Research And Design Of Casing Pressure Control System For Stable Oil Well Production

High GOR wells contains a lot of free gas, the gas distribution in the oil casing annulus within, In the oil process, the gas dissolved in the crude oil into the pump and with the discontent caused by the charge pump, reduced pump efficiency, yield. traditional methods for control gas casing was installed in Inoue relief valve and other devices, but the traditional control devices require judgment based on experience artificial casing pressure, with operating arbitrary degree of automation and low defects. Secondly, in the downhole pump suction anchors were installed at the entrance of gas and gas separation, but limited oil and gas separation. for the shortcomings of traditional control devices and considering the charge pump gas caused dissatisfaction impact factor, the research and production of the well pressure stable relationship, according to well pressure gradient, improved mathematical model to determine the reasonable casing pressure, through the design of the control system is stable and well casing pressure in the pressure within a reasonable range, to improve pump efficiency and stable oil production purposes.The main results of this paper are as follows:1.Researched reasonable casing head gas pressure and stable relations theory, establish a reasonable set of pressure calculation model.According to the regulator sets oil production and control method field, detailed analysis of the internal mechanism of the process of internal control wellbore casing pressure during pressure changes, study the formation and casing head gas affected factor. with respect to the method of conversion of existing gas anchor, anti-pump leakage, ground parameter adjustment method to achieve stable, the proposed change by controlling the set pressure of the fluid level and sinking to achieve improvements pump full coefficient, stable production program. establish a reasonable set of dynamic equations model to calculate pressure, based on historical oil production data and combine multiple linear regression theory analysis, oil production and casing pressure, gas-liquid ratio, as a function of pump efficiency, etc. the formula to get a reasonable set of pressure and output, and as a judge casing gas pressure is a reasonable basis and guidelines. the advantage is that both computational model uses oil pressure while staging a physical model combined with historical production data analysis, making the results more accurate and reasonable, the effect is significant.2. Designed and completed a stable oil production casing gas pressure control system.Traditional casing gas control apparatus and method, design a stable oil production casing gas pressure control system. compared with the traditional constant pressure valves and other control devices, the advantages of the system is that a reasonable set of pressure is calculated by the software, without having to manually adjust the valve, more automated, the system calculates the pressure by the host computer software systems, pressure sensors and processing circuits acquisition actual casing pressure, PC software system calculates reasonably well casing pressure, casing pressure control circuit to obtain a reasonable value through the signal transmission circuit, the control strategy based on the output control signal to drive the valve action, ensure stable oil actual pressure value within a reasonable range of computing casing pressure to stabilize oil production, the system pressure control process to avoid deflation uneven impact on the formation energy3. Researched and realization pressure computing software system.Used C#and MATLAB programming methods to achieve joint pressure calculation software system, system includes a pressure calculation module, the system main interface, data interface, data transfer interface function modules, MATLAB prepared pressure calculation model program, compile and generate dynamic link library file, call the file to calculate the direct pressure calculation module runtime, special software system, to provide manual data input interface, field engineers and input through the interface reasonable judgment based on experience casing gas pressure to control casing pressure. verify the accuracy of pressure calculation software system, the results show:a reasonable calculation software sets the pressure value is more accurate, the actual production to meet demand, yield and actual yield is calculated relative error of less than5%.4. System testing to verify that it meets design specifications and requirements.After the system design is completed, the system software and hardware combined test, verify the system is working properly. deflate the control system testing and regulator testing, the actual test showed:control fast and accurate, stable and strong pressure capability, the system meets the design specifications and requirements, by comparison with the traditional mechanical bushing or spring air control device, the system overcomes the shortcomings of manual and automated, high intelligence, to achieve the purpose of improving the efficiency of the pump stable oil production.