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With the evolution of design and evaluation software for Electric Submersible Pump (ESP) systems over the last 25+ years, most of the development and emphasis has been on ESP design, or sizing. All of the ESP manufacturers have, at one time or another, been involved in internal development of ESP sizing software and there have also been several third party companies who have developed similar programs. This paper will introduce the expansion of a design and sizing software program into a tool, which can be utilized for time variable modeling and simulation.

This paper discusses two steam injection methods which are currently being used by the oil industry: steam drive and steam stimulation. Each method has inherent advantages and disadvantages. Variations and/or combinations of these methods have been used to utilize the advantages of both processes.

Failures in the sucker rod industry can be costly and time consuming. A thorough understanding of the critical factors affecting the overall reliability of steel is important to address these failures. Sucker rod manufacturing involves a lot of processes from different industries. The manufacturing and servicing of steel sucker rods involves a chain of processes starting with the steel mills, sucker rod manufacturer and eventually goes to the end user. There are a lot of critical factors involved in every step of the process before the product goes down hole.

Multiple zone WAG injection techniques have changed little over the years, relying on side-pocket mandrel / injection valve technology to accomplish injection fluid diversion to target zones. These systems rely on mechanical injection valves to disperse the injected fluid. A new technique has been put into use that both simplifies the process and provides increased reliability by eliminating mechanically operated injection valves. Side-pocket mandrel injection control assemblies have been replaced with new reservoir access mandrel systems.

Carbonate formations are predominate in the Permian Basin and as such are commonly stimulated with acids. Success of an acid treatment is dependent on knowledge of the reservoir, design techniques and execution; and emphasis on obtaining good zone coverage. In addition, effectiveness is very dependent on how many times a well has been acidized and with what kind of acid. Case histories of acid stimulation, with production results, are presented on a new technique for stimulating the San Andres dolomite.

A great many carbonates are stimulated successfully utilizing acid fracturing techniques. There are several models in the industry, which will give relative comparisons of fluid performances under varying reservoir conditions. These are only good as design tools when validated. However, a great deal of laboratory time is spent testing rocks and fluids for reactivity, diffusivity and leak-off to provide the values for these models.

Fracture acidizing of carbonates has yielded increases in production in many areas. But depending upon the rock strength and the reservoir closure pressure this may be lower than expected. Also, as a result of closure and rock strength, production may decline at a higher rate than after a proppant fracture treatment. Laboratory results are presented describing the effect on the strength (Softening) of a dolomite and limestone after exposure to various acid systems.

A stimulation treatment of water input wells in the massive San Andres limestone has shown the benefits that can be expected with the inclusion of nitrogen in the treatment followed by the use of nitrogen for displacement to the formation and the subsequent backflow. The San Andres is interspersed with water zones and the multiphase system helps prevent the fracturing of the formation due to gas compressibility and carefully controlled injection rates.

A significant quantity of gas reserves exists in deep, hot reservoirs such as the Ellenburger in West Texas.

Coreflow studies, X-ray diffraction, and a variety of other investigative techniques have been used in the study of the design for stimulation fluids for a number of years. Recently, the concern for the design of non-damaging stimulation fluids to treat "problem", well-consolidated, low-permeability low-porosity sandstone reservoirs has heightened. A typical example of a problem sandstone in the Pennsylvanian age group is the overall Morrow sand. The Morrow is considered to be in southeastern New Mexico, the Texas Panhandle, the Oklahoma Panhandle, and west-central Oklahoma at varying depths.

Stimulation results from acid treatments of carbonate reservoirs are generally Limited by the extent of live acid penetration, which is determined by the rate of acid spending and fluid-loss. In recently ears, the effort to control acid leakoff and reduce the rate of spending has caused the industry to focus on developing gelled acid systems. Numerous gelling agents have been used, including natural gum, biopolymers, synthetic polymers and surfactants.

The object of this paper is to discuss the most widely used stimulation techniques currently being employed in the Austin Chalk Formation in South Texas. Although this trend has been explored for years and continues to be one of the most active in the country, there remains a difference of opinion over how to effectively stimulate this reservoir. Several schools of thought regarding types of fluids, additives, and general treating techniques will be examined.

Crude oil volume may be lost from a storage tank in the form of vapor and/or gas known as vaporization. This loss of well bore volume, which is not recoverable, is normally expelled to atmosphere. The prime question to the producer of crude oil, is what are the economics of recovering the stock tank vapor? The principles of fluid vaporization are based upon the fundamental laws of physics and will not be fully discussed at this time.

With a significant oil-price drop drilling programs are stopped and marginal wells are abandoned. Production must be continued with minimum down-time if an oil company is to stay profitable. One low-cost way to do this is to stop lightning damage.
Tank battery protection is the highest priority. Fiber glass tanks and explosive gases have made this a major challenge. Lightning collection has never been truly successful. Charge transfer systems (CTS) have prevented lightning strikes with nearly 100% elimination of damage. The particulars of CTS are discussed.

What is "stray current" and can it cause corrosion of my downhole equipment? Stray current, both DC and AC, is
known to cause corrosion of steel in contact with the earth. Phenomena which cause such corrosion, circumstances
conducive to corrosion by stray current, and practices for preventing stray current corrosion of pipelines and well
casings are fairly well understood and accepted. Anecdotal reports of stray current causing corrosion of structures
NOT in direct contact with the earth also abound.

Many dually completed oil wells are flowing and may be expected to continue flowing for many years. The flowing life of other dual oil wells is relatively short for one or both pays. Some dual oil wells never flow and require artificial lifting equipment at the time of completion. Pumping equipment that would lift well fluids separately and simultaneously from dual wells was developed in 1947.
This pumping equipment was developed with two purposes in mind.

This paper presents a procedure for calculation of electrical submergible pumping installations in oil-producing wells. The calculations take into account the existence of vertical multiphase flow in the production string. Special attention is given to the determination of the proper pump setting depth, and to the pressure head which must supply to the well fluids. The consideration is made that the amount of entrained free gas, which goes through the pump, must be such that it does not noticeably alter the pump performance curves. The procedure was programmed for an electronic computer.

To protect the investment in a submersible pump all facilities available must be used to insure against premature unit failure. A combination of common oilfield test procedures, including the recording of fluid volumes, pressures, unit voltages, and amperages can provide the desired insurance. A correctly designed submersible pump will provide a relatively maintenance-free, long duration operation. The usual cause of premature failure of a properly designed unit is an unattended correctable mechanical malfunction which results in downhole failure.

Submersible pumping applications are becoming more and more commonplace in the oilfields. Many oilfield personnel are quite familiar with the beam pump and its characteristics. Just as this unit has served reliably over the years, a properly installed and controlled submersible should give a respectable service life and should pay for its existence many times over. Maximizing the service life of submersible equipment entails the proper utilization and understanding of submersible motor controls.

The design and construction for subsurface disposal of industrial waste water is presented in this paper, based on the results of El Paso Products Company Mize No. 1 Disposal Well, Ector County, Texas. The data presented encompasses the drilling, completing, and operating of a disposal system for the Odessa Petro-chemical Complex.

The subsurface electrical pump, being a relatively high-volume type of artificial lift, is most applicable in wells which are under the influence of a strong water-drive or waterflood and have high water cuts or low GOR"s. The economics of producing these high water-cut wells is directly related to the cost of electrical energy used and the operating lift of the equipment. To optimize the electrical cost and operating life, one must understand the basic characteristics of the motor, centrifugal pump and cable.

Tiltmeter technology, as a source of data acquisition for fracture mapping, has been largely neglected. The benefits of this technology, however, warrant a closer look at its capabilities. This paper serves to re-introduce tiltmeters, illustrate how they work, explain their value, and explore how tiltmeter technology is pushing forward.

Hydraulic pumping made its appearance as a method of oilwell artificial lift in the early 1930"s. Since that time this method has found wide acceptance, especially in deep, high volume pumping. Because the unit is located near the bottom of the well, understanding the operation and condition of the downhole unit can often be a problem for the producer. This paper presents a well-site analytical method using pressure and production data to determine useful information about the overall condition of the hydraulic pumping system along with the well's potential.

One of the most expensive pieces of production equipment to be placed downhole is a sucker rod pump. The performance of this pump can greatly affect the ability of a well to produce. By collecting information about a pump and its components through failures and successes, the operator can operating costs, decrease downtime, and increase production. Computers placed at the pump repair shop can capture detailed information about the configuration of a pump when it is assembled or when it is repaired, before being placed downhole.

A review of the "building blocks" of subsurface pumps illustrating blunders of the past and headaches of the future in the selection of pumps. Included will be methods on how to properly select sub-surface pumps.