bluuebunny/crossref_metadata_2025 huggingface dataset:
Inflow Performance Relationship For Perforated Wells Producing From Solution Gas Drive Reservoir
Authors: Sukarno Pudjo , Tobing Edward L.
Published: December 2007

The IPR curve equations, which are available today, are developed for an open hole wells. In the application of Nodal System Analysis in perforatedwells, an accurate calculation of pressure loss in the perforation is very important. Nowadays, the equation which is widely used is Blount, Jones and Glaze equation, to estimate pressure loss across perforation. This equation is derived for single phase flow, either oil or gas, therefore it is not suitable for two-phase production wells. In this paper, an IPR curve equation for perforated wells, producing from solution gas drive reservoir, is introduced. The equation has been developed using two phase single well simulator combine to two phase flow in perforation equation, derived by Perez & KeIkar. A wide ranges of reservoir rock and fluid properties and perforation geometry are used to developed the equation statistically.

Introduction

In the application of Nodal System Analysis, perforation is an important component in a well production system. Different perforation technique, different perforation length and diameter yield different well productivity and at the end of the analysis yield different cost and revenue. Therefore, optimization is needed to choose the "right" perforation technique and geometry. In Nodal System Analysis, a good equation of flow performance inperforation, is needed. An equation that suitable to the well conditions. Blount, Jones and Glaze had derived an equation to predict flow performance inperforation for single phase flow (gas or oil). Therefore, the equations are not applicable for wells producing gas and oil (two-phase wells), such like a well producing from solution gas drive reservoir. Perez & Kelkar had derived an equation to predict two-phase pressure drop across perforations. In the application, this equation need information of oil relative permeability atcrushed zone, as well as number of perforations, perforation size and length, viscosity and formation volume factor of oil, pressure at crushed zone and pressure at perforation. Therefore, for practical purposes, Perez & Kelkar equation should be combined with other method which gives the value of oil relative permeability, and the pressure at crushed zone and perforation. In this paper, a two-phase single well simulator is used to prepare the oil relative permeability data, at certain production conditions. The well productivity performance usually is represented by Inflow Performance Relationship (IPR) equation. All of those equations, which are available today, do not consider the effect of perforation. In this paper an IPR equation, which is consider the effect of perforation technique and perforation geometry, is proposed.

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Ecuador Strategic Alliance Project: A Case History
Authors: Peery M. D. , Thomson C. L.
Published: December 2007

The alliance contract is a new project management approach that can obtain improved contractor performance on large drilling, completion and production projects. Under the arrangement known as the Ecuador Strategic Alliance, Oryx Ecuador Energy Company entered into a single contract with Baker Hughes INTEQ, an integrated service company, which assumed many duties previously handled by the operator. Services covered 15 wells in Block 7, located in the Oriente region, Ecuador. (See Figure 1) Included in the contract as alliance partners were several other service companies. This management approach is believed to be unique in the industry in that the alliance of competitive companies agrees by contract to manage and execute the entire program, making decisions that will benefit the program without regard to the source of products and services. No dedicated operator representative is resident at the site. In this approach partners in the alliance must manage to achieve best results in order to receive incentives upon successful completion of contractual milestones. The paper reviews salient points of the alliance working arrangement, covering responsibilities of the various service companies and management methods used in the successful achievement of program objectives. Operational and economic results of the arrangement are described over a period of operation in which the first 13 wells were completed.
Organisation, Integrity, Learning—The Keys to Success in Well Construction
Authors: Thorogood J. L.
Published: December 2007

New contracting styleshave placed increased demands on service companies, contractors and operators alike. As the service sector professes a willingness to "take on more responsibility", so operators are faced with the challenge of taking up this offer. With responsibility goes risk, but the burden of risk must be rewarded.

Do service companies really want more responsibility, and thus, accountability or merely to be "involved" in a diffuse, multi-disciplinary way? If, indeed they want to take responsibility then, before it can be transferred, and the discussions on risk and reward begun, the question to be asked is, "If I give my contractor responsibility, will he let me down? Am I running an unjustifiable risk? What will happen to my reputation if something goes wrong?" In a traditional oilfield, responsibility could be transferred quite informally by relying on the fruits of personal relationships and trust. But in the contemporary oilfield, with large organisations and impersonal quality systems, a risk-free transfer is less easily achieved.

Cost reduction is the main driver behind these changes. Cost reduction without technical integrity will create serious risks. Responsibility is transferred by getting the operator and contractor to work together in a logical and structured way. The end result is a relationship where the operator can confidently delegate work to a contractor that has demonstrated his capabilities. A model is presented that provides a check-list for five aspects of a contractor's work: his organisation, logistics and his capability to design, execute and continuously improve his performance. This new role will require structural changes inside the service companies, development of a culture of Technical Integrity and development of the habits of Performance Measurement and Continuous Improvement.
Steps Towards a Comprehensive Reeled Tube Drilling System
Authors: Faure A. M. , Oosterling Peter , Lord D. J. , Vuuinghs Pieter , Brinkhorst Jan
Published: December 2007

The oil industry is facing the challenges of reduced margins with respect to optimization of mature field and development of marginal discoveries. In this context conventional approaches are reaching their limits and a step change is required.

The first oilwells were drilled using the cable tool method. The Rotary drilling revolution was introduced in 1901 and became firmly established in 1920. Since then the industry has been dominated by the reign of the 30 ft. joint. Replacing jointed pipes by continuous reeled tubes could indeed become the next step change. A visionary Reeled System (RS), including drilling umbilicals, casing, tubing and pipelines could improve the economics of hydrocarbon development projects. RS could reduce costs, enhance quality, broaden technical abilities and improve well productivity.

An all around RS does not exist and the intention is not to build one from scratch. However, Coiled Tubing (CT) is presently the nearest thing to the reeled tube vision. Recent experience prove CT can be used for drilling, completions and flowlines and its envelope of application is rapidly expanding.

It is proposed to build a global alternative to jointed pipes by gradually improving the technical abilities of the existing CT system. Pieces of the giant jigsaw puzzle are already in place. Others are still at the conceptual stage while some are still barely visible. Reeled System Technology (RST) will evolve at its own pace driven by market forces, technology innovation and most importantly attitude change. Rather than a mere technical improvement this technology authorizes new strategies for hydrocarbon exploitation.
Drilling Performance Predictions: Case Studies Illustrating the Use of Risk Analysis
Authors: Peterson S. K. , Murtha J. A. , Roberts R. W.
Published: December 2007

This paper presents two predictive drilling performance models, using two dissimilar case studies to illustrate some of the appropriate techniques for developing such models. Both case study models utilize risk analysis and incorporate Monte Carlo simulation and statistical analysis of historical drilling data to generate more representative, risked, AFE estimates. The first model was developed for a development well in a mature area. The second case study, for a rank wildcat, incorporates limited "nearby" well data and historical data pertaining to analogous exploration wells, and demonstrates the usefulness of a large database from which we can draw representative distributions.
Results Oriented Strategies in Well Engineering Operations
Authors: Jackson J. R. , Avocato N. S.
Published: December 2007

Chevron UK Limited (CUK) implemented a performance driven strategy commencing in 1991 based upon core alliance agreements enabled by metrics, benchmarking, and operational scanning to optimize well engineering and operations (WEO), all organized around a set of core processes. This strategy was initiated in response to new field developments, continued operations in mature fields, and the maturing of the North Sea as a producing area with emphasis on performance and cost management. It was implemented over a period of four years for the core competencies of WEO including well construction (WC) (drilling) and well management (WM) (workovers). The results of this strategy will be reviewed.
Deep, Directional Platform Drilling: Problems and Solutions
Authors: Wallen G. L. , Striedel C. M.
Published: December 2007

Attention to detail and the utilization of operational techniques that have been around since the 1960's and 1970's have resulted in the drilling of directional platform wells over 18,000 feet deep, with 40-45 degrees of angle, in just 23 days from spud. Although this paper discusses deep, platform drilling, the techniques are basic and they have a broader utility to a range of drilling applications in other areas, on land and offshore. This paper demonstrates the importance of staying operationally and mechanically simple when executing sophisticated, deep, directional well plans.
Enhancing the Safety and Reliability of Subsea Drilling Operations by the Use of ‘Routine’ Case Operating Envelopes
Authors: Burton K. , Ferguson G. , King G. W.
Published: December 2007

A major UK JIP has recently been completed, its purpose being to identify appropriate limits within which subsea drilling operations can be performed. One of the main deliverables from the JIP has been acceptable Operating Envelopes for ‘routine’ case subsea drilling operations. This paper presents a definition of what constitutes a ‘routine’ case drilling system; typical operating envelopes are also presented. Application of this information wil I greatly reduce the requirement for case-specific analysis of subsea drilling operations; indeed, the intention is that for ‘routine’ case operations, the need for analysis will be completely eliminated. The data contained in this paper forms the basis of a forthcoming UK Institute of Petroleum Guideline publication.
Drilling Performance Improvements Using Downhole Thrusters
Authors: Reich Matthias , Hoving P. G. , Makohl Friedhelm
Published: December 2007

Thrusters generate weight-on-bit by using drilling fluid hydraulics. The pump-open behaviour of thrusters de-couples the lower part of the bottom hole assembly from the remainder of the drillstring, and in so doing provides a constant, controllable weight-on-bit (WOB) that dampens out axial vibrations and shocks.

In more than one hundred and twenty jobs, thrusters have proven their ability significantly to improve drilling performance in holes with vibration- or shock-related problems. The technique has been used to increase overall penetration rates and bit lives, improve steerability and reduce downhole failures in hole sizes from 12 1/4" to 3 7/8" diameter, in both horizontal and vertical wells, and at depths to ~5400 m (1650 ft.). The system has been used mainly on fixed rigs, but also on floating rigs, substantially reducing cost per foot.

As the thruster interacts with other hydraulic components of the drillstring (bit, mud motor, restrictor subs, MWD pulser), the proper tuning of the drilling system is required to obtain optimum performance. This paper shows the function and principle of thrusters, it explains possibilities and limits for their use, and details criteria for the optimum thruster in certain applications. Detailed field data from 4 wells in 4 geological areas are presented.
Environmental Studies For A Proposed Arctic Marine Terminal
Authors: Ranft Fracis E. , McCollom Robert L.
Published: December 2007

Investigations are presently underway to determine the suitability of several areas along the Arctic coastline as potential sites for petroleum storage and marine terminal facilities. The broad, shallow shelf along the Alaskan Arctic coast presents considerable engineering design problems for the construction of a marine terminal which would accommodate deep draft tankers; however, several suitable sites appear to be present along the Canadian Arctic coast.

In the Spring of 1969, a field investigation was conducted at Herschel Island, Canada near the Mackenzie Delta to determine if subsurface conditions and other environmental factors are favorable for possible development of marine terminal facilities.

Deep water access to the island is provided by a submarine canyon which comes provided by a submarine canyon which comes to within a few miles of the shoreline. A natural deep water basin, probably formed by glacier-ice thrusting, exists immediately adjacent to the protected harbor at Thetis Bay on the south side of the island. A submarine ridge consisting predominantly of clays and clayey silts separates the submarine canyon from the deep water basin.

Herschel Island with its protected harbor and natural deep water basin offers some distinct advantages over other potential sites. The only major drawback appears to be the necessity of dredging a channel to connect the deep water basin with the submarine canyon. To a large extent economic considerations will determine the feasibility of utilizing Herschel Island as an Arctic marine terminal in the future.

Introduction

Technical and economic feasibility studies are being conducted to determine methods by which the recently discovered crude oil and gas reserves of Prudhoe Bay and the Mackenzie Delta can be transported to the major market areas of the eastern and mid-western united States. Some of the plans being considered include:

A Trans Alaska pipeline from Prudhoe Bay to Valdez, Alaska which would connect by conventional tanker with a Trans United States pipeline extending from terminal facilities pipeline extending from terminal facilities in Puget Sound across the Cascades and Rocky Mountains to the eastern markets;
Ground-Water Flow Systems and Underground Nuclear Testing
Authors: Fiero G.W. , Maxey G.B.
Published: December 2007

Ground water is the only possible transport vehicle of radioactive contaminants released by an underground explosion. Consequently, safety considerations require an accurate determination of the ground-water flow directions and velocities in the vicinity of the nuclear detonation.

Recent advances in knowledge regarding ground-water flow systems have created new theoretical models to describe the nature of ground-water movement. Many of the physical parameters which are involved in parameters which are involved in ground-water movement also control the movement of other subsurface fluids. Consequently, oil and gas stimulation experiments may be better predicted by an understanding of predicted by an understanding of current ground-water concepts.

Ground-water flow in the vicinity of an underground nuclear explosion may be divided into the preshot (natural) and postshot (induced) systems. Several examples of these systems and their relationship to radionuclide dissemination are given. A thorough knowledge of the system is necessary for each unique location of an underground nuclear explosion.

Introduction

The only possible transport vehicle of radionuclides generated by an underground nuclear explosion is ground water. In order to determine the concentrations of the radioactive material in space and time, the velocity and direction of ground-water movement must be known.
Learning to Learn
Authors: Keon Billy V.
Published: December 2007

It is estimated that an engineering student will be technically obsolete from 5–10 years after he graduates if he does not continue to learn after graduation. A new teaching strategy, Self-Paced Instruction, has recently been applied to engineering courses. This technique has the advantage that it teaches a student to learn for himself as well as giving him the technical content of the course. On the basis of our experience to date, this method is a great success as judged by student learning, motivation, and enjoyment.

Introduction

Due to the probable technical obsolescence of a student who fails to continue studying after graduation, one of the primary responsibilities of modern engineering education is to design the classroom environment to encourage the student to enjoy learning. If this is successfully achieved, psychology indicates that the student will naturally gravitate toward a continuation of his education after his formal studies are completed. Modern learning theory has developed a teaching strategy called PSI (personalized or proctorial system of instruction) in which a positive attitude toward learning as well as specific "learning skills" are developed without sacrificing coverage of course material. PSI was applied at The University of Texas in a senior engineering course.
Evaluation Of Gas Storage Well Completions With Well Logs
Authors: Smith B.A. , Neal M.R.
Published: December 2007

This paper was prepared for the 45th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Tex., Oct. 4–7, 1970. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Many of the problems connected with the underground storage of natural gas, in both aquifer and depleted reservoirs, can be solved by the proper application of modern wireline logging tools.

Well logs are useful in gas storage wells for the location and inventory of gas-bearing zones, determination of levels where gas enters or is produced from the formation, determining well deliverability, and the location of casing leaks as well as points where the pipe is defective due to corrosion. logs run after the well is completed can help to evaluate the effectiveness of a stimulation process or the mechanical integrity of the completion. logs run at intervals, as the storage well is produced, can define changes in gas saturation movement produced, can define changes in gas saturation movement of fluid contacts, and growth of the gas bubble, thus permitting a periodic inventory.

Major changes in injection patterns and withdrawal rates are usually symptoms of problems. Suitable logging programs can help define these problems and indicate the remedial action necessary to bring the field back to maximum efficiency.

The open-hole logs and the logs run immediately after completion provide valuable background information for the interpretation of logs run later in the life of the well. In existing storage fields, where background information is not available, data must be gathered in order to help define the existing problems. A thorough evaluation of the existing subsurface hardware must also be made.

Small-diameter tools and pressure-control systems are available with which most logging operations may be made in either tubing or casing without interrupting the well operation.

Field examples from gas storage projects in several different areas are used to illustrate the interpretation techniques.
A Pragmatic Approach to Risked Production Forecasting
Authors: Singleton Ian
Published: December 2007

Short term production forecasts (up to 18 months) have tended to be single point production forecasts with no estimate of the possible range of outcomes. In addition these forecasts have tended to be mainly concerned with reservoir potential and have not fully incorporated well, facility and export performance.

This paper describes how improved understanding of the uncertainty in production can be quantified and how this information can be used to improve field management.

The method was developed for a prolific North Sea field however the concept is applicable to all fields.
Present Situation and Development Tendency of China's Petroleum Market
Authors: Shaohuai Zhang , Jian Hu
Published: December 2007

The paper presents an analysis and evaluation of the current situation and developmental trend of the petroleum market of China. The authors believed that the marketing deformation of petroleum industry and development of petroleum market of China is restricted by the change of whole economic system in China. This paper discussed the aspects of changes of Petroleum Market and predicted the developmental trend of China's petroleum market, which includes the relationship between supply and demand, price fluctuation and characteristics of petroleum source allocations, etc.
Simulation of Surface Light Hydrocarbon Recovery Process in the Compositional Simulation
Authors: Huan Guan Ren , Wang He Mei
Published: December 2007

This paper describes phase behavior simulation of complex process station in the light and volatile oil reservoir simulation, using equation of state method. The technology process of the station includes two-stage separation, crude oil stabilization, three-phase separation, shallow cooling, deethanization and debutaiuzation. In the new compositional model, the simulation of surface complex process station is considered with combination of reservoir simulation based on uniform parameters of equation of state. The differential flash method and nested successive substitute iteration method have be used for solving dynamic phase equilibrium problem for deethanizer and debutanizer in the simulator. The simulator also considered process and product quality controls. The simulator provides calculation results for production of stabilized oil, sale dry gas, light oil, naphtha and LPG. It is very useful for light oil and volatile oil reservoir simulation.
Optimization of a Mature Waterflood in the Long Beach Unit: Government and industry Joint Venture
Authors: Leone Joseph A. , Hemphlll James R. , Woodling Gary S.
Published: December 2007

The Long Beach Unit with 3 billion bbls of oil originally in place, is a part of the giant Wilmington Oil Field, the 4th largest field in the United States. In 1989, ARCO approached the City of Long Beach and State of California with a proposal to provide technology and capital needed to redevelop the field. The optimized waterflood program (OWP) agreement took effect on January 1, 1992 and today the LBU is producing more than 25% above the oil rate predicted from the base case decline. In addition, substantial reductions in both drilling and operating costs have been achieved. This paper discusses all aspects of the OWP agreement, including negotiations, technical studies, implementation, management philosophy and critical keys to success.
Managing Remote Field Operations In The Cooper-Eromanga Basin, Australia
Authors: Taylor Neale F.
Published: December 2007

The remote, desert location of the Cooper-Eromanga Basin in central Australia provides an ongoing challenge to maintain cost effective operations and development.

The uniqueness comes from the lack of regional infrastructure typical of similar, mature, remote, onshore operating provinces in the USA and Canada, the large scale and sparseness of the operations, and the harshness of the arid environment. It is hoped this paper will provide insights to operating in remote locations, including the inland basins of China.

Operating costs have been reduced in real terms and examples are given of the innovations and technologies being used to achieve continuous improvement. Benchmarking indicates lower costs to look-a-like areas in the USA/Canada; operating efficiencies offset the costs of additional infrastructure. The future will require additional cost reductions to avoid erosion of profitability due to declining oil volumes and increasing numbers of facilities.

The key to success is in recognising the need for change and challenging every aspect of the operation. Gains are likely to come from a myriad of small improvements rather than a few large gains.
Outlines and Structural Features of the Simple Development Engineering for W 10—3 North Marginal Oil Field
Authors: Guowei Gu , Guanqun Lin , Dongyuan Zhang
Published: December 2007

The simple development engineering project of W10-3 North (W10-3 N) oil field has its own significance in the history of the simple oil field development for China's offshore oil industry and is a crystal of research fruits on " early production system" in the offshore engineering field of China. This article introduces the development of the marginal oil fields and the conversions of the two production platforms from drilling rigs and their engineering features. It provides necessary and referable information for understanding the cases of the simple development engineering for marginal oil field in Beibu Gulf and the conversions of jack—up rigs "Nai Hia No. 1" (NH1) and "Bo Hai No. 6" (BH6) to double purpose of drilling and production rigs.

Key words: marginal oil field, simple development engineering
The Computer Simulation of the Interaction Between Roller Bit and Rock
Authors: Ma Dekun , Zhou Desheng , Deng Rong
Published: December 2007

In this paper, the surface of each tooth of roller bits is represented by scores of points, whose 3-D compound coordinates are used to reflect the shape and size of the tooth. Thus, the cutting structure of the bit together with their movement is represented by the time-sequence of the coordinates of the several thousand points. Hence, the computer simulates the roller bit.

In the simulation, the bottom hole that changes with drilling is represented, according to the sequence of time, as a series of time points. And the bottom hole at each time point is represented, according to space, as tens of thousands of points, whose 3-D compound coordinates are used to express the shape and size of the bottom hole at an arbitrary time. The changes of the bottom hole with drilling are described by a recurrence model made up of the bottom hole at each time point. Hence the reproduction of the bottom hole is on computer.

The well bore is dealt with the same principle as the bottom hole.

The interaction between the roller bit and the rock is represented by the balance model of the vertical and the lateral interactions

The index, inclination, the shape and size of rock fragile breakage by a contacting tooth at any time are calculated by the fragile criterion model and the rock breakage model. The craters with various shapes are formed by the rock fragile breakage and the amount of the rock occupied by the tooth directly.

BRIAS, the simulation software thus set up, can be used to analyse all the interactions in the process of drilling. Detailed experiment data have proved that the simulation software is able to well reflect the effects of the subtle differences of bit structure, WOB and rock properties upon the rotation rate and the torque of the bit.
Innovative Approach in Slim Hole Drilling
Authors: Schenato Adelmo , Calderoni Angelo , Grandi Maurizio , Cesaroni Renzo
Published: December 2007

The engineering and design of an innovative drilling rig, particularly tailored for cheap / slim hole drilling in mature areas, is presented in the paper along with results obtained by the prototype in field trials.

The project has been defined according to a specific scenario in Italy, which includes marginal gas fields both onshore and offshore. The market is very mature and standard rigs, suitable for slim hole application, are in keen competition, nevertheless the candidate fields are not economically developable if conventional technologies are applied. The ongoing project activity focuses the attention to land operations although offshore can be very attractive for the proposed technological solution.

Innovation has been targeted not only to reduce dimensions and volumes related to the drilling activity but it considered the requirements of high mobility (situations where drilling time is comparable to mob-demob) and reduction in personnel.

The main innovative features concern the hoisting equipment and the automatic pipe handling including a vertical pipe racking system.

The technology has been implemented from an existing water well rig in use since several years, obviously not applicable as it was to oilfield operations. The prototype was assembled in order to provide adequate information regarding equipment reliability, necessary improvements and limits of the proposed technology to design and build a target rig.

Results are related to the experience gained in drilling three wells in a very well known area.
Use of Corner Point Geometry in Reservoir Simulation
Authors: Ding Y. , Lemonnier P.
Published: December 2007

At the present time, field-scale reservoir simulations are usually carried out with Cartesian grids. However, the use of these grids does not permit a good representation of reservoir geological features and reservoir description. Different approaches have been investigated to overcome the disadvantages of Cartesian grids. The corner point geometry (distorted grids) is often used as an alternative for complex full-field studies. This approach can better adapt the grid to reservoir boundaries, faults, horizontal wells and flow patterns and is easily used in standard finite difference reservoir simulators. The key problems for this technique are the preservation of the accuracy of fluid flow modelling and well treatment. In this paper, we will present a technique well suited to the corner point geometry and discuss its application range. Results are presented for test cases, comparing different control-volume type approximations.
Simulation of Black Oil Reservoir on Distributed Memory Parallel Computers and Workstation Cluster
Authors: Zhiyuan Ma , Fengjiang Jing , Xiangming Xu , Jiachang Sun
Published: December 2007

This paper describes parallel linear solvers of LSOR and preconditioned ORTHOMIN ( K ) on parallel computer based on T8OO Transputers and SUN workstation cluster ( with Ethernet network).

Both Algorithms show a high degree of parallel efficiency on Transputers, whereas only full impliicit method and large petroleum reservoir problems can observe a high efficiency on SUN workstation cluster.

The key issure in parallelization of reservoir simulator on workstation cluster is the improvement of communication speed.
Testing the Yacheng 13-1 Gas Reservoir: Design, Conduct, Analysis and Impact on Field Management
Authors: Kamal M. M. , Brown D. S. , Haaland K. S.
Published: December 2007

Properly designed, conducted and analyzed transient tests can be used to determine reservoir behavior and well conditions and estimate reservoir properties needed for field management. Testing the Yacheng 13-1 wells provides a case history for achieving these objectives under conditions of high temperature. The Yacheng wells encountered natural gas at a temperature of 350°F (177°C) and a pressure of about 5600 psi. This paper discusses the testing process and the experience of ARCO China in testing the Yacheng 13-1 development wells. This experience shows the key items needed to assure a successful test in a difficult environment.

The key items are determining the test objectives, designing a test that would achieve these objectives, estimating the pressure and temperature of the well during the test, selecting the proper tools and equipment to obtain the needed measurements, carefully coordinating the tasks between operating and service companies personnel, monitoring the test data in real-time to change the test procedure if needed, analyzing the data to estimate the well/reservoir system properties and finally, using the results to update the testing procedures for subsequent wells.

The tests performed included modified isochronal, drawdown and buildup tests. Tests had to be designed such that PVT-quality samples could be obtained to help design the production and transportation facilities. Carefully designing and conducting the tests, aided by the ability to perform real-time analysis to alter the testing procedure, enabled the operator to obtain the needed information about the well/reservoir system. The paper shows how the information is intended to be used in managing the field.
The Rheology of Chinese XD and ZW BorateCrosslinked Fracturing Fluids and their Proppant Transport Capability
Authors: Zhao Zhong-yang , Cui Mingyue , Conway Michael W. , Chang Frank F
Published: December 2007

The Fracturing and Acidizing Technical Service Center (FATSC) of CNPC and STIM-LAB Inc.jointly studied "Xiando"( XD) and "Zhaoren" ( ZW) polymers to understand their theological properties and their proppant transport capabilities when crosslinked with borate ions. A series of bench top tests were conducted on XD, ZW, and guar, including residue measurement, base gel viscosity, and single particle settling, to help define the crosslinker concentration required to optimize the fluid systems. A rheometrics pressure rheometer(RPR)was used to measure the viscoelasticity of the borate crosslinked fluids, anda large scale rheology simulator was used to observe the dynamic proppant transport under shear conditions.

In the steady shear mode, the RPR measured three different regions in the shear stress-shear rate plots, including a shear thinning region at low shear rates, a shear thickening region at intermediate shear rates, and a shear thinning region at high shear rates. The 0.6%(50 1b/1000 gal) XD and ZW base gel showed the same characteristics as typical thin polymer solutions. When crosslinked with borate at low temperature, the storage modulus G' values showed good elastic properties for the fluids. At temperatures up to 66 °C, the G’Values are higher than 19 dynes/cm2, which is proposed by de Kruijf[1]

to be the minimum for a crosslinked fluid to have good proppant transportcapability.

Large scale rheology simulation and proppant transport visualization showed the XD-borate crosslinked fluid system caused very low pressure drops in the pipe rheometer, indicating XD's good friction reduction characteristics. The friction of XD base fluid is only 20% of that of water. The observation in the slot rheometer indicated excellent proppant transport capability. There was no observed bulk settling and little movement between particles. The pressure drops of ZW-borate system in pipes and slot were higher, although the proppant transport was almost perfect. There was slight interparticle movement but no bulk settling observed.

Two case studies are presented to show the successful applications of XD-zirconium-borate and ZW-borate systems to Chinese oilfields.
Application of Pressure Transient Test Normalized Graph Analysis in China's Oilfields
Authors: Hui-nong Zhuang , Neng-qiang Liu
Published: December 2007

Based on the further study on pressure transient testing theory in various formation, the paper drew up 80 pieces of normalized graph. By combing the pressure log-log curve and semi-log pressure curve, the graphs use brief words to describe the flow characteristics by segments. 112 field testing examples optimized from 10 large and middle scale oil and gas fields in China are given to do compare explaination.( This paper will introduce partly) Among the 80 normalized graph, 49 graphs aimed at homogeneous formation and give out a "Location analysis method". So the homogeneous model is classified by figure parameter CDe2S and positional parameter kh/µC and result in a classified table. From the table, we can easily find the law of radial flow section apparence from the testing information in order to improve the quality of well testing. The other normalized graphs are aimed at the double porosity model, fractured formation model, boundary interference model, composite system, partial penetration formation and stimulated formation. By using this graphic analysis method, the geologists and reservoir engineers can get a visable and clear physics concept related to the formation characteristics. By combining the well testing information and geology, geophysics, well logging and well completion information, the paper will be a great help in improving the well testing interpretation quality and the application level of well testing information in oil and gas engineering.
Renewed Exploration and Appraisal of the Viking Area: A Case Study
Authors: Palmer John R. , Tyberø Geir , Riches Hugh A. , Dudley Graham , Marsh Marcus M.
Published: December 2007

First production from the Viking fields began in 1972 and at its peak a total of 13 platforms produced at rates up to 950 million cubic feet per day from 20 wells and was supplying 12% of the United Kingdom’s natural gas requirements. In addition, several prospects were drilled in the early 1970’s but, due to disappointing results, were viewed as un-economic and consequently were not pursued for development.

Since discovery in the late 1960’s of the Viking A and B fields and associated satellites, exploration and appraisal within the Viking contract area has identified five possible new gas accumulations named the Viking Extensions. Appraisal of these extensions commenced with the remapping of the Viking contract area with proprietary 2D seismic data acquired in 1983 and 1987, supplemented with traded seismic data from adjacent block operators.

However it was only the re-negotiation of the gas sales contract and the removal of the Gas Levy in 1992 that provided favourable marketing conditions for the development of additional Viking gas production and initiated the current appraisal programme for remaining reserves. This programme began with acquisition of a 3D seismic survey in 1993 and these data and subsequent drilling have resulted in very promising initial results. It is expected that as this latest evaluation of the Viking extensions and remaining exploration prospects reaches it’s full conclusion, between 750 and 1000 Bcf of additional gas reserves will have been realised. This will provide the opportunity for many more years of renewed life from one of the oldest producing areas in the North Sea.
Casing Damage Caused by Jet Perforating
Authors: Godfrey W.K. , Methven N.E.
Published: December 2007

This investigation has confirmed and extended the work by Bell and Shore, on casing damage by perforating. Perforating with the hollow carrier jet causes only slight deformation and, does not damage the casing. The expendable jet causes more deformation and possible damage in the form of cracks and possible damage in the form of cracks and splits. Tests under down-hole conditions show that expendable jets do not cause damage to (1) high-strength casing without flaws even when nonsupported, or (2) high-strength casing with flaws (laps and seams) that is well supported. The decreasing trend of casing deformation with increasing strength factor continues to hold through the high-strength P-110 and V-150 casing. The casing deformation P-110 and V-150 casing. The casing deformation decreases as the cement support changes from non- to semi- to well-supported. In scaled model test, 6 or fewer perforations/ft do not reduce the collapse resistance of casing significantly.

In the field, we recommend that the hollow-carrier jet gun be used for perforating low-strength, poorly supported or old, corroded casing. Expendable jet guns with nominal charges will not cause damage if the casing strength factor is high and the casing is well supported.

Introduction

Casing damage caused by gun perforating has been investigated by several authors. Their reports have not agreed entirely and of course their work could not be comprehensive enough to cover every field condition. The work by Bell and Shore is the most complete. Our work was undertaken to check and extend the study by Bell and Shore and thereby extend our knowledge of casing damage by jet perforating.
Quantifying the Benefits of Multi-Lateral Producing Wells
Authors: Gallivan J. D. , Hewitt N. R. , Olsen M. , Peden J. M. , Tehrani D. , Tweedie A. A. P.
Published: December 2007

Drilling and well completion technology have progressed to make it possible to drain reservoirs with multiple branching wellbores connected into one tubing string - usually known as multi-lateral wells. However, the economic benefit of multi-lateral wells has not been reliably understood up to now because of uncertainties in their cost and performance. This is in part due to technical difficulties in predicting flow performance and drainage efficiency. A number of operating companies in the North Sea have sponsored a research and development project to tackle these difficulties. This paper, based on that project, shows how analytical and reservoir simulation methods have been combined to predict the productivity and sweep efficiency for simple cases in homogeneous reservoirs. The results have then been extended to cover irregular well geometries in realistic heterogeneous reservoirs. The paper concludes with an assessment of the potential and anticipated benefits of applying multi-lateral wells in a range of reservoir types characteristic of the North Sea. The emphasis is on the evaluation processes used.
System Study Of Oil Spills Cleanup Procedure
Authors: Ladd Richard W. , Smith David D.
Published: December 2007

The petroleum industry in the United States produces transports, refines, and markets billions of barrels of crude oil and petroleum products annually. That it had done so without a real serious incident up until the much publicized Torrey Canyon disaster and subsequent oil spills is I believe a credit to the industry. An Oil Spill Sub-Committee of the Engineering and Technical Research Committee of the Committee for Air and Water Conservation of the American Petroleum Institute was formed to focus the industry's concern and attention specifically to this problem. problem. The logical first undertaking of the newly constituted sub-committee is the subject of this presentation. That is a systems study to define the problem and to evaluate presently available control equipment, devices and techniques to deal with the problem. The contract let in connection with this initial study for the sub-committee was with the Dillingham Environmental Company, La Jolla, California.
Economic Justification for Fracturing Moderate to High Permeability Formations in Sand Control Environments
Authors: Stewart B. R. , Mullen M. E. , Ellis R. C. , Norman W. D. , Miller W. K.
Published: December 2007

This paper discusses case histories of more than seventy completions requiring sand control. Approximately half of these wells were gravel packed (both slurry and water packs) between 1990 and 1995 while the remaining completions were fracture stimulated (frac-packs) from 1992 through 1995. The case histories include: geopressured oil reservoirs of moderate permeability, normal pressured high perm oil and gas formations, partially depleted high perm gas sands, and shallow dry gas formations. Results of bottom hole pressure transient analyses are included that compare skin values and completion efficiencies of both gravel packed and frac-packed completions. Production plots and decline curves are presented depicting accelerated as well as improved reserve recovery with the frac-packed completions. The associated costs of frac-packing is discussed along with a net present value analysis justifying these costs.
Economical Management of Sand Production by a Methodology Validated on an Extensive Database of Field Data
Authors: Sanfilippo F. , Ripa G. , Brignoli M. , Santarelli F. J.
Published: December 2007

From a scientific point of view, sand production prediction is one of the most complex problems that has been addressed by the oil industry over recent years. Yet, the economical importance of a sound prediction methodology leading to an optimized completion strategy is such that many corporations have dedicated vast resources towards the solution of this problem, De facto surveying the literature reveals that a large number of models have been proposed to predict sand production. Unfortunately none of them has been validated to such an extent that it can be considered as a standard by the industry.

As a consequence a large gathering of sand production data was undertaken. After proper data analysis it is possible to demonstrate that, from the engineering point of view, sand production is a relatively simple phenomenon governed by a few key parameters. Available models are prescreened for their capacities to account for these parameters. The selected models are then calibrated and validated against sand production field data with a sufficient degree of accuracy for operative purposes.
Flexible Bit: A New Anti-Vibration PDC Bit Concept
Authors: Defourny P. , Abbassian F.
Published: December 2007

This paper introduces the novel concept of a "flexible" polycrystalline diamond compact (PDC) bit, and its capability to reduce detrimental vibration associated with drag bits. The tilt flexibility, introduced at the bit, decouples the dynamic motion of the bottom hole assembly (BHA) from that of the bit, thus providing a dynamically more stable bit. The paper describes the details of a prototype 8-1/2" flexible bit design together with laboratory experiments and field tests which verify the concept.
Mitigation of Multiple Fractures from Deviated Wellbores
Authors: Hainey B. W. , Weng X. , Stoisits R. F.
Published: December 2007

While over six hundred Kuparuk A Sand wells have been hy-draulically fractured or re-fractured successfully from deviated wellbores, a number of wells in the field have not responded to the conventional fracture treatments. In these wells, the conventional design resulted in premature, near-wellbore screenouts, with low proppant placement, and consequently, poor productivity. A symptom common to each of the failed treatments was a near-wellbore friction pressure loss too high to be explained by perforation restriction or simple fracture twisting and turning. An extensive analytical study of hydraulic fracture initiation and propagation from deviated wellbores suggested multiple fractures as a mechanism to account for the abnormally high near-wellbore friction pressure loss and the reduction in fracture width, A model was developed (XFRAC) which correlates these responses to formation stress, wellbore parameters and treatment conditions. A counter-intuitive fracture treatment which employed lower pumping rates combined with higher viscosity fracturing fluids was designed to minimize the formation of multiple fractures and increase fracture width. This unconventional design has been successfully pumped in eleven wells which exhibited the premature screenout problem. Proppant placement was increased over ten fold with a tripling of post-frac production rates and a 35 percent increase in estimated recovery.