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In the last decade, systems analysis methods were widely used to describe the performance of flowing and gas lifted oil wells, several applications dealt also with gas wells. The present author's aim is to apply these procedures to sucker rod pumping and to develop calculations for modeling the operation of rod pumped wells. A discussion of systems analysis methodology is given first. Then, a sucker rod pumped well is analyzed and considerations are given on the application of these methods to describe the performance of a pumping system.

A pressure buildup on a pumping well may be conducted by either of two methods. Direct measurement, of course, involves placing a gauge downhole. This presents special problems, however, for a pumping well. Since this procedure involves pulling the rods and pump in order to get the gauge downhole, it is usually economically infeasible. In addition, this "pulling" process introduces a new transient into the formation which adversely affects the analysis unless the well is restabilized once the gauge is downhole.

Since the inception in 1947 of hydraulic fracturing as a method of stimulating oil and gas wells, fractured wells have become a commonplace throughout the world. This is particularly true in regions noted for low permeability and accompanying low productivity. Transient pressure test conducted in fractured reservoirs are subject to unconventional behavior which requires special interpretational skills and procedures. The purpose of this paper is to discuss those methods of pressure analysis which have been most successfully applied to wells that intersect single-plane vertical fractures.

Production logs that are available to the industry today obtain a more accurate account of production; the main reason for the accuracy is that the well is logged in the dynamic production state. Interpretation of the production log is dependent upon understanding the mechanics of the well and the function of the combinations of logs used. The following approach is important in obtaining and interpreting good production logs: 1. Properly prepare the well to be logged prior to survey. 2. Have a basic knowledge of the tools used in each log.

This paper will describe the sizing techniques for field applications using variable frequency (speed) drives (VFDs or VSDs) with electric submersible pumps (ESPs). The field installations will be described along with reservoir and production information. Then the controls available with the VSD's and their uses will be discussed. Finally the various control and transformer settings for different applications will be presented.

The average person driving down the highway past a pumping unit working away in the adjoining field has no conception of the many problems involved in the selection of this unit for its particular job and the constant continuing care that must be expended to keep it doing its assigned task year after year. All of this falls into the province of the oil business with the major responsibility on the production department of each company to keep the pumping units going and the oil coming.

High density liquid corrosion inhibitors have many advantages over conventional inhibitors in problem well treatments. High fluid level pumping wells, low pressure gas wells, high pressure gas wells, flowing wells with packers and wells with static water columns in tubing strings that have been difficult or impossible to treat with conventional inhibitors can now be treated effectively and economically with high-density liquid corrosion inhibitors.

The American Petroleum Institute (API) method for rod pumping system design became available in the mid 1960"s. Even after 30 years, questions still arise concerning its utility. This paper examines basic premises of the API method and how these affect accuracy and applicability. A comparison is made with wave equation techniques which are also widely used. It is concluded that the API method is useful and can be applied with confidence as long as underlying assumptions are not violated.

Data from field tests of a new flux-leakage/eddy-current wireline logging tool are presented. This device is used to inspect well casings in place. Images of both the inner and outer surfaces of the casing can be produced using the high resolution data provided by this tool. A real-time signal processing algorithm is available to enhance the raw data. The signal processing algorithm is described, and then several examples of applying the algorithm in different wells are given. Both conventional data presentations and images are shown.

For most wells that have to be pumped, the conventional crank-type beam pumping unit meets all specifications and is lower in price and maintenance costs. However, in recent years a new unit has become increasingly popular because it has some advantages over the conventional unit. This is the Air Balanced Beam Pumping Unit, which differs from the conventional unit in that compressed air is used as a means of counter-balancing the load on the polished rod.

It has been accepted industry practice to utilize continuous measurement in the control and optimization of production facilities, however upstream reservoir and production Engineers are challenged to make similarly important decisions based on little or no downhole data. The development of real-time well monitoring technologies for land-based applications has furthered Engineer's ability to make pro-active decisions based on continuously monitored bottomhole parameters including pressure, temperature and flow.

In June 1978, the Carbon/Oxygen (C/O) Log began aiding formation evaluation in the Gorieta reservoir of Johnson Field, a moderately porous carbonate trend in central Ector County, eight miles northwest of Odessa, Texas. Production there is from four separate reservoirs - the Grayburg - San Andres, the Holt, the Glorieta, and the Upper Penn. Until recently, Glorieta development was limited by lack of oil shows in drilling samples, by poor drillstem test performance, and by high water saturations calculated from open-hole logging packages.

The Formation Micro Scanner (FMS*) tool was introduced commercially in the United States in the Permian Basin in 1985. The tool is the latest development in a four pad, eight button dipmeter type tool, with an array of twenty seven buttons on two of the pads. On pads three and four, twenty seven resistivity curves are then processed into images. Since each image covers 2.8" of the borehole wall, in an 8" borehole 22% of the borehole is imaged with each logging pass.

Since its introduction to the oil and gas industry approximately five years ago, the consumption of line pipe in thinner than standard wall thickness has grown to the extent that now its utilization in oil and gas lines has become commonplace. Within the last two years this thin-wall concept has grown to embrace oil well casing and tubing as well. This paper will attempt to list some of the current applications of thin-wall pipe as well as the sizes and wall thicknesses available.

Previous advances in biotechnology have provided significant contributions to the oil and gas industry. Enzymes have been used for many years as low-temperature gel breakers. The previous enzyme products were non-specific mixtures of several different, non-isolated enzymes. Degradation by these systems resulted in the creation of polymeric fragments of widely varying size and damage tendencies. Recent biotechnical research has led to the identification of specific enzyme complexes to effect much improved degradation of polysaccharide polymers.

For many, their first introduction to fiber optics was the decorative lamps of the late sixties. A group of optical fibers was tied together at one end and splayed out in a fan at the other. A bright bulb at the tied end illuminated the fibers, and light emerging from the loose end made them sparkle. It created a lovely effect, but had little practical use. Fiber optic technology has come a long way from the glittering lamps of the sixties. During the seventies, the telecommunications industry began to experiment with fiber optics in telephone circuits.

Numerous types of pump off control devices have been available to producers and operators since the late 1960"s. Since that time, pump off controllers have proven themselves to be invaluable in reducing lifting costs and increasing pumping system efficiency. This technology has, in general, been applied only in cases where economic justification is assured. Sadly, marginal (or stripper) production does not justify the expense and maintenance of most controllers.

A recently developed SPC program from Nalco/ Exxon Energy Chemicals, L.P. can significantly increase control of rod pumped wells. The program is applicable to automated pump off control(POC) systems where the controllers communicate with a common host. The program was derived from a need by Amoco to more effectively monitor paraffin deposition on tubulars in deep commingled wells. These wells experienced severe paraffin deposition resulting in costly well repairs. While the treatment method was important, the lack of an effective monitoring tool was critical.

Accurate and timely information is necessary if oilproducing facilities are to be operated properly. The operation of oil-producing properties at the optimum degree of efficiency is rapidly becoming an absolute necessity in the present social, economic, and political climate. The rates and volumes of the oil production, produced water, well test, and injection water are all important parts of the required information. It is not reasonable to expect a high degree of efficiency without this information being available.

There is a generally held opinion among the users of subsurface rod pumps that those pumps built to the specifications of API, Spec 11AX, have the following characteristics: 1. Their design is excellent with little need for improvement. 2. Equal quality can be obtained from various authorized manufacturers by simply specifying dimensions and materials in broad generic terms. 3. The individual design of pump parts has little or no bearing on pump performance.

The concept of the Area Waste Management Plans (Plan) for use in a company's drilling and production operations is explained. The objective of the Plan is to improve a company's waste management performance by developing appropriate waste strategies and communicating them to the field operations personnel handling the wastes. The Plan provides a process for identifying appropriate waste management strategies in a specified area's operations. These strategies consider current regulatory requirements, company policies, economic and practical factors.

A desire to return to operations in the simpler, single string form, yet maintain multiple zone allowable, formulated by the economic squeeze was the need which created the multiple completion choke assembly. A pressure production base was established as the means of allocating production, but this type of test procedure creates an economic burden which must be eliminated when a well moves to artificial lift status.

A leak in the high pressure packing of a artificial lift system hydraulic pump has the potential of causing environmental pollution, safety hazards, loss of energy and costly clean-up. The subject of this paper is a system that prevents the product being pumped from becoming exposed to the atmosphere and surround areas. The technology to be described transfers the pressure of the product being pumped to a sacrificial barrier fluid of known characteristics. When the seals wear sufficiently to leak, only the environmentally friendly fluid leaks to the atmosphere.

Proper matching of artificial lift equipment and technology to the specific problems of specific wells and reservoirs at acceptable cost is a rather sophisticated engineering exercise. Despite our current influx of engineering talent, people fully qualified to design and oversee the best possible artificial lift installations are in short supply. And those who are fully qualified very likely have other demands on their time.

The purpose of artificial lift equipment is to do work by adding extra power to the produced fluid so that the fluid will flow to the surface. The power added lifts the produced fluid to the surface at a rate higher than the well power can provide. The power is added to the fluid by some type of downhole pump or gaslift. "Artificial Lift Efficiency" is a way to calculate how effective a particular type of lift equipment is in adding power to lift the fluid. In the literature there are many definitions of artificial lift power efficiency, but there is not one particular accepted equation.