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An 87-well lease in a major West Texas oil field has been converted to automatic operations except for custody transfer. The system automatically controls the production from the wells and the periodic well testing scheduled for the lease. All wells on the lease are pumped with standard, electrically powered, beam units. Periodic well testing, formerly done manually, is now performed automatically by means of electrically operated time controllers which divert on a pre-determined schedule production from the well to be tested through well test units.

Pressure coring offers a method for obtaining In Situ reservoir Saturations. However due to the requirement of pressure balance during coring it has henceforth been limited to use in reservoirs with pressure gradients greater than 0.25 psi per foot. This paper will describe techniques used to obtain the first known successful pressure cores taken using a foam mud system; thereby extending the useful range of pressure coring to under-pressured reservoirs. Stable foam is a compressable Non-Newtonian fluid that requires special design considerations when used in conjunction with pressure coring.

The crude oil produced by ConocoPhillips in its South Guymon Unit is very paraffinic and has caused paraffin problems in formation, pumps, tubing, casing, flowlines and separators for years. Costs of production had been increasing because of lost production, plugged pumps, workover problems and stripping jobs. Many different types of treatments including cutting, solvent/chemical treatments, hot oil and hot water/chemical had been tried but all had been unable to reduce the problems or reduce costs.

Many oil-producing areas suffer from troublesome paraffin deposition in production and transportation operations. The use of paraffin inhibitors, which are sometimes referred to as wax crystal modifiers or pour point depressants, have been effective at reducing plugging caused by paraffin deposition. To be effective these materials must be applied at a point before the paraffin falls out of solution and they must be present on a continuous basis.

In Coalbed Methane (CBM) production wells using Electric Submersible Pumps (ESP), it is common to control fluid levels to the required setting by the use of Variable Speed Drives. However this can cause high harmonics and, as a result, in the Powder River Basin in Wyoming, power companies have become increasingly reluctant to allow the use of variable speed drives and an alternative method of well control had to be found. A totally new approach to controlling ESPs, and thus the well fluid levels, was conceived.

Diversified efforts are continually being made to reduce artificial lift operating costs and/or increase oil production. The intent of these efforts is to put more profit in producing operations and prolong the economic life of present oil properties. Also, a greater ultimate recovery means more efficient use of our natural resources.

Lack of submergence and gas interference are the principal causes of poor pump efficiency; both create fluid pound. Fluid pound contributes greatly to rod parts, bearing and gear failure in pumping units, V-belt failure and prime mover damage. The greatest loss is in production when gas interference is present. Subsurface gas separators of many designs are being used; these separators are essential. The more gas that is separated from the oil and permitted to escape up the casing before it can reach the pump intake, the better.

With over 600,000 rod-pumped wells in North America alone, failure of this common artificial lift system substantially raises lifting costs. Among the leading causes of failure in sucker rod-pumped wells are rod parts and tubing wear. Typically, an operator has little reliable data with regard to tubing deviation and the root cause of rod-on-tubing wear and tubing or sucker rod failure. In many cases, a minority of wells constitute the majority of repeat failures and workover cost in a field.

Optimum production of gas wells requires static and flowing pressure surveys to detect excessive liquid loading. Wireline pressure surveys have been customary in spite of their cost and potential safety risks. Developments in digital acoustic fluid level technology have resulted in being able to undertake not only static bottom hole pressure calculations from fluid level measurements but to extend this technology to flowing pressure gradient surveys in gas wells. The new procedure involves monitoring fluid level and pressure in the tubing during a short term test sequence.

A process is being developed to provide steel downhole tools and components with a proprietary Al2O3 based metalloid coating that appears to provide a barrier to hydrogen embrittlement and other corrosion forms. Laboratory tests of hardened steel specimens, stressed to 96% of the yield strength and complying with NACE TM-01-77 test requirements, resulted in "no 720 hour failures" or "indefinite time to failure" due to hydrogen embrittlement or sulfide stress cracking. Comparable specimens failed in less than five hours.

Abrasion and corrosion create costly problems in oil pumping wells. The cyclic action of the sucker rod string causes the rods, couplings and tubing to wear away. At the same time, they are being corroded away by the chemicals in the produced fluid. Eventually, the rods, couplings and tubing will fail and must be replaced. The resultant down-time to repair or replace the system is a great expense for the well operator.

The abrasive jetting technique consists of jetting high velocity streams of sand laden fluid from specially designed subsurface jet guns. These jet streams have the ability to perforate through casing and cement sheaths in a few minutes, and penetrate deeply into the formation behind.

A fully automated rod tong has been developed and deployed, which significantly improves well profitability by increasing mean time between failures of sucker rod connections. There is no other system available in the industry today that can automatically make sucker rod connections up to the manufactures" specifications. The rod connection service provides reliable, long term connection performance by controlling the CD to within manufacturers" specifications for every rod connection.

The Citronelle oil field, underlying the town of Citronelle, Alabama, is located on a topographic high approximately 350 feet above sea level (Figure 1). The existence of this surface anomaly encouraged oil and gas exploration in the Citronelle area. Oil was discovered in 1955 with the drilling of the Donovan Well #l on a vacant car lot. The discovery well flowed about 500 barrels of oil per day with an initial bottom hole pressure of 5000 psi. As discovery of the field continued, over 450 wells were drilled on 40-acre tracts covering about 17,600 acres.

Since the popularization of oil well acidizing during the 1930's the specific problem of acid corrosion of tubular goods has been a fertile yet frustrating field for the corrosion chemist. Included in this paper will be a brief discussion of corrosion theory which will serve as a prelude to a discussion of more recent research developments which point to new parameters critical to the understanding and development of environmentally-acceptable organic acid corrosion inhibitors for the deeper and hotter wells of the 70"s.

Stimulation of carbonates with acid has been and will continue to be one of the most economical means of improving the performance of both production wells and injection wells. Performance improvement is accomplished through the proper match-up of fluids and techniques to the reservoir The beginning of a successful stimulation starts with an understanding of the reservoir composition and pore system.

One of the most effective methods of carbonate stimulation is acid fracturing. Development of fracture geometry sufficient to allow etched penetration to provide economic production increases is dependent upon several factors, one of which is pump rate. High rates and/or lower hydraulic horsepower requirements can be critical to success to one of these projects. Many times wells lack the integrity or flexibility to be treated down casing. Treating down tubing affords highly viscous fluid's opportunity for rate restrictions due friction pressure.

Mud solids can cause severe productivity impairment which can only be prevented by the use of acid-soluble muds. Conditions justifying the use of such muds are as follows: 1) Highly permeable formations (say above 500 md). 2) Carbonate reservoirs of low matrix permeability whose productivity depends on a fracture network. 3) In production repair wells where the risk of lost circulation into depleted reservoirs and of plugging established flow channels is high. 4) When it is advantageous to have an acid-soluble filter cake, e.g.

This paper explains a new approach in choosing the most acceptable treating fluid and a history of field applications using the new method.

Acoustic instruments have been used routinely for many years as an aid in analyzing well performance of normal-pressure oil producers. Recent developments in equipment and techniques now permit more-accurate calculations of acoustic static bottomhole pressures at surface pressures up to 15,000 psi in corrosive (COP and H2S) environments. Equations and charts are presented herein for determining static bottomhole pressures from acoustic and well data. Also, a special technique is recommended for shutting-in a well which in most cases will yield more-accurate results.

The ACE log is an efficient aid in determining the quality of reservoir isolation achieved through primary or squeeze cementing. A subject of controversy since its inception, cement bond evaluation has improved with advanced technology and with continued concern by the industry for an effective evaluation meth0d.l A better understanding of the operations principles by service company and operations personnel, meaningful calibration, and the application of logic to interpretation are some of the factors responsible for increased acceptance by the industry.

Electronic equipment is available to determine the fluid depth in oil wells quickly and accurately. The fluid depth is determined by producing a sound wave at the surface and recording the reflections on a strip chart. Therefore, the instrument is called an acoustical well sounder (AWS). The most common means of producing the sound waves is by firing a black powder blank into the annulus. Recent innovations of gas guns have improved the safety and performance, and decreased the cost of using as AWS.

The Coalbed Natural Gas Industry, or Coalbed Methane (CBM) continues to gain global popularity and momentum. However today, CBM operations are one of economic challenges. Varying coal seam depths, rapidly declining water production rates, uncharacteristic well completions, sand, coal fines, etc., prohibit using just one form artificial lift equipment. Successful CBM production operations demand multiple product lines. Weatherford determined that a new approach was needed that offered multiple product lines in addition to modifications of conventional artificial lift products.

The Adjustable Valve Rod and Pull Tube Guide is designed to allow for precise spacing in a down-hole sucker rod pump. In historical installations the spacing is based on the valve rod or pull tube length. This length is usually in one inch increments from the factory, or the rod or tube is field cut and threaded to maximize the pump compression ratio. This patented guide allows the spacing to be adjusted with greater precision and will compensate for manufacturing tolerances and reduce field cutting and threading of pull rods and pull tubes.

Virtually every oil production company and many gas producers, both major and independent, must use one or more forms of artificial lift to assist in producing their wells. Yet, most companies do not have artificial lift experts. In fact, many companies don"t even have engineers trained in artificial lift. And almost no companies have artificial lift research and development programs. In fact, most companies must depend solely on the service companies to provide the artificial lift technology, products, and services they require.