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The petroleum engineer is often required to estimate the pressure production performance of an oil well in order to determine its productive capacity. This paper discusses various methods that have been proposed in the literature for describing individual well performance in solution-gas drive reservoirs. The forms of the oilwell deliverability equations will be presented as well as methods for predicting future performance. An example will be used to illustrate and identify data requirements for each method.

Recent developments in stimulation practice have resulted in two or more fluid systems being used continuously during a treatment. Fracture acidizing, for one, has involved the use of a highly efficient pad fluid preceding the acid into the fracture. In the use of the crosslinked gels, it is common practice to precede the gel-sand slurry into the fracture with a pad fluid of an entirely different character. Where these techniques are used, it is useful to know the rate at which one fluid is displacing another and the location of the interface between these two fluids.

Stanolind Oil and Gas Company (now Pan American Petroleum Corporation introduced their "Hydrafrac" process of well stimulation to the petroleum industry in 1948." In the following year, the first commercial fracturing treatment was conducted, thus introducing the petroleum industry to one of the most outstanding well stimulation practices of the past two decades." Since the initial fracturing treatment was executed in 1949, over 400,000 additional treatments have been performed in the free world, as well as an untold number behind the Iron Curtain." During the past 18 years, many advancements

Water preflushes have been used for many years to precede acid fracturing treatments. One of the primary functions performed by the preflush is to establish injectivity into the reservoir before acid fills the tubular goods. Preflushes also perform other functions which can contribute to more efficient use of acids and provide greater effectiveness from acid fracturing. This paper discusses the influence of preflushes on acid fracture designs and describes preflush systems which have been used successfully.

This paper includes a description of the dynamometer instrument used, discussion of its application in a typical hydraulic pumping installation, presentation of actual dynamometer cards with pertinent hydraulic pumping data, and interpretation and analysis of actual dynamometer cards considering pump operation and well conditions.

A cooperative study of the Grayburg/San Andres reservoir is being conducted in response to the United States Department of Energy's Class II Oil Program. The purpose of this study is to preserve access to existing wellbores by identifying additional reserves. Production problems associated with shallow shelf carbonate reservoirs are being evaluated by a technical team integrating subsurface geological and engineering data with 3-D seismic data.

With the aim of developing a more reliable connection to be used in the current artificial lift systems, Tenaris has worked in an innovation process whose outcome was the premium connection product family for sucker rods. This paper explains the comparison between the premium connection design and the API connection design through finite element analysis methods, the product validations full scale tests for beam pumping and progressive cavity pumping, and the application recommendations.

The current reservoirs declination and depressurization in combination with the continuous reduction of incorporated reserves to the oilfields has challenged the engineer staff to either increase the extraction rate, with a significant increase of the water volumes applied in order to pressurize the field and/or pushing the limits of the artificial lift system (ALS) using biggier pumps and equipment in combination with deeper wells.

Utilization of computer simulations addressing the placement of chemicals and/or cements for remedial repair workovers has demonstrated valuable assistance in successfully repairing integrity problems. Various situations encountered where casing leaks, isolation failures, and other repairs to wellbores and inter-reservoir communications may be addressed with a variety of solutions. Selection of the right solutions and how to selectively place them into the problem areas have historically needed a method to assist in the control and monitoring during design and in real-time operations.

Two similar but somewhat different problems exist in preparing old producing wells to be injection wells and stimulating injection wells currently in use. Recognition of the problems to be solved is of prime importance. A several step procedure may be required once the problem have been defined. A discussion of the problems which may exist and possible solutions for these problems is included.

Beginning January 1, 2002 competitive forces will be introduced into the Texas retail electricity market. The march to a competitive market was set in motion in June 1999 by Governor George Bush signing Texas Senate Bill 7 or SB7 into law. SB7 begins a process of unbundling or separating the utilities" functions into three distinct areas - generation, transmission and distribution and REPs (Retail Electric Providers). SB7 will bring profound changes in the way we purchase power at our homes and in our professional lives. Deregulation will bring choice.

New artificial lift technology, Pressure Actuated Chamber Technology, PACT, is proving to be a perfect choice for San Juan Basin producers searching for a more efficient and effective artificial lift method to produce CBM and other shallow, low volume gas wells. PACT has shown remarkable success in replacing both sucker rod pumping systems and swabbing as a gas well deliquification method. The PACT system has no moving parts at the surface, a very small footprint, uses virtually no energy and doesn"t require a pulling unit to install or service.

Because of sedimentation processes over long geological times, hydrocarbon reservoirs are likely to be multilayered. For practical purposes, in the analyses of pressure and rate transient data the reservoirs are commonly treated as a single-layer model. Petroleum engineers better comprehend the models and analyses of single-layer systems than those of multilayer systems. As long as single-layer analysis yields acceptable results, the engineers tend to use single-layer models in analyzing multilayer data.

This paper presents a discussion of the production history, reservoir performance, and operational problems encountered for the pressure maintenance program in the Strawn Sand Reservoir in the Truby, North (Strawn) Field of Jones County, Texas. Primary energy in the reservoir was supplied by solution gas with a partially effective water drive.

A theoretical basis for pressure transient analysis of gas wells with emphasis on the real gas pseudo pressure approach is outlined. An analysis procedure is developed to analyze wells either injecting or producing predominatly CO2 or enriched gas. This procedure is used to calculate flow capacities and skin factors from pressure transient tests in injection and production wells from two CO2 projects. A computer program is documented which aids in the analysis of gas wells with the real gas pseudo pressure.

The objective of primary cementing is to support the pipe and achieve a seal so that the desired fluids can be produced from the well. Although a lot of effort is spent in designing for effective fluid displacement in the annulus, displacement in the pipe is frequently overlooked. When fluids are being circulated down the pipe, the balance of forces is not correct for efficient displacement. The heavier fluid is on top, displacing the lighter fluid below it, with buoyant forces causing the heavier fluid to tend to fall through the lighter fluid.

A Preventive Maintenance (PM) Program has been established in the southeastern New Mexico portion of Continental Oil Company's production department operation. The PM system has been in operation for 12 months and covers over 2000 separate pieces of major surface equipment. The concept of preventive maintenance is not new in production operations; however, most operating organizations incorporate PM and operations in one organization. The primary disadvantage of this type of setup is the secondary priority PM receives.

Our entire economy is sick. The illness is generally diagnosed as over-production or under consumption. The disease has become epidemic in the oil producing industry. Some very drastic curative measures are being advocated. The medicine generally prescribed is hard to take and very expensive. Actually, the causes of the malady cannot be eradicated. Barring unthinkable catastrophe, we can expect low allowable and proration for a number of years. Available cheap foreign crude makes prospects for higher crude prices quite unlikely.

ESP systems are difficult to operate in plumping wells. This is a common operating condition in CO2 floods. A flowing well simulates a no-load or gas locking condition at the surface. The controller then shuts the well down as the underload parameters are exceeded. This repeated cycling is damaging to all components in the system. An integrated control system utilizing a downhole sensor, surface controls and RTU can been utilized to prevent unnecessary shutdowns and premature failures. This system by-passes the underload parameters but limits the motor operating temperature to 200_F.

It is the purpose of this paper to point out one of the most important factors to be considered in the proper design and correlation between the tubular material and the wellhead assembly as related to the compressive overload of the surface casing.

Many production companies in the Haynesville Shale formation have experienced production tubing problems like corrosion and scaling. They also expect to see liquid loading problems due to the water left after fracturing. Most of the frac jobs in the Haynesville Shale use at least 40,000 bbls of water per stage. The Haynesville Shale is typically 10,000 feet below the surface and about 200 feet thick. The reservoir has a bottom hole pressure of approximately 9000 psi and a bottom hole temperature in the range of 250_

The decrease of cement strength with increased temperature and age was first reported by oil field related researchers in the early 1950's as a result of the growing trend toward deep well completions. This phenomenon is generally known as "Strength retrogression" and has been an increasingly important problem to consider ever since. Several methods have been employed by service companies to counteract strength retrogression and each will be discussed here in detail.

Successful design of primary and remedial cementing procedures in fractured formations requires a precise analysis of down-hole conditions, and careful definition of design objectives. Collection of fracturing pressure data is stressed, and methods for applying this information to cementing design are the primary considerations. Remedial cementing is regarded as the more difficult design, and emphasis is placed on this phase of cementing. The use of controlled water loss cement, packer applications, and placement techniques are considered as a basic part of remedial design.

The techniques for cementing oil and gas wells vary with geological conditions and requirements of the operator. These techniques have developed through usage and engineering studies. All techniques are based on fundamental chemical and physical considerations. To develop these basic principles, the properties of cement are considered in detail. Modification or control of these properties by use of additives is studied with the individual functions. Special consideration is given with the individual functions.