Acid Polymer gels having pH less than one have been crosslinked for retarding the chemical and physical activity of hydrochloric acid on calcareous formations. Hydrochloric acid concentrations from & percent to 28 percent have been successfully crosslinked. This new and unique stimulation fluid offers high viscosity with adequate shear stability, perfect support for proppants and clay stabilization. Additionally, the fluid provides effective fluid loss control and retardation of acid reaction enabling live acid to penetrate deeper into the formation for better formation conductivity and practically a residue free break for rapid clean-up of the well after the job. Results of lab and field tests show this new Acid Crosslinked System to be effective stimulation fluid for acidizing and acid fracturing in calcareous and sandstone formations having low formation permeability.

Lifting problems in producing wells can drastically cut the oil operator's profit on initial investment. Well conditions that cause severe lifting problems are: 1. High sand content in the producing fluid which will often damage or freeze the bottom hole pump. 2. Paraffin or gyp accumulation on the tubing I.D. and sucker rods, resulting in eventual plugging. 3. The oil produced is of low gravity and cannot be efficiently pumped in cold weather. Wells with the above conditions are presently being pumped with optimum efficiency through use of a new method of artificial lift. The method applies the principle of sonic energy to oil well production. The equipment used will vibrate the tubing string in such a manner that valves in the tubing collars will lift the fluid to the surface.

Corrosion surveying of pipelines can now be performed by an instrumented pig which travels through the line with the fluid normally transmitted. A continuous log of the entire line shows the areas where corrosion pitting has occurred.

This paper will discuss the properties and applications of a new water-base fracturing fluid. In particular, it will discuss its leak-off characteristics, its rheological behavior, and its proppant-transport capability. Additionally, it will give examples of its use in the field, including production information. Beginning in the late 1960"s, intensive research was done in the area of improved stimulation fluids. This led to the development of a variety of crosslinked fracturing fluids based on both organic and synthetic polymers. These fluids featured extreme viscosities, perfect or near perfect proppant transport, and good pumpability without excessive friction drop. In nearly all cases, high polymer loadings were required for optimum performance. In the case of the natural polymers, the higher loadings resulted in excessive residue and consequent sand-pack damage. The synthetic polymers left no damaging residue; however, they were prohibitively expensive. The subject gel was designed to overcome the limitations of the early crosslinked gels. It features a moderate polymer loading which, when complexed with an organometallic chelate, furnishes high but not excessive viscosity combined with perfect proppant transport. It features good leak-off control and is residue-free when broken. The base polymer of this system is carboxymethylcellulose which is hydrated prior to pumping. The complexing agent is added continuously after sand is dispersed in the base gel. Since the concentration of organometallic chelate is low, an air-drive proportioner ha's been designed and built with suitable control and monitoring features. This device is also described in the paper.

The use of a fluid containing an abrasive for perforating casing and cleaning open hole has been an established technique for many years. Generally, the jetting tool is installed on tubing along with a collar locator, tubing hold-down, centralizer, and in some instances an anchor swivel. The tool is then lowered to the desired perforating or jetting depth to be cleaned. Perforating or jetting operations are initiated by pumping the abrasive fluid into the tubing conductor, then to the jet body, and out the jet nozzles at relatively high differential pressure on to the surface or surfaces to be cut or penetrated. Conversion of the pressure into kinetic energy imparts high velocity to the abrasive particles, which upon impact with the formation face or casing wall will erode the material in an organized pattern. A prime deterrent to effective hydraulic perforating an openhole section in an old well is the extended stand-off distance at which the perforating or jetting operation must be performed. This condition is particularly aggravated and critical in "shot" holes and openhole sections which have been previously acidized or fractured and have since become scaled or plugged. The purpose of this paper is to present a self-decentralizing hydraulic perforating tool which produces unbalanced forces and which, when coupled with a flexible fluid conductor, will provide a novel combination resulting in near zero stand-off hydraulic perforating conditions for improved effectiveness in perforating or penetrating a formation face in open hole. A sketch and general operating procedure plus some equations involved in development and several pertinent to its effectiveness for penetrating rock or scale are set forth. In general, this discussion is presented along operational lines and is substantiated by test target results, pictures, and after treatment responses. These results present concrete evidence, confirmed by representatives of various oil companies in West Texas and Southeast New Mexico that the successful development of the tool for perforating or penetrating formations in open hole or "shot" hole is an accomplished fact, and that this process can be relied on to penetrate rock or scale.

"Conventional acidizing has ignored relative permeability effects by attempting to inject aqueous fluids into zones filled with crude." Since most oil wells in the Permian Basin today are on water flood or produce large quantities of water, relative permeability is an issue. Therefore in zones where the water saturation is high due to depletion of the higher permeability zones and/or natural fractures, acid tends to enter these zones instead of the oil zones where the acid is needed and wanted. This in turn leads to higher water cuts instead of increased oil cuts. A new non-particulate, non-gaseous material has been developed to effectively divert acid away from highly water saturated zones. This new material's diversion capabilities are dictated by the relative permeability of the formation as with foam, but it offers a simplicity and accuracy to the treatment that foam and other diverting agent can not. This paper discusses a case history that utilized this material for acid diversion in a water flood.

A new technology now exists to expand solid stainless steel tubulars for downhole remedial pre frac applications. Very different from other expandable technologies, mainly due to the setting process and the capacity of the tools to expand until they're in contact with the casing, this technology has now been used successfully in several countries as a precision intervention to resolve a variety of downhole problems. This paper will: provide an introduction to inflatable packer expandable steel technology, what it is and how it works; discuss some of the issues identified and resolved during the development of the technology; provide case histories using examples of pre frac jobs DV tools and sliding sleeve repair jobs from operations in US, and Western Canada; summarize the features, benefits, and limitations of the technology; present the solutions available today in the US.

Delivery of recovered hydrocarbons from oil fields to refinery, storage and consumption points is related to significant oil products loss. Losses occure all the way from oil production up to receiving them by consumers. The losses are due to outfow, evaporation, weather factors, equipment imperfections, etc. However, according to the case studies, approximately 75% of liquid oil products losses are due to evaporations. Hydrocarbons evaporation is concerned with not only material losses, but also causes environment polluction by toxic hydrocarbons. Therfore, duel losses reduction is an important economic and an environmental problem. Recently, a new tchnology was developed to prevent VOC emissions from tank batteries. The pontoon structures made of oil-resistant rubber-textile or synthetic material are used to prevent VOC emissions. Maintenance and dump of pressure in a pontoon space is carried out by means of the compressor and gas collector. The device was tested in FSU oil fields.

The sucker rod connection poses several problems to rig crews as well as the oil companies. The first issue the crews have to deal with is the face that there are two elements to a rod connection: The lower and the upper rod interfaces. Making up both elements to precise circumferential displacements at the same time is almost impossible.
This paper will deal with these issues and will illustrate a new tool that solves the makeup problems and at the same time, gives the crews a method to remove or replace a coupling. The tool can be instructed to make up either both or only one element of the connection to the precise desired CD. The two CD's are measured independently.

A new treating method has been designed for use in wells in which injectivity has been decreased by deposition of polymer residue incurred in polyacrylamide polymer and copolymer treatments. This treatment consists of one or two stages: an oxidizer stage followed by an acid stage, or a combined acid-oxidizer stage. This treatment is effective against polyacrylamide polymer and copolymer deposits near the wellbore that will not respond to conventional treatments. It is known that polymer injection can gradually lead to a decrease in injectivity. solid polymer, This injectivity decrease can be due to incompletely dissolved improperly inverted emulsion polymer, and/or deposition and adsorption on the rock face. These blockages can contain inorganic as well an organic components. An acidizing treatment is necessary for the inorganics while an oxidizer treatment is necessary to treat the organic constituent. The new treatment method consists of a strong oxidizer that is acid compatible. The pH of the oxidizer stage can be adjusted to suit the need of a given well. The pH adjustment can also control the release rate of the oxidizer. These solutions are mildly corrosive to steel. The oxidizer and acid can be split into two stages if the mixture proves to be too corrosive, or if a stronger acid is desired. These treatments have been effective without the acid stage in polymer injection wells. Laboratory data and preliminary well treatment results are presented to show the effectiveness of the oxidizer alone and with acid.

The productivity of oil and gas wells can he improved through the use of efficiently designed acid fracturing treatments. The approach to acid fracturing treatment design presented in this paper enables a comparison of the production increases for various types of acid systems. In this study, four hydrochloric acid systems (plain, foamed, gelled anti crosslinked) were used to design acid fracturing treatments. An acid fracturing stimulation design comparison for three reservoirs is presented.

A new promising enhanced oil recovery technology has developed. The technology involves in-situ generation of carbon dioxide to recover trapped residual oil from reservoirs. This technology has two at least unique features that set it apart from existing technologies. First, CO2 is injected as part of a dense liquid phase (not simply compressed CO2). Because the injected fluid is a dense liquid at ambient conditions, there is no need for the expensive compression costs that are associated with convention CO2 injection processes. The gravity head associated with the fluid column allows CO2 to be injected in a more cost-effective manner. This proprietary technology allows CO2 to be released in-situ after injection into the reservoir. A second unique feature of this new technology is that a proprietary surfactant formulation forms foam when the CO2 is generated in situ. The slim tube and core experimental results demonstrated advantages of the new technology. The technology also was tested in Russian and Chinese oil fields.

The formation of troublesome organic deposits during oil and gas production is a significant cause of decreased production and increased lifting costs. Traditional methods of mechanical and solvent-based removal are time consuming, expensive, and can create additional problems of re-deposition and dehydration facilities upsets. A novel process has been developed to remove organic deposits from hydrocarbon producing wells and equipment by generating an exothermic reaction that melts and disperses paraffin wax and asphaltenic
deposits. The reaction product is a powerful paraffin dispersant that prevents redeposition after the temperature returns to normal. The process is non-aqueous, which does not cause troublesome emulsions or potentially dangerous gas production.

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.