Shoulder Connections
Authors: Marojevic S. T. 
Published: December 2007

ABSTRACT
The new proposed method and computer control technique of optimal shoulder prestess value during make-up procedure of (premium) shouldered connections assures uniform stress control and optimizes utilization of tubular goods with schouldered type connections. Application of minimum shoulder prestess requirement with regard to the threshold stress-level provide the highest safety and the most efficient use of tubular goods in a corrosive environment. During make-up procedure this method helps to overcome the influence of different parameters such as: machining tolerances, dope and plating qualities with their corresponding friction losses etc; which otherwise might jeopardize connection mechanical and sealing integrity.
Gravel Packing Operations from a Floating Vessel
Authors: Zaleski T. E. , Donovan J. F. 
Published: December 2007

ABSTRACT
Standard gravel packing equipment requires precise manipulation of downhole tools to direct fluid flow as desired. Floating vessels present a particular problem because the tools are generally positioned with the workstring in full tension suspended by the elevators. Without a stationary rotary table from which to measure, finding and holding each position becomes impossible when wave heights exceed a few feet. A specially designed set of gravel packing tools has been developed that allows accurate downhole positioning from all types of floating vessels.
Deep Wildcats: New Challenges to Pipe and Connection Manufacturers
Authors: van Cuyck G. H. , Dlaska H. C. 
Published: December 2007

Abstract
Several deep wildcats, spudded in 1984 and 1985, were drilled or are still drilling in extremely hostile environments with total depths of more than 20,000 feet. Special tubulars and connections had to be specified, manufactured and tested to reach TD with an 8-1/2″ bit size safely. Mannesmann was present with the pipe and connection technology from the initial planning stages through running of the fallowing long and heavy strings: OnshoreWeight in Air12,455 ft. 20″169#C-95Big Omega2.2 Mio.#13,970 ft. 16″146#P-110BDS-52.2 Mio.#16,695 ft. 14″106#C-110BD5-51.9 Mio.#Offshore4,919 ft. 26″266#X-56SML51.4 Mio.#11,852 ft. 18-5/8″178#C-95Big Omega2.2 Mio.#15,820 ft. 14″120#C-110HPC1.9 Mio.#20,000 ft. 10-3/4″96#C-100/P-110HPCdelivered/not run yet
Some of the measures which were taken to improve and assure product quality and performance in order to satisfy all load and environmental requirements will be discussed in this paper.
Control of Annular Gas Flow in the Deep Anadarko Basin
Authors: Matthews S. M. , Copeland J. C. 
Published: December 2007

Abstract
Gas channeling often occurs soon after the placement of a conventional cement slurry in wells having gas. The slurry, during and immediately after placement, will act as a true fluid transmitting hydrostatic pressure onto the gas-bearing formation, until the cement begins to gel or set. As long as the hydrostatic pressure remains above the gas formation pressure, no gas will penetrate the cement column. However, as the cement begins to set (changing from a fluid to a rigid material), it gradually loses its ability to transmit hydrostatic pressure. This process is often called the "transition period." Shrinkage compounds the problem, leading to poor bonding between the cement and formation, thereby allowing gas to flow at the interface.
A field study has been conducted on a design approach which incorporates a unique cement slurry which interacts with incoming gas to form an impermeable barrier in the cement pore spaces, thereby inhibiting further gas flow.
Seventy-seven wells in Oklahoma and the Texas Panhandle using this cement slurry were reviewed. Based on success being defined as no gas migration to surface or no indication of interzonal communication, 86% of these wells were classified as successful.
Case histories of five wells giving qualitative and well parameters used in the design are discussed, along with results.
Perforation Breakdown Improves Permian Basin Stimulation Results
Authors: Scott T. A. 
Published: December 2007

ABSTRACT
Permian Basin operators have recently achieved improved stimulation results using precision perforation breakdown prior to their stimulation treatments. Precision breakdown of individual perforations is made possible by a recently developed hook wall straddle packer that isolates intervals of casing as short as 3 in.
In previously used procedures, ball sealers, temporary blocking agents and high fluid injection rates were used to break down perforations. These methods were partially successful, but in some cases were detrimental to the stimulation and well performance due primarily to the fact that the operator did not know the status of the perforations at the time of the major stimulation.
The precision perforation breakdown method uses minimal pressure and pumping rate to help prevent fracturing into unwanted gas or water, and gives a positive indication that each perforation is broken down and will accept fluid. Values such as (1) instantaneous shut-in pressure and (2) perforation breakdown pressure can be obtained for individual perforations. This data is useful for designing the stimulation job and for design of subsequent jobs to be performed in the same field.
Subject paper discusses the conditions and circumstances under which precision perforation breakdown may be used to good advantage. Actual job logs and tool schematics illustrate the use of the precision breakdown method.
Determination of Formation Water Resistivity Using Shale Properties
Authors: Dusenbery R. A. , Osoba J. S. 
Published: December 2007

ABSTRACT
A new method is presented to determine formation water resistivity (Rw) in sandstones. This procedure does not use the Spontaneous Potential (SP) log. Instead formation Rw is obtained from the overlying shale zones.
To understand the correlation between shale and sandstone waters, consider that during deposition their salinities are approximately equal. After compaction the waters in both shales and sandstones are in equilibrium. Because shales are impervious to drilling fluids a true value of water resistivity and salinity in the shale can be obtained from Archie's equations. The formation water resistivity is determined from the shale salinity and a relationship developed from core data.
The shale method is simple to use requiring only the shale resistivity and porosity. This makes it ideal for field use. It also is accurate for both normal and geopressured wells.
The presented technique is compared to other interpretation methods on several wells. The results compared well with other data.
A Complete Integrated Model for Design and Real-Time Analysis of Hydraulic Fracturing Operations
Authors: Crockett A. R. , Okusu N. M. , Cleary M. P. 
Published: December 2007

Abstract
A new comprehensive model of hydraulic fracturing is presented which has been developed for the Gas Research Institute (GRI) mobile fracture monitoring and analysis facility. The main purpose of the model is to simulate the hydraulic fracturing process in real-time, that is on-site during the fracturing operation, but the model can also be used for pre-fracture design and post-fracture analysis. Sensor data obtained during the course of the job — such as wellhead pressure, flow rates, frac-fluid viscosity, and proppant staging — can be received directly by the model as input, superceding the pre-frac job design schedule, and making possible more accurate model estimates of current fracturing conditions and predictions of final fracture geometry, as the job proceeds.
The overall model has four major components describing:
— flow of fluids and slurry in tubular goods — creation and propagation of the hydraulic fracture — transport of proppant, deposition, and fracture closure — heat and fluid exchange between fracture and reservoir.
This fully-integrated, numerically robust model of the hydraulic fracturing process takes directly into account as much of the essential physics as possible, given the computational limitations of the real-time application. Additional information, pertaining to very complex reservoir characteristics, can be indirectly supplied to the model through data-based results obtained prior to the job from other more comprehensive (e.g., 3D, cross-sectional) fracture simulations. Having thereby embedded more elaborate fracture analysis into a simple lumped model, accurate predictions are achieved at execution speeds faster than real-time, allowing on-the-job analysis and even real-time history matching for unknown reservoir parameters.
Sample results are presented from model simulations of a fracture treatment performed in the Travis Peak formation of East Texas. Actual sensor data from the job was used as input and model predictions are compared with field measurements.
A Continuous Mixture Computational Algorithm for Reservoir Fluids Phase Behavior
Authors: Du P. -C. , Mansoori G. A. 
Published: December 2007

ABSTRACT
Development of compositional reservoir simulators is presently hampered due to the complexity of the existing computational algorithms of reservoir fluid phase behavior calculations. Through the application of the theory of polydisperse fluid mixtures we have developed a new algorithm for reservoir fluid phase behavior calculations. In this algorithm a reservoir fluid is considered to consist of a continuous mixture with a defined molecular weight/composition distribution. The proposed algorithm requires less computational time than the time required by the existing pseudocomponent VLE calculation methods. It is also shown that the new algorithm is applicable to varieties of equations of state and mixing rules. Results of the proposed technique are compared with results of the other existing techniques, and with the simulated multi-pseudocomponent reservoir fluid mixture data.
Stabilization of Naturally Flowing Oil Wells Using Feedback Control
Authors: Blick E. F. , Boone L. 
Published: December 2007

ABSTRACT
Some naturally flowing oil wells will experience flow instabilities (heading) characterized by regular or irregular cyclic variations in tubing pressure and flow rate. In order to analyze this phenomena, the unsteady equations of motion for flow out of the reservoir, flow out of the annulus and flow up the tubing are derived and then solved by the LaPlace Transform method. This analysis produces a characteristic equation whose coefficients allow one to determine if a particular well is stable or unstable. If the well is unstable it is possible to use a feedback controller which varies the tubing head choke diameter to stabilize the well. Various combinations of proportional, derivative and integral controllers are shown to theoretically control some unstable wells.
In-Situ Heat and Paraffin Inhibitor Combination Prove Cost Effective in NPR #3, Casper, Wyoming
Authors: McSpadden H. W. , Tyler M. L. , Velasco T. T. 
Published: December 2007

ABSTRACT
Recent application of an in-situ heat and nitrogen generating system has led to a cost effective method of paraffin control for the Department of Energy at the Naval Petroleum Reserve (NPR) #3 in Casper, Wyoming. The combination of in-situ heat, solvent and paraffin inhibitor has not only prolonged productivity but also effectively stimulated the producing zones.
This paper describes paraffin treatments with the in-situ heat generating system in the NPR #3. Case histories showing candidate selection, pre and post treatment production levels and economics are presented.
Testing and Evaluation of an Arctic Fractured Carbonate: The Lisburne Formation, Prudhoe Bay
Authors: Fisher D. W. , Clutterbuck P. R. 
Published: December 2007

ABSTRACT
The Lisburne Group is a Pennsylvanian-Missisippian age carbonate sequence which underlies the main Permo-Triassic producing horizon at Prudhoe Bay. During the last three years, delineation and appraisal efforts have accelerated leading to financial commitment to field development. Production startup is scheduled for December 1986.
This paper discusses the details of well planning and implementation necessary for the evaluation of this complex, fractured, low permeability limestone and dolomite reservoir. Well operations and testing have included techniques previously uncommon or unused in the Alaskan Arctic such as lightweight mud and cement, bland and pressure coring, open-hole tests with open-hole solvent stimulations, nitrified acid treatments, nitrogen lift of cased hole tests and fracture treatments. These methods helped ensure conclusive tests in a formation that is characteristically difficult to test and also established procedures to affect commercial well completions.
Methods used in the analysis of well results are also discussed briefly to provide some insight into the use of the well data in the overall evaluation process.
A New Method for Automated History Matching of Reservoir Simulators
Authors: Dye L. W. , Horne R. N. , Aziz K. 
Published: December 2007

ABSTRACT
This paper presents a new approach to automated history matching. Instead of the usual, "mathematically-oriented" approach in which the strongly non-linear reservoir responses are locally linearized, this paper describes a "reservoir engineering-oriented" approach which attempts instead to use a combination of reservoir responses that is truly linear.
Two accurate linear models of a numerical reservoir simulator's pressure and production response to permeability changes are presented. These models, which are derived from the general hyperbolic decline curve relationship, are used in a history matching scheme to estimate the permeability distribution from historical production and pressure information. Three cases are presented which test the methods presented in matching for isotropic and anisotropic permeability distributions. The cases are based upon history generated from a 72 block 7 well model, and include both anisotropic and isotropic history matching problems.
A method of simultaneous determination of absolute and relative permeabilities is. also presented. The method is based upon the isotropic linear permeability model developed and tested in the paper.
The history matching technique presented requires only two or three simulation experiments to accomplish the match. This is approximately one-tenth the CPU cost required for the optimal control theory automatic history matching methods described in the literature.
A Study of Multiphase Flow Behavior in Vertical Oil Wells: Part II—Field Application
Authors: Kabir C. S. , Hasan A. R. 
Published: December 2007

ABSTRACTIn the second part of the paper, we show the application of a vertical multiphase flow model, developed from first principles. Estimation of gas void fraction, or mixture density – leading to pressure gradient estimates in each flow regime, and transition from one flow regime to another are modeled rigorously. An appropriate model is also used to handle flow in a tubingcasing annulus. Parameters, such as, tubing to casing-diameter ratio and the equivalent diameter of the flow channel, developed from our experimental work, are incorporated in the model. Thus the model is capable of handling flow in both circular and annular channels.Standard oilfield correlations are used for estimating PVT properties of oil and gas: Standing's correlation for solution gas-oil ratio; Katz's correlation for oil formation volume factor; Standing's, and Chew and Connally's correlations for dead and live oil viscosities, respectively; and Lee et al.'s correlation for gas viscosity.Computation on test data gathered from some 115 oil wells, involving all the two-phase flow regimes, indicates that the proposed model performs better than the other models considered: Aziz et al., Orkiszewski, Duns and Ros, Beggs and Brill, Hagedorn and Brown, and Chierici et al. Calculations also reveal that bubbly and slug flow are the dominant flow mechanisms in most cases, while churn and annular flow are associated with high flow rate wells.Hydrostatic head contributes to the most of the pressure drop (90 % +) when the flow is essentially restricted to the bubbly and slug flow. However, the frictional head becomes significant in annular flow. The test data bank used in this study is that previously used by other authors; thus, validation of the proposed model is made with an independent data set.
Rediscovering an Abandoned Reservoir: The Lakota Formation at Lost Soldier Field, Sweetwater County, Wyoming
Authors: Schmechel D. J. , McGuire M. J. 
Published: December 2007

ABSTRACT
The Lakota reservoir at Lost Soldier Field was discovered in 1922. The Lakota produced about 5 MMBO between 1922 and the early 1950's, when the reservoir was abandoned. Since 1979 32 wells have been completed or recompleted in the Lakota formation. These wells should produce about 1 MMBO. The rediscovery of the Lakota reservoir at Lost Soldier Field points out a wide opportunity--to reenter abandoned reservoirs and develop overlooked reserves.
In-Situ Stresses: A Comparison Between Log-Derived Values and Actual Field-Measured Values in the Travis Peak Formation of East Texas
Authors: Whitehead W. S. , Hunt E. R. , Finley R. J. , Holditch S. A. 
Published: December 2007

ABSTRACT
Knowledge of in-situ stress distribution within reservoir sandstones and the surrounding formations is recognized as one of the most important factors in the design and analysis of hydraulic fractures. Stress contrast between various layers of rock ultimately controls the vertical fracture growth and, thus, directly affects fracture length and width. Even though the importance of stress distribution is evident, these data are rarely measured due to the associated expense, interpretation problems and mechanical risks.
Currently, there are log analysis techniques available which can provide calculated values for mechanical properties and in-situ stresses. These techniques are based on classic theories of elastic stress-strain relationships and appear to be reliable in tectonically relaxed areas. In geologically active areas, however, external horizontal stresses may be present which cannot be calculated by these static techniques. In such formations, empirical field corrections must be included to accurately determine the in-situ stresses.
This paper summarizes the results from a study where actual field-measured values of in-situ stress have been compared to log-derived values. The study was conducted on wells completed in the Travis Peak (Hosston) formation of east Texas. A discussion of the regional geology is presented which describes how fluvial-deltaic depositional patterns and local facies variations control the sandstone geometry and distribution of possible fracture barriers.
In-situ stresses within sandstones, siltstones and shales were actually measured on three wells. Empirical corrections to the log-derived values were necessary in order to fit the measured data. The resulting correlations between log-derived values of stress and field-measured values of stress should be of benefit to the industry. The ultimate goal for all concerned with the problem is to learn how to reliably evaluate stress distribution from logs for fracture treatment design purposes.
A Method for General Reservoir Behavior Simulation on Digital Computers
Authors: Sheldon J.W. , Harris C.D. , Bavly D. 
Published: December 2007

Abstract
A large-scale computer method for reservoir simulation in two dimensions is described. The physical effects taken into account are gravity component parallel to bedding plane, solubility and compressibility for two flowing phases, which may be oil and water or oil and free gas. Fluid flow is treated optionally as either homogeneous or segregated. A new numerical method for treating gravity in the two-phase flow equations is presented. The member to be simulated is described in terms of cells. A material balance is obtained for each cell. The cells may be chosen of variable size so that small cells can be used in the oil-bearing regions and large cells in the aquifer. A data-handling system to facilitate problem preparation and display of results is described. Applications of the simulator, particularly to the Arab-D member of Saudi Arabia, are discussed.

Introduction

Reservoir Behavior Simulation
We define reservoir behavior simulation to be the response of an analogous model to disturbances corresponding to fluid withdrawals and infections. The model we call the reservoir simulator. In this paper, our main interest is to describe a particular reservoir behavior simulator. We also describe an example of production member behavior. However, this is only for illustration. Our main interest is the simulator itself.

A Discussion of Reported Methods of Simulation
Reports of reservoir behavior simulation appear frequently in the Journal of Petroleum Technology. The incentive for all this work is economic. The engineer believes he can plan more efficiently development of a reservoir when its behavior can be simulated.
Probably the earliest attempts at simulation are characterized by the term "case histories". Here, the investigators report the behaviors of reservoirs together with a description of the reservoirs. These reports are of interest to other persons if they have a similar reservoir at hand.
The first quantitative simulation of reservoir behavior seems to have been gained by omitting all consideration for spatial behavior. Only the principles of thermodynamics (temperature-pressure-volume relations) and conservation of matter are employed. No flaw dynamics are simulated. This model is now called the "Schilthuis" equations.