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The Unit Operating Agreement is the contract among unit working interest owners which controls their respective functions in unitized operations. While the provisions of the operating agreement related to field wide units are generally acceptable to non-operators, there are, however, some areas of concern. The purpose of this paper is to briefly discuss some of those problem provisions.

Recognizing and cost effectively eliminating liquid loading in natural gas wells through the use of low pressure wellhead compression. The use of compression to eliminate liquid loading can be utilized in conjunction with other production methods such as soaping, siphon strings, plunger lift and beam pumping. Desireable features of low pressure natural gas compression will be highlighted with actual field cases illustrating the equipment characteristics needed for successful de-liquification of natural gas wells.

The Variable Slippage Pump

More and more interest is generated for fiberglass tubulars because of their excellent corrosion resistance and mechanical strength. The major obstacle for more extensive use of fiberglass has been the lack of recognized engineering standards that would allow the field engineer to specify fiberglass with confidence for a particular application. Recognizing this need, several API committees are at work with unusual speed and efficiency to develop product specifications for fiberglass tubulars. Specifications for low pressure line pipe were issued in 1986.

More and more interest is generated for fiberglass tubulars because of their excellent corrosion resistance and mechanical strength. The major obstacle for more extensive use of fiberglass has been the lack of recognized engineering standards that would allow the field engineer to specify fiberglass with confidence for a particular application. Recognizing this need, several API committees are at work with unusual speed and efficiency to develop product specifications for fiberglass tubulars. Specifications for low-pressure line pipe were issued in 1986.

ARC0 Oil and Gas Company has completed six drainhole wells in the Empire Abo Unit and plans to complete four more in early 1984. A drainhole well is one in which the wellbore has been deviated from vertical to horizontal with a turn radius of 20 to 30 ft. The horizontal hole extends up to 200 ft. Figure 1 illustrates an ideal drainhole completion. The increased surface area open to flow in the oil column reduces the susceptibility to gas coning as compared to conventionally completed wells. "Conventional Well" refers to a cased, vertical wellbore which has been perforated and acidized, (Fig.

ARCO Oil and Gas Company started producing the nation's first large-scale natural carbon dioxide (C02) reservoir on January 31, 1983, from the Sheep Mountain Unit located in Huerfano County, Colorado. With the installation of a 330 MMCFD capacity pipeline, completed in January 1983, this CO2 has become an important source for future enhanced recovery projects in the West Texas area. This paper describes the Sheep Mountain reservoir, including a geological history, and the current theories for CO2 creation and migration in the Dakota and Entrada formations.

The purpose of this paper is to present an objective non-technical discussion, describing and comparing surface and downhole analysis. Previous discussions of surface and downhole analysis have been offered with only casual reference to each other. Both surface and downhole analysis can play an important role in practical well analysis programs.

A Pressure Vessel Management System (PVMS) using a computer program called PVCALC has been used extensively by Conoco's Midland Division for the last two years. PVMS was originally implemented (intra-Division) to be sure that all new pressure vessels bought for the Midland Division met the ASME Code. The program has been expanded to analyze surplus equipment. Vendor designs on at least 17 new pressure vessels have been analyzed, with only 12% of the vessels meeting ASME Code on first analysis. Ten surplus pressure vessels have been analyzed with PVMS and used, saving $500,000.

Recent field tests in South Louisiana have culminated a three-year research project by Baroid. The project objective was to apply the computer expertise developed while producing Baroid's CDC (Computerized Drilling Control) units introduced in 19711 to the development of an automatic pore pressure logging system. The CDC units require crews of up to seven people. The proposed system was to require only three crew members through more reliance on the computer for data collection, analysis, and presentation.

Paraffin problems can now be controlled economically by the use of a chemical dispersant. This paper reports on the progress made thus far with the use of a new chemical dispersant, available in four forms for field application ease; the location of certain major problem areas; and the various geographical locations where these new dispersants have been effectively used. Realizing one of the problems for making products of this nature work is precise field application; this paper also presents a scientific method for determining the treating requirements for two of the forms.

As the production of oil increased, the emulsion problem increased. The companies, realizing that some better way of separating the water and oil had to be devised, installed large tanks, both wooden and steel, placing steam coils inside them. This method proved superior to the old pit system, however, it was far from perfect. Not only did the emulsion that was not treated create a disposal problem, but much of it was impossible to break down with the heat alone, consequently other methods were sought. Thus the first commercial treating chemical was used.

Paraffin is costing the crude oil producers untold millions of dollars per year. In down time, loss of production, plugged wells, lines and emulsified oil in storage tanks. This problem has been attacked in many ways and until a few years ago, the removal of such deposits was done by mechanical methods, oil producers sought the use of chemicals such as solvent and paraffin inhibitors, of which there are several chemical formulas on the market that are doing the job economically and well, if they are properly applied.

Thirty-two gas wells were incorporated into a computer program in the Greta Field, Refugio County, Texas. This computer program includes gas measurement for all 32 wells and control of 15 wells. Individual computers for each well are located at the lease metering sites. Flow volumes are recorded, and wells are controlled from a console located at the Tom O"Connor Gas Plant. Transmission of signals between computer and console is through an aerial multiconductor cable.

This paper contains a discussion of the design and operation of the electric immersion heating element as well as the results and interpretation of the field test that was conducted.

This paper describes the use and results of using expanding cement to repair casing leaks in West Central Texas. In the past, casing leaks were squeezed using Class C cement (high sulfate resistant. This would take from three to five hours and often several stages, The use of expanding cement has cut the time required for squeezing to one-half to two hours, usually requiring only one stage. This method uses the high gel-strength cement to hold its own hydrostatic pressure to give a quick shut-off to casing leaks. The weight of this cement is heavier than ordinary Class C cement.

The ever-increasing shortage and resulting higher prices of natural gas and oil make it important to conserve fuel whenever possible. One way is to remove all free water from the produced oil Stream before treating the emulsion. This paper discusses the application, design installation, operation, maintenance, trouble shooting, and corrosion protection of free-water knockouts used for this purpose.

Factors to he considered in the selection of inhibitors and treating techniques used to control downhole corrosion in gas wells are discussed with special attention to deep, hot wells. Corrosion monitoring is recognized as a complex but necessary part of any corrosion control program.

Corrosion of oil field production equipment is a serious problem which is many times not given the consideration it deserves. Every year, the oil industry pays a corrosion bill running into millions of dollars. In many cases, the fact that some of their sots can be eliminated is not realized, and others, the ravages of corrosion are not recognized. It is now possible in some cases to economically allay the reoccurring costs of maintenance of equipment, and in others to percent the actual destruction of the equipment.

A new analytical procedure is described here for predicting well performance and analyzing completion effectiveness of wells which have a significant pressure drop from turbulence. (In this discussion we use the term turbulence to describe both turbulence and all other rate dependent deviations from darcy flow such as inertial effects.) The procedure is more applicable to gas well completions but has been applied to a high-rate oil well. In particular, the new procedure should provide a powerful analytical tool in areas where most wells have high production potential.

Proper use of d-exponent data accurately predicts formation pressures while drilling in the Delaware Basin. This paper shows how this information can be used to minimize drilling costs by: 1) Proper maintenance of well control. 2) Selection of casing seats. 3) Prediction of hole stability caused by heaving shales in an underbalanced system.

Test data collected from the TTU test well plus field data will be used to show the impact of pump clearance and pumping speed on pump slippage. Pump slippage significantly increases with increased well depth due to high temperature reducing water viscosity and increased differential pressure acting across the plunger. Specifying plunger length and other recommended practices will be discussed. A procedure to design the pump clearances based on sensitivity of the various correlating parameters will be presented.

This paper serves to up-date applications and results of the Vannsystem. The Vannsystem is the process of running large casing guns on tubing for maximum completion performance. Prior papers on this system have dealt primarily with maximum differential perforating to overcome formation damage. The 3,000 plus wells completed using this technique included such applications as tight gas sands, highly unconsolidated sands, intervals of several hundred feet, formation evaluation, off-shore, injection wells, and others. Recent key applications, along with case histories, will be reviewed.

Heightened regulations and enforcement on air emissions from oil and
condensate tank batteries have many companies evaluating new technologies for capturing these vented natural gas emissions. These gas streams are a challenge to capture effectively, especially on truck loaded batteries. This talk will focus on "best in class" technologies to capture these gas streams effectively and consistently

During recent years, multiple completions have become more commonplace. This is to be expected due to the obvious economic advantages derived from producing two or more allowable while having to drill but one hole. Problems encountered in producing multiple completions, as in single completions, are usually minimal, until artificial lift is required. With the installation of lift equipment, production from zones beneath a packer can be adversely affected if the pump intake pressure is below the bubble point of the produced fluid and the gas production is not adequately vented.