Design And Control Performance Research Of Closed And Cut-off Device For Pressure Operation

With the rapid development of my country's economy,people's demand for oil and natural gas is increasing,which puts forward higher requirements on the efficiency of on-site energy extraction in oil and gas fields.Due to the frequent operation of oil extraction equipment downhole coiled tubing joints,there are problems such as aging and corrosion,as well as tubing jams during workover operations,which greatly affects the efficiency of workover operations.This article analyzes the advantages and disadvantages of existing tubing internal cutting equipment at home and abroad,and combines the basic operation process of domestic workover equipment to develop a closed cutting device that can effectively integrate with the existing pressure working machine.With reference to the operation mode of the manual tubing external cutting tool,research is carried out from the structural composition,working principle and main technical parameters of the airtight cutting device,combined with the actual working conditions of the workover operation to determine the structural composition and design requirements of the device.On this basis,the cutting mechanism is further studied,and the influence of the rotation speed of the rotary assembly and the feed of the cutter assembly on the cutting effect of the tubing is analyzed through the tubing cutting experiment,so as to determine the best motion parameters of the cutting tubing.According to the maximum cutting resistance and feed accuracy requirements of the cutter during the tubing cutting process,the calculation and selection of the ball screw of the closed cutting device transmission mechanism are carried out,and the maximum torque required to drive the rotary assembly and the ball screw to rotate is calculated.Combined with ANSYS finite element simulation software to conduct transient dynamic analysis of the transmission gear to ensure that it meets the mechanical performance requirements during the transmission process;and conduct pressure performance analysis of the rotary component to ensure that the main structure strength is consistent with the pressure operation under the impact of 30MPa well pressure on-site safety and tightness requirements.After completing the structural design of the entire device,the closed cutting device is further designed for hydraulic control loops to meet the requirements of rotation and feed operations when cutting the oil pipe under pressure.Combined with the principle of valve-controlled motor,a mathematical model of the cutter feed system is established,and the hydraulic components are calculated and selected.On this basis,an adaptive fuzzy PID control strategy based on particle swarm optimization is proposed to improve the control performance of the valve-controlled motor cutter feed system.The results show that the overall rotation angle tracking performance and tracking error of the system under this strategy can meet the tubing cutting accuracy requirements,and its dynamic adjustment performance is also better.Figure[55]table[8]reference[69]...