The author describes factors contributing to poor water conditioning practices and the problems which have resulted.

The questions and issues surrounding sucker rod connection integrity and its effect on well failure rates has been around as long as the sucker rod itself.

Bosch Rexroth is a manufacturer of hydraulic drive systems and components including power units, cylinders, and electronic controls. The R7 pumping unit is a specially designed hydraulic artificial lift system for crude oil pumping or natural gas dewatering applications. It can be used in applications with rod loads between 15,000-35,000 lbs, and stroke lengths up to 236 inches. It consists of a hydraulic power unit, which is driven by an electric motor, and a hydraulic cylinder, which stands vertically on top of the well head. The power unit also contains an electrical control cabinet with a PLC and an operator touchscreen to input control parameters to the system. Additionally, the power unit contains a
mechanical flywheel, which is mounted directly on the shaft of the electric motor and is used to recover energy during the pumping process

Shortage of oil, rising prices and increased difficulty and expense in finding new reserves make it imperative to investigate techniques for further stimulation of wells, particularly wells with large open hole sections, or wells with poor cement jobs. With this in mind, a method was investigated that resulted in the control of the placement of stimulation fluids through the use of radioactive tracer material and Gamma ray detectors, which provided instant and continuous knowledge of the zone of entry during the entire stimulation process. This placement technique insures all zones of interest are stimulated without stimulating water bearing or other undesirable zones.

Detailed study of a field in the Slaughter area of Hockley County resulted in increased original-oil-in-place (OOIP) as compared to an earlier estimate from an internal company report (1975). An important aspect of the study was the inclusion of well logs drilled after the earlier estimate of OOIP. Log-core transforms for Compensated Neutron Logs (CNL) and Sidewall Neutron Logs (SNP) and Sonic logs were constructed. Three Old Neutron (ON) logs were normalized to improve the spatial control of the field. The normalization of the ON logs involved the correlating of the ON log data to a modern neutron log (CNL/SNP). Availability of more data made it feasible to obtain more accurate reservoir parameters for the field that was developed in 1930"s.This paper describes the methodology involved in the construction of the geologic model to calculate the net pay, average reservoir porosity, permeability and water saturation. The OOIP was calculated using the isovolume and parametric averaging methods. The OOIP was increased by two folds from the earlier estimate, but only 63% of the OOIP was movable.

For years we have known that "Long and Slow" is considered a Best Practice for rod pumped wells and that continuous running is best for ESP"s. In a perfect world we would have the ability to slow down or speed up a pump unit or ESP to match fluid inflow and to vary the speed of the up and down stroke of the rod pump system to minimize rod buckling. In reality, we design a rod pump system for 80 to 85% run time and minimize pump off pounding with a POC. Our ability to do this is often limited by pump unit or sheave size. Fluctuating production results in high fluids or cycling of the artificial lift system. For ESP's we usually adjust the operating frequency based on monthly fluid shots. The industry recently took a step toward that "Perfect World" with Adjustable Speed Drives (ASD"s).

The Upper Devonian Woodford Shale ranges from a thickness of 0 ft to 300 ft and is found at depths of 7,000 ft to 18,000 ft in the Delaware Basin. The Woodford is thermally mature over its entire extent in New Mexico: In the deeper parts of the Delaware Basin it is in the thermogenic gas and condensate window; on the Northwest Shelf and where present on the Central Basin Platform it is in the oil window. Southeastern New Mexico is subdivided into Regions I, II and III based on the intensity of the fracture networks, thermal maturity and Total Organic Carbon (TOC) (Comer 2005). Miller's (2010) gas shales ranking scorecard used parameters like total organic carbon, vitrinite reflectance, shale thickness, gas-filled porosity, clay content, quartz content, fluid compatibility, natural fracture intensity, tectonic stress and reservoir pressure gradient. The range of the scale of ranking is 0 to 100 points and for reference, the Barnett has 73 points. The better the total points, the better are the prospects of finding shale gas. Each of the regions (Regions I, II and III) were ranked for the prospects of shale gas using Miller's (2010) ranking scorecard and assigned a score of 68, 66 and 48 respectively. The results showed that Region I and II have better chances of finding shale gas. Finally an assessment was made to quantify the volumes of oil and gas in-place using Comer's (2005) Hydrogen mass balance method. The estimated volumes were 36 billion barrels of original oil in-place and 44.5 trillion cubic feet of original gas in-place (New Mexico) in comparison to 119 billion barrels of original oil in-place and 230 trillion cubic feet of gas in-place in the Woodford for the entire Permian Basin (Texas & New Mexico) (Figure 3). The assessment confirms that Woodford shale is a major unconventional source of both oil & gas in New Mexico.

One of the most helpful and convenient aids in the successful application of conventional beam pumping units is the American Petroleum Institute bulletin, 11 L-3, "SUCKER ROD PUMPING SYSTEM DESIGN BOOK". Expanding the work of Sucker Rod Pumping Research Inc. and the Midwest Research Institute, the API produced this set of tables (11 L3) containing literally thousands of different precalculated pumping options, or modes, generated by using a model of the wave equation applied to sucker rod pumping when using conventional beam units. These API tables have been widely accepted, and though certain sections have been questioned, and in some cases revised - in general, they have made a substantial contribution to the petroleum industry in facilitating the application of conventional pumping units. According to these tables, there are twenty API approved sucker rod sizes, eighteen approved stroke lengths, and ten different API plunger diameters. Thus, in lifting a given amount of fluid from a particular depth, with a conventional pumping unit, theoretically there could be some 3600 beam and sucker rod system options, or pumping modes, for a single, artificial lift application - not considering variation in pumping speed.

Reservoir simulation has typically been applied to only the larger and more complicated reservoirs. The cost of performing such studies in a Unix/Workstation environment is high and most fields are not analyzed using reservoir simulation. Highpower inexpensive PCs, and software with a powerful, user-friendly interface that does not require a simulation expert has changed the economics of performing such studies to such an extent that engineers and geologists are now using PC-based reservoir simulation to evaluate exploration plays on a teal-time basis. This paper documents the process and results of a study that involved mapping, gridding, geostatistics and reservoir simulation of an exploration prospect while the drilling rig was on-site. The paper demonstrates the feasibility of using PC-based reservoir simulation as a routine part of reservoir management, beginning with the exploration well.

The openhole drillstem test (DST) has changed little in the last 30 years; however, pressure-transient analysis recently has made significant advancements. Modern electromagnetic telemetry systems are the basis for an economical method of transmitting pressure and temperature readings in real time." Improvements in information technology now allow advanced on-site analysis. This paper provides an overview of an openhole test, describes the components used during real-time analysis, and discusses the case history for a real-time job in Andrews County, TX.

The experience gained from many years of computerized analysis of dynamometer records combined with very powerful portable computers, advanced modeling software, advanced graphical user interface and wireless datab acquisition systems allow the visualization of the operation of the rod pump in real time. The operator directly observes and determines at a glance whether the pumping system is operating efficiently or requires modification or remedial intervention. The majority of the analysis is performed automatically and does not require evaluation of numerical results by the user. When unusual conditions are observed the user has access to advanced tools that facilitate detailed diagnostic analysis.

The concept of predictive modeling for "What if?" and contingency analysis is well established for electric power dispatching. We are currently completing the first such system for gas pipeline network dispatching. The model accounts for fully transient flow of gas through pipelines and equipment. Based on flow forecasts, 16 hour predictions of pressure, horsepower, and fuel are made. The system continually tracks the SCADA data base so that the linepack distribution is current. In addition to answering "What if?" questions, the system supports risk analysis, leak detection, and strategy evaluation. The model can be used for pack and draft analysis, compressor fuel optimization, and operator training.

Sucker rods performance greatly impacts fluid lifting efficiency, and rod failure lead to lost production. Therefore, proper attention to the condition of new and used rod strings can assure optimum operating efficiency and reduce total production costs. The performance of the string depends on the proper integrity of each individual rod. These rods are subjected to severe operational conditions and down hole conditions such as corrosion, cyclic loading, and stresses which can ultimately lead to material break down. It is of utmost importance to investigate the condition of new and used rods to ensure the absence of stress raisers and manufacturing imperfections. Nondestructive testing (NDT) is used in this application. It will be our intent to show pictures of what defects we have found in new and used sucker rods. And not to point a finger at any rod manufacture. We will evaluate both manufacturing and service induced flaws in sucker rods and couplings. That would cause premature rod failures and thereby avoiding the time and labor costs associated with work-over operations.

Balancing injection-withdrawal ratio on a pattern basis is essential in optimizing tertiary recovery projects, where high lease expenses tend to marginalize even the best of candidates. Advances in reservoir modeling techniques provide increasingly reliable predictions of long term field-wide production response; however, a gap frequently exists in supplying routine or short term individual well forecasts. This paper describes a simple allocation technique utilizing a modified version of Darcy's equation for linear flow within the setting of a field-wide pattern network. Generated factors allocate actual injection to offset production, calculating idealized production volumes on a gross reservoir barrel basis for comparison to actual production to influence uniform injection-withdrawal. In other words, a check and balance system to assist in guiding operations. Developed over the past several years for use in the SACROC Unit in West Texas, tailoring is possible for other secondary/tertiary recovery projects given field specific conditions.

Operating electric submersible pumps in a CO2 flood is challenging and requires applying new engineering and operational resources to be successful. Extremely high GLR"s, radically changing bottom hole pressures and changing fluid densities require more than just conventional methods for operating and troubleshooting ESP"s. An integrated control system was used to troubleshoot well conditions that consist of high concentrations of CO2. Accurate bottom hole pressure, temperature and vibration information was collected and used to determine actual well conditions and make decisions based on real data.This application decreases the "guess work" previously used in determining bottom hole conditions and increases the effectiveness of decision making to correct problems. This paper is a continuation of work efforts that were started and discussed in last year's SWPSC.

By arranging the geometry of the beam type oilfield pumping unit as a non-symmetrical front-mounted lever system, it is possible, in most cases to fit more closely the counterbalance torque pattern to the well load torque pattern, with significant reductions in peaks. This system results in a relatively uniform loading of both prime mover and gear reducer; the loading in turn allows the operator to handle many applications with smaller equipment and reduced first cost.

The technology associated with the use of carbon dioxide as a component of oilfield stimulation fluids has evolved dramatically since its introduction in the early 1960's. Technology improvements in the mechanical, chemical, and applications areas will be discussed herein. This paper will be introduced with a brief review of the chemical and physical properties of carbon dioxide which are the basis for the utilization of CO2, in the stimulation industry. The introduction will be followed by a discussion of mechanical advances in CO, pumping equipment, pressure maintenance devices, heaters, fluid viscosity measurement, flow monitoring instrumentation and safety equipment. Next, chemical developments such as CO,-compatible acid, water and alcohol gellants, dispersants, vapor phase stabilizers and crosslinkers will be traced. Finally, stimulation applications of CO2 will be described. These applications have multiplied from acid and hydraulic fracturing fluids energized by CO2 as a minor commingled component for rapid removal of mud, silts, fines, water blocks and emulsions, through miscible hydrocarbon treatments, to dispersions, "foams" and crosslinked alcoholic fracturing fluids where CO2 is the major component.

MWD services have been commercially available for over ten years. The most entrenched application is that of directional services, where conventional methods such as wireline steering have all but been obsoleted. The only real advances in this application have been those influenced by software changes and data rate improvements. For example, faster tool face update rates while steering are now possible. A relatively recent sensor is one that provides weight on bit and torque in real time. The currently intended applications are estimation of bit wear and bearing failure. A drilling model is used to estimate shear strengths of the rock, although the model currently appears to be limited to shales only. The resulting Mechanical Efficiency Log is used for a variety of interpretations. An augmentation of the RLL service is now available whereby the recorded log may be retrieved on a wireline by stabbing with a "wet" connector upon demand. In the interests of brevity, neither this nor the MEL service will be discussed here. The other recent sensors/services are the EWRR and CN0SM, both described more fully below.

From the earliest days of West Texas drilling, produced brines have been readily available. Drillers quickly realized, even in the early days, the advantages to be gained from drilling with clear brine. Today, good quality brine is conveniently available to most parts of the Permian Basin at a delivered cost of 25 cents to 50 cents per barrel. The advantages of using clear brine as a drilling fluid have been adequately documented. The more obvious advantages are: (1) improved penetration rate with a solids-free fluid as compared to a typical drilling mud; (2) clear fluid with a density of up to 10.0 ppg is available when needed for pressure balance; (3) the natural tendency of brine to "pickle" or inhibit the swelling of shaley formations, thus protecting production zones and hole condition in general; and (4) all these at a relatively low unit cost compared to conventionally formulated drilling fluids.

In recent years the development of refractory materials has proceeded at a much faster rate than the ability of industry to utilize them effectively. This paper will discuss in detail some of the more interesting of these compounds, their potential for the petroleum industry and a process by which they may be uniformly applied to the surface of any object. Radio frequency sputtering is the name of the process and it is the intent of this paper to give sufficient detail as to the basic description and parameters of this process to enable the reader to implement it with a reasonable degree of effort. Results are cited that pertain to field problems.

Use of liquefied gases as fracture fluids has been a commercially available service for more than a year and both results and experience have helped dictate new developments and define candidate reservoirs. Designed originally for gas well stimulation, the new service uses a fluid made up of liquefied CO2, LPG and methyl alcohol. The liquefied gases are mixed in such a proportion that they remain a liquid and behave as a liquid as long as they are under adequate pressure and below the critical temperature of the mixture. When they are heated above their critical temperature in the reservoir and pressure released, the liquid reverts to a gas. This results in extremely rapid clean-up and minimizes problems of water sensitivity and liquid retention damage. In practice, the liquefied gases are mixed in varying proportions depending on reservoir temperature. For each well, the proportion is designed to provide a mixture that will have a critical temperature about 15% below the reservoir temperature. Since the mixture is not an effective frac fluid in itself, a gelling agent in methyl alcohol is added as a third component to provide the desired properties of viscosity, low leak-off or fluid loss control, low friction pressures, and good prop-carrying ability. In a stimulation treatment, the liquefied gases are mixed in proper proportion on location and pumped to the wellhead. The gelled alcohol and prop are mixed using a special pressurized blender and pumped to the wellhead where they mix with the liquefied gas mixture to produce a uniform prop-laden frac fluid. Not only is it necessary to design the liquefied gas mixture to have the proper critical temperature for each well, but it is also necessary to design the methyl alcohol gel to provide the desired frac fluid properties to the final fluid for each well. Properties of the final fluid are determined from conventional fracture design calculations. (Although addition of the gelled alcohol to the liquefied gases increases the critical temperature of the mixture, laboratory data indicate that this increase is more than offset by designing the liquefied gas mixture to have a critical temperature 15% below reservoir temperature. In low-temperature wells, design is based on vapor pressure of the liquefied gas mixture as compared to reservoir pressure.)

This paper discusses the latest equipment and software developments in wellsite drilling monitor systems. Included is a discussion of data collection and analysis by on-site computer. Specific emphasis on data analysis for drilling optimization and pressure detection in hard rocks is presented. New analytical tools, such as mud temperature and conductivity logging, are discussed, An economic analysis of data collection units gives the operator a basis for judging the merits of available services.

A sound velocity sensor is described as a means for detecting interfaces between different hydrocarbons in products and crude oil pipelines. Temperature and pressure influences are described as systematic error sources that are amenable to automatic compensation by a microprocessor. The utility of the sonic technique is assessed for detecting difficult interfaces between hydrocarbons of similar API gravities and for those interfaces where substantially different gravities prevail. A new development involving a combination sonic interface detector and sonic flowmeter is also discussed.

This paper discusses the development and use of polyelectrolyte's as broad spectrum coagulant aids and/or coagulants in the clarification of oil field waters.

Many papers have emphasized the problems of obtaining efficient mud displacement by cement, causing channels, annular gas flow and other problems. Mud displacement in liner cementing is more difficult than in full-string cementing because of several factors. Some suggestions for obtaining better results in liner cementing through, the use of newly-developed rotation equipment are presented in this paper. Tools designed for these types of jobs are shown and recommended procedures given.