Paraffin formation has been a problem for many oil producers. Current technology for alleviating the problem of paraffin build up consists of: (1) mechanical removal, (2) removal with hot oil or other solvents, and (3) treating the wellbore with a paraffin dispersant or inhibitor. This paper will discuss the application of a new form of paraffin inhibitor and a novel technique for introducing the paraffin inhibitor into the producing formation. The study was conducted in the Dean Formation, Ackerly Dean Unit (ADU), Dawson County, Texas.

Oil Operators in Southeast New Mexico have been very successful in producing wells dual completed in both the Blinebry and Paddock formations. One area of contention, however, has been the mineral saturation in the commingled brine and the incompatibility of the various minerals in the two produced brines. Liquid scale inhibitors, applied conventionally during the fracture stimulation of each zone have not been successful in preventing formation of calcium carbonate and calcium sulfate scales after the wells have been placed on production. This paper details several successful applications of a novel, solid scale inhibitor that is applied with the proppant during the fracturing process. The application of this inhibitor has provided the Operator with maximum production and minimal remedial workover expense through long-term inhibition of calcium scales.

The purpose of a gas separator is to separate free gas from produced fluid before the fluid enters the intake of an electric submersible pump (ESP). If free gas is allowed to enter the ESP, it tends to cause the ESP to cycle, resulting in additional pump and motor wear and eventual contamination of the motor oil with wellbore fluids. Two types of gas separators are commonly available, the reverse flow separator and the rotary separator. This paper summarizes a recent field test in which the performance of the rotary gas separator was compared to that of a reverse flow separator under similar conditions in the same well. This field test was done on a low volume well under waterflood. An ESP was run in this well because a beam lift would interfere with the landowner's irrigation equipment. The original ESP, which was run with a standard reverse flow separator, could not pump the fluid level down because excessive gas caused the unit to cycle on and off. Three cases were studied. The first two cases consisted of running two identical 400 BPD ESPs, each one for a period of several months. The first ESP was equipped with a standard reverse flow separator and the second was equipped with a rotary gas separator. In the third case, a 280 BPD ESP equipped with a rotary gas separator was studied. It was necessary to run this ESP because the originally sized 400 BPD ESP became oversized once the effect of gas cycling was removed due to the rotary gas separator.

Commercial Measurement While Drilling systems have now been available for over ten years. A broad range of capabilities have been developed, albeit at significant cost. Development has primarily been driven by technology availability. The market for MWD services has been primarily limited by capability, supply and cost. MWD technology has now matured to the point where it is possible to offer significantly more capability than may be required in a given situation. Current MWD applications can be categorized as directional drilling, drilling efficiency, non-reservoir formation evaluation, and reservoir evaluation. The basic data requirements of these applications are sometimes complementary, however the cost of providing a system to cover all applications is prohibitive for the majority of wells. MWD is a technological development impacting several other wellsite services. The most significant of these are Drilling Equipment, Mudlogging and Wireline Logging. MWD cannot fully supplant any of these services, and must coexist alongside them all. Thus, any projection of the future role of MWD must look at the current and future interaction between all these services. Analyzing the inherent capabilities and limitations of each service provides an insight into their intrinsic benefits and value. Projecting likely future developments, it is concluded that MWD services will evolve to offer a broad range of applications solutions. These will focus on the inherent unique capability of MWD systems to provide downhole information as the well is being drilled. This should result in MWD services becoming an economically viable option for a wide range of wells.

This paper illustrates the wide use of PD meters and the growth of their use, particularly in Lease Automatic Custody operations. Furthermore, it discusses many of the basic principles of efficient meter operation, namely installation, proving meter accuracy, maintenance requirements and sampling. Various factors which influence accurate measurement are discussed, as well as different types of meter proving devices.

Evaluation of artificial lift requirements and selection of appropriate lift equipment for an oilwell must take into account the well inflow performance under anticipated producing bottom hole conditions. Controlled well test at these conditions will generate the necessary inflow performance data for this purpose. This paper describes a portable Production Test Unit and related well equipment which permits multi-rate production testing for the purpose of developing IPR data. Description of the Hydraulic Jet Pumping System used and examples of test procedures are included.

A new portable system has been developed for both the acquisition of dynamometer data and the subsequent analysis of that data. This equipment may also be used to determine acoustic fluid levels and obtain surface acoustic pressure-transient data. This paper contains a brief description of the hardware system, how the data is analyzed, and how the data is interpreted to obtain the diagnostic bottom hole dynamometer cards and surface torque analysis. Two features of the system include a new load cell concept and a displacement transducer. The loads are taken with a normal strain gauge which can be of the cable transducer type that is fastened to one of the bridle cables or of the conventional horseshoe type transducer that is placed on the polished rod below the polished rod clamp. The displacements are obtained by recording acceleration from an accelerometer contained in the selected transducer, which is later integrated twice to obtain displacement at the surface. An appropriate method is included in the software to evaluate the constants of integration which result from this integration. Motor current is also recorded when the determination of counter balance is desired. Conventional methods are used to calculate the bottom hole card. The operation of the equipment will not be described here, that may be learned from the operators manual associated with the equipment, rather this paper will deal with how the equipment works and how it may be effectively used.

A new portable system has been developed for both the acquisition of dynamometer data and the subsequent analysis of that data. This equipment may also be used to determine acoustic fluid levels and obtain surface acoustic pressure-transient data. This paper contains a brief description of the hardware system, how the data is analyzed, and how the data is interpreted to obtain the diagnostic bottom hole dynamometer cards and surface torque analysis. Two features of the system include a new load cell concept and a displacement transducer. The loads are taken with a normal strain gauge which can be of the cable transducer type that is fastened to one of the bridle cables or of the conventional horseshoe type transducer that is placed on the polished rod below the polished rod clamp. The displacements are obtained by recording acceleration from an accelerometer contained in the selected transducer, which is later integrated twice to obtain displacement at the surface. An appropriate method is included in the software to evaluate the constants of integration which result from this integration. Motor current is also recorded when the determination of counter balance is desired. Conventional methods are used to calculate the bottom hole card. The operation of the equipment will not be described here, that may be learned from the operators manual associated with the equipment, rather this paper will deal with how the equipment works and how it may be effectively used.

The purpose of this paper is to present specific recommendations for an adequate power oil settling system which will furnish clean power oil for hydraulic bottom hole pumping installations. The design herein given represents the consensus of operating personnel and service personnel and is judged to be a very practical answer when considering adequacy and cost.

Early in 1970 all available pre-1970 subsurface equipment failure data contained in the data banks of Atlantic Richfield's Equipment Performance System were analyzed. Assuming no changes in operations or in failure patterns, it was predicted that in the year 1970: 1. Corrosion and/or equipment mishandling would be the cause of 73% of all subsurfaced equipment failures. 2. Rod failures would account for about 40% of all subsurface failures. 3. About 60% of all rod failures would be rod body and about 40% pin or coupling failures. Supervisory production personnel realized that considerable improvements in profitability could be achieved by reducing handling-caused failures and by implementing effective corrosion control programs. They also realized that attempts to control corrosion and handling-caused failures have to be initiated and carried out by personnel responsible for day-to-day operations and that these individuals should, therefore, have the knowledge and the tools to carry out this task of subsurface failure control. This task requires the necessary knowledge to determine causes of failures, available courses of action, and the economic feasibility of carrying out these courses of action. At the request of these production personnel, a short course was prepared to satisfy these needs. The subject matter was slanted toward rod failure control. It was reasoned that it was economically practical to avoid rod handling-caused failures and that corrosion control of rod failures would benefit other items of subsurface and surface equipment. This presentation condenses the short course. In sharing our approach with the oil industry, we hope for comments and suggestions to improve this approach.

To date, standards proposed for filament-wound glass resin line pipe used by the petroleum industry generally define only mechanical tests for structural strength. It will be explained why this data alone can be very misleading as a basis for comparison. Other parameters, such as chemical resistance, actual pressure ratings, safety factors, ultraviolet sensitivity, life of plasticized liners, and long term flow stability, are felt to be far more meaningful and realistic for evaluation of the product from the user's standpoint. This paper will present a composite set of practical methods suitable for determining the basic properties of the product for the petroleum industry. Comparative actual test data will be included. In conclusion, a chart to establish practical evaluation ratings will be submitted. The use of this chart will enable the user to assess filament-wound glass-resin line pipe for his application, with a high degree of confidence.

This paper is a general explanation of the financial mechanics of an oil and gas economic project analysis. Emphasis is placed on the meanings and usage of certain financial terms and ratios such as interest rate, present value, future value, discount rate, internal rate of return, payout period and return on investment.

In 1973, a decision was reached to make a comprehensive joint geological and engineering study of the North McElroy Unit. It was hoped that the combined efforts would result in a more practical study to assist in the current waterflood operations. The objectives of this study were to (1) determine the different lithologies within the unitized interval and their associated physical properties; (2) establish reliable correlations and construct meaningful structure maps; (3) define the most efficient completion and production techniques; and (4) incorporate a more efficient water-injection program.

A procedure to optimize drilling programs is presented from a practical standpoint. The concept of a control well based on offset well data, using a cost per foot approach is discussed. Once the control-well and proposed-well data have been determined, a systematic analysis of the drilling variables is carried out. This analysis is concerned with the drilling hydraulics, mud properties, bit type, bit weight, and rotary speed. The final product is a well program which includes a summary of the proposed hydraulics, mud system, bit selection and operating conditions. In a final analysis, proposed drilling costs are compared with costs for the control well, and the proposed cost savings is determined.

Agnew" has proposed that temperature be utilized as a method for obtaining knowledge of the portion of a reservoir which has actually been stimulated. This particular method of evaluating frac and acid treatments has been utilized for several years. Additional evidence for the use of radioactive materials with temperature has recently led to the utilization of techniques involving the use of RA materials in conjunction with temperature, which lends a more quantitative perspective to treatment design and interpretation. This is particularly true when the combined techniques are used in conjunction with selective staging of fracturing and acidizing treatments.

In secondary or tertiary recovery projects fluids are injected into the rock formations to sweep residual hydrocarbons to producing wells. To optimize this operation the fluids must be injected at specified rates into the desired depth intervals. Therefore, injection profiles are run to determine the injection rates as a function of depth. Although temperature and noise logs can provide some qualitative data, spinner surveys or radioactive (abbreviated r/a) tracer logs are run if quantitative results are desired. At the present time by far the most popular method in use is the downhole radioactive tracer ejection method. The objective of this paper is to review the basic principles underlying this technique.

Qualitative interpretation of drill stem test (DST) pressure-time charts often is more of an art than a science. However, logical and efficient interpretation can be easily accomplished by understanding the basic factors involved in producing a chart. No two DST charts are exactly the same, and thus the guidelines given in this paper are designed to be general in nature. With knowledge of the basic DST shapes and forms in mind, even complicated charts can be broken into components and satisfactorily interpreted. A DST is a temporary completion of an interval within a well to help determine as much useful reservoir information as possible about the interval. The fluids recovered from a DST help describe the fluid type available from the reservoir and how well it may flow. The pressure-time chart is a valuable record of the test events and serves to validate the test results. At the wellsite, a properly interpreted DST chart also can give an indication of important reservoir parameters, such as productivity, permeability, pressure, and wellbore damage. In addition, determination of reservoir characteristics such as depletion, supercharge, permeability anomalies, and multiple zones often is possible when the chart interpretation is coupled with information such as reservoir geology. Finally, the quantitative pressure-time DST data can be analyzed using standard industry pressure transient analysis methods. These can yield valid numerical approximations of important reservoir parameters, and further support the chart interpretation. Quantitative analysis will not be covered in this paper.

This paper presents a methodology for evaluating waterflood performance on a pattem-bypattern
basis to identify wells that may benefit from some type of intervention or remediation. We
developed this approach to have a rapid screening method to analyze the commonly available data from
a waterflood and maximize the amount of useful information that can be determined from these data.
We calculate permeability and the variation in skin factor at the injector with time. We also calculate
average reservoir pressure, saturation and net voidage within each pattern as a function of time.
Diagnostic plots and maps show regions of high and low reservoir pressure, areas of poor sweep efficiency and the locations and types of various conformance problems. We have implemented the technique described here in a spreadsheet program on a PC. We also use a mapping software package to visualize and present the results of the analysis. We show how to calculate skin factor at injection wells and average reservoir pressure as a function of time on a pattemby- pattern basis. We also describe several diagnostic plots and maps to visualize and evaluate the waterflood performance. The data required for this analysis consists primarily of data that is gathered during the normal course of water-flood operations. We use the following data in our analysis. 1. Historical monthly production volumes of oil, water and gas. 2. Historical monthly water injection volumes and pressures for each injection well. 3. Average reservoir pressure and water saturation at the beginning of the analysis (either at the start of primary production or at the beginning of the waterflood). 4. Net pay and porosity distribution, preferably on a pattern-by-pattern basis. 5. The x-y location of each well and, preferably, information on how each well is completed including tubulars, perforations and stimulation.

The Kelly Snyder field is located in Scurry County, Texas, as shown on Fig. 1. This field is one of the major oil reservoirs in the United States. After discovery in 1948, the field was produced by solution gas drive until 1954 when a recommendation by the Scurry Area Canyon Reef Operators" Committee was implemented. The recommendation was to install a centerline water injection program to restore and maintain reservoir pressure above the bubble point. In March 1953 the SACROC Unit was formed and the proposed injection program was started in September 1954. Although this water injection program worked quite well, SACROC owners continued to look for ways to further improve recovery from the reservoir. In 1968, after careful study of several possible miscible displacement processes, a SACROC reservoir engineering committee recommended a miscible carbon dioxide injection program for the Unit to increase the ultimate recovery from the reservoir. The next three years were required to prepare for the carbon dioxide injection. The field was divided into 202 inverted nine-spot pattern areas and three phase areas which would be processed with CO2 on a separate time schedule consistent with the CO2 supply, as shown in Fig. 2. To commence injection it was necessary to install compression facilities and a CO, pipeline to transport 200,000 MCF/D of CO2 from several extraction plants in the Val Verde Basin area of southwest Texas and to prepare the Phase I area for injection by installing a field injection system, exposing the entire reef in the producers, and preparing the pattern injectors for injection. With the work completed, CO,injection began in January 1972. Downhole injection surveys were run frequently during the early life of the project, and poor profile coverage was discovered in many of the injectors. The problem became very critical when CO, breakthrough occurred during June 1972, more than a year before the CO2 removal facilities were complete, requiring curtailment of production. It became evident that correction of these poor profiles was necessary to avoid cycling the expensive CO2 and to avoid further production curtailments due to CO2 breakthrough. Since several methods are available for improving injection well profiles, the Unit Operator tested and evaluated several different methods. Open-hole packers were installed in several wells, but frequent failures occurred due to packer movement or CO, permeation of the packer rubber. Several types of polymer profile improvement jobs were performed with little success. The only control method which has proven to be consistently effective for controlling downhole injection profiles is the installation of a liner across the reef, followed by the installation of downhole flow control equipment.

Fluid slippage is defined as the fluid that leaks past a metal plunger during the upstroke of a down-hole, rod-drawn, positive displacement pump. American Petroleum Specification 11AX covers this type of pump which is used in approximately 90% of artificially lifted wells. This paper will present the first part of the results of a continuing research project covering the theoretical analysis and laboratory testing of pump slippage. The goal of this project is to present a mathematical model which will accurately represent the actual down-hole slippage for this class of pump. The current results should be useful to operators for selection of clearances between metal plungers and barrels. In the review of literature many of the clearances and differential pressures were lower than what is normally experienced in light oil operations. Tested clearances that were reported in the literature were 0.007" or lower. This investigation will evaluate some new ground looking at larger clearances and higher differential pressures.

The author will review the current status of a complete new approach is well servicing that includes: 1) A remotely operated robotic-automatic well services rig wherein there is no operating personnel within 100 feet of the wellbore. 2) An integrated system for making up tubing as well as the two element rod connection to absolute computer precision. 3) An integrated system for over the well electronic inspection systems of tubing and rods.

In the past few years there have been a number of software programs developed to process open hole wireline log data on personal computers. The majority require a thorough knowledge of program documentation to obtain the maximum benefit. When this is combined with the overall reluctance among many users to read documentation, the end result is a less than optimum utilization of processing power. The Microsoft Windows* operating environment for IBM compatible computers was created with the user's needs in the forefront by utilizing the concept of a "visual interface". Programs run under this environment can be executed with a minimum of keystrokes by using a mouse and pull down menus. All options are generally displayed to the user, and a minimum of program knowledge is required to execute an application in this system. To date, though, little use has been made of the Microsoft Windows operating environment in the log analysis software arena. To take advantage of the speed and ease of use, a popular minicomputer-based field log analysis program has been modified to function in the Windows environment. The Quick Log Analysis (QLA)" program is designed to accept the full range of wireline inputs available on the market. The Windows shell allows the user to run the program with a minimum of effort and a minimum of documentation. In addition, the Windows environment allows the user to integrate log graphics, cross-plots, reports, and text into a single document. The end result is a user-friendly log analysis program with powerful capabilities.

In these times of low oil prices and increasing operating costs, we at Shell NorthStar in Baker, MT, have been searching for ways to reduce costs and at the same time reduce failures. We have been successful in failure reduction caused by corrosion. But now, we needed a way of reducing rod loads to reduce rod failures and still pump the necessary amounts of fluid to maintain production. Our pump depths range from 8200" in the Little Beaver field to 9100" in the Pine unit; average production is 40 BOPD and 250 BWPD. Gas interference had not been a problem until we started drilling horizontal wells. This problem was addressed with the use of a ring valve assembly. After discussions with Rod Johnson (Rig Management Team leader), Doug Kaufman (Dresser Oil ToolsTM District manger), the RCFA team and several people in Altura field in West Texas, we came up with several ideas. We could run a shorter plunger, run a loose fit plunger (.007 clearance instead of .003) or take a closer look at a "vortex" standing valve we learned of at a recent school.

Sucker Rods, the prime purpose of which is to impart the reciprocating motion and power of the end of the walking beam to the sub-surface pump, are such a simple piece of apparatus that it might seem nothing much could be done to improve them. However, much has been and is being done to make their proper care and use better understood, to obtain a more accurate understanding of the actual loads imposed upon them, and to improve the joint design, the rod materials and the manufacturing techniques. It is the purpose of this paper to review what has been done and what is now being done along these lines with a belief that an understanding of these problems will lead to a better use and consequently, a more economic life of this vital link in the oil well pumping mechanism.

The techniques involved in the completion of a well, with regard to cementing operations, vary with areas and with regard to cementing operations, vary with areas and operators. Certain procedures are, however, looked upon as being most suitable for particular applications and often certain cementing slurry components have been found to give better performance in one of the two major cementing operations: primary cementing and squeeze cementing. A resume of proper cementing techniques is presented which will include flow characteristics of cementing slurries, effect of turbulent flow velocities on mud removal, effectiveness of chemical washes and the use of cementing plugs. The application of relatively new cementing practices using various low fluid loss slurries will be discussed from the standpoint of both primary and squeeze cementing and a resume given on results obtained while using these techniques.