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Blocking gels have been used in low temperature zones for many years. Blocking gels are employed in workover operations to isolate producing zones. The problems with isolating high temperature zones were mostly due to the insufficient or unstable rheological properties of the crosslinked blocking gels. Recent developments of unique crosslinkers, stabilizers, derivative polymers and enzymes have provided significant contributions to the oil and gas industry.

CO2 foam properties were measured to 300_F in a high temperature, high pressure pipe viscometer. The effects of foamer type and concentration on high temperature CO2 foam rheology were determined. It was found that, above a certain level, further increases in foamer concentration provide little corresponding increase in foam stability or rheology. CO2 foam stability can be improved by the use of higher concentrations of gelling agent. Test data indicates that higher concentrations of foamer and gellant are required to produce stable CO2 foams, as compared to N2 foams.

Fracture acidizing systems previously available are acid and temperature sensitive. This paper will discuss a new crosslinked acid system that is compatible with up to 28% HCl and that has been successfully pumped at bottom hole temperatures to 250_F. Fluid rheology, friction pressure, fluid loss, additive compatibilities and acid reaction rates supporting the use of this system at 50 and 60 lbs./gal. polymer loadings are presented.

This paper will discuss prior publications of the lift capacity for sucker rod lift method versus net effective lift depth. Additionally, the current day upgrades in lift systems and availability of larger downhole pumps will be investigated to provide current high rate lift capacity versus depth.

While operators are always searching for new techniques to produce oil more efficiently, the economic climate in which the oil industry finds itself today has renewed efforts to seek out new opportunities to improve operational strategies. This paper will discuss a field scenario in which gas locking problems were impacting production in a mature field in West Texas operated by Texaco. This field was being produced with CO2 injection and was experiencing increases in beam lift failures and high CO2 production.

WellChek Database has been developed to provide a well specific, tubing string profile from an on-site used tubing inspection unit. Tubing is classified as it is pulled from the well, providing sequential information on a per joint basis within the string. Before being returned to production a detailed report of the tubing string is provided online, which can be viewed together with previous inspection results, containing critical information to the well management program. Routine well maintenance provides the opportunity for inspection data to be easily obtained.

Underlying part of a several county area in western Texas is the Horseshoe atoll, which will measure about 90 miles across in an east-west direction and about 70 miles from north to south. Producing from the Canyon Reef limestone at approximately 6,700 ft., which is a part of the Horseshoe atoll that underlies Scurry County, is the Sharon Ridge Canyon Unit. The Sharon Ridge Canyon Unit is a pressure maintenance project using fresh surface water injected on a peripheral pattern. The water distribution system is made up of both bare steel and cement lined pipe.

The Conventional beam pumping unit, a Class I lever system, was used almost exclusively in artificial lift applications from the 1700's until the late 1920"s. At that time, a "reversed" Conventional geometry design (Class III lever system), called an Air Balance unit because of its pneumatic counterbalance system, made its appearance. Later, in the mid 19503, a second, Class III lever system, or "reversed" geometry unit, was introduced and named the Mark II.

Inefficiencies in sucker rod pumping systems due to gas interference are major concerns for petroleum producing companies throughout the world. This paper describes an innovative cage design that is based on years of exposure to sucker rod pump inspection and repair from many varied field conditions and on compression and flow comparison testing. Observance of results obtained from working closely with the Alberta Research Council in Edmonton Alberta on numerous projects specifically related to conventional, thermal, vertical and horizontal sucker rod pumping was also influential.

The purpose of this paper is to discuss HNG Oil Company's drilling, completion, and producing operations in the Sawyer (Canyon) Field, Sutton County, Texas. The field is located south of Sonora, Texas as shown in Fig. 1. HNG has 134 productive wells, 60 percent of the field, on 58,000 acres with 220 offset proven locations yet to be drilled. The Canyon in this area is characterized by limited extent low permeability lenticular sands. The average well stabilizes at approximately 300 MCFPD and has an initial bottomhole pressure of about 1900 psi.

HNG Oil Company has completed over 20 deep gas wells in the past four years with remarkably few problems. The majority of the wells are located in the Delaware Basin of West Texas and range in deliverability from less than 1 MMCF/D to over 30 MMCF/D. Although each completion is different, the same basic steps were followed. Each was perforated in acid with a limited number of deep penetrating, burr-free perforations, and was originally stimulated with a moderate volume of 15% HCl using ball sealers to divert the acid.

This paper is intended to have a twofold purpose. While the data cited refer to the specific problem of borehole instability as affected by the drilling fluid, it is also intended that the approach taken toward alleviation of the borehole instability problem through mud technology in this case is applicable to other drilling problems as well. Borehole instability serves as an example of a drilling problem to illustrate how drilling problems may be approached in an organized manner by way of the drilling mud.

Fissile shale has strong potential to cause severe wellbore instabilities. It is highly laminated and can split easily into thin layers along its bedding planes. With the high concentrations of clay minerals, this type of rocks usually has high cation exchange capacity. Dispersion may not be strong, even in water, but the rock becomes highly broken mainly along bedding planes once it is in contact with fluids. Finding suitable drilling fluids to stabilize reactive fissile shale formations is an area of active research in M-I SWACO.

The Horizontal Well Artificial Lift Consortium is now an official, funded project. The purpose is to develop an improved understanding of the issues for production horizontal oil and gas wells, especially where application of artificial lift is required.
The research is primarily conducted at the Univ. of Tulsa. There are currently 10 member companies with the number expected to grow.
This presentation will give an update of the status of the Consortium and the current research focus.

The oilfield adage that "you cannot hurt a good gas well or help a bad gas well" is not necessarily true. The new Horizontal-Spinner coupled with vast interpretation experience of temperature logs has revealed a number of completion problems that can be overcome. The gas source is not always where the perforations are placed and many perforations are not opened when treated. In deep gas wells the present formation logging tools do not properly identify the productive zones; and the present perforating and treating techniques do not create access to all the zones to be tested.

Field tests were performed to better understand the effectiveness of hot oiling to remove paraffin in downhole tubulars. In particular, the tests were designed to investigate the depth to which paraffin might be melted. The temperature decay following the end of the treatment, pump capacities, and heat loss assumptions were used to estimate the treated depths. The results indicated that annular hot oil treatments might be effective for paraffin wax that is very near the surface but the effective treating depth is very limited.

The desirability of using a tubing anchor in a pumping well to increase effective pump stroke and to reduce wear on sucker rods, tubing and casing has been recognized for many years. It is well known that an unanchored tubing string "breathes" as a portion of the fluid load in the tubing is alternately transferred between the tubing and the sucker rods during the pumping cycle. The elimination of this movement of the tubing string by means of an effective anchor should provide obvious benefits to the operators of rod pumped wells.

The success ratio of squeeze cementing operations in the past has been poor. A lack of knowledge of downhole conditions and formation characteristics was partly to blame. Proper cementing materials for downhole conditions were not always available. Recent development of cementing materials and techniques has greatly improved the success ratio of squeeze cementing. New tools are available to provide a greater knowledge of downhole conditions to determine the existing problems in the well.

An Operator/Pumper is typically expected to produce their assigned wells in a manner that results in a maximum allowable production rate at a minimum of cost. However, they must do so with the wellbore conditions, equipment, and operating environment they as assigned. This paper will present some tools and methods that the Operator/Pumper can utilize to help optimize a rod pump well.

The purpose of this paper is to discuss and emphasize the importance of the royalty owner to the oil industry and the direct effect which unfavorable owner relations has on your company's profit. This paper will be divided into six principle parts: (1) Introduction; (2) The importance of the royalty owner; (3) The landman's role in royalty owner relations; (4) The royalty owner's role as the company's constituent; (5) Ways of preventing adverse relations with royalty owners; (6) Summary.

This paper gives quantitative calculations of the effects of Carbon Dioxide and pressure on the solubilities of formation minerals in a West Texas brine. Increased pressure makes anhydrite and gypsum significantly more soluble. The solubilities of carbonate minerals are increased to a lesser extent. The presence of Carbon Dioxide causes large increases in the solubilities of carbonate minerals, thus exacerbating the scale problem. Carbon Dioxide will greatly reduce the pH of injected or connate water, but this undesirable effect is reduced by the buffering action of carbonate minerals.

Gas and liquid are frequently transported simultaneously in the same pipe. Common occurrences include pipelines for gas and oilfields, piping in refineries and process plants, and steam injection and geothermal production systems. When two-phase flow (i.e. gas-oil-water) occurs in a pipeline, the phases separate geometrically in the pipe into various flow patterns. In general, the flow pattern that results depends upon several flow parameters, of which phase velocities and pipe inclination are the most important.

When designing a Production Facility, many engineers and production foremen are confronted with a multitude of codes, standards, best practices and even OSHA requirements. Often, the facility design is based on old outdated codes, standards, or practices. Lack of proper engineering design can lead to equipment failure, lost production, human injury or harm to the environment.
The safety of a facility is a direct function of how the facility is designed. The oil and gas industry has produced many codes and standards, which were developed primarily in response to incidents that had occurred.

The author developed a computerized technique for sucker rod system design that attains the pumping mode with the lifting efficiency being at a maximum. This optimum pumping mode gives the most economical combination of plunger size, stroke length and pumping speed. The proposed design procedure applies to conventional pumping units and assures minimum energy usage for the production of the required liquid rate to the surface. The method presented in this paper involves designing of the rod string for each pumping mode used in the process of selecting the optimum mode.

Throughout the world the most common method used to artificially produce wells is through the means of sucker rod lift. Low producing efficiencies caused by incomplete pump fillage is the most common operational problem experienced by these the sucker rod lifted wells. Incomplete pump fillage is the result of having a pump capacity that exceeds the production rate of the well or having poor gas separation at the pump intake and a portion of the pump capacity being lost to gas interference.