Research On The Non-stop Plugging Device For Oil And Gas Pipeline

Due to factors such as perennial corrosion and external aggression of oil and gas pipelines,especially for pipelines with a long service life,problems such as damage and leakage are increasingly significant,and the relevant departments have invested more and more energy in the maintenance and repair of oil and gas pipelines.In the process of pipeline maintenance,it is necessary to isolate the faulty pipe section,otherwise it is likely lead to safety accidents.So it is of great significance to develop a plugging device that can quickly seal at a specific pipe section.At present,the more commonly used pipeline plugging technologies include non-stop pressure-opening plugging technology and high-pressure intelligent plugging technology in the pipeline.The process of plugging with pressure outside the oil and gas pipeline is cumbersome.The technology can damage the pipeline and has potential hazards.The high-pressure plugging technology inside the pipe cannot transport oil and gas during the plugging process which make the pipeline lose its ability to transport oil and gas.A new type of oil and gas pipeline non-stop transportation plugging technology was proposed for the above problems.The new technology adopted an in-pipe plugging device to isolate the faulty pipeline section.During the faulty pipeline is under repair,the pipeline can also transport the oil or gas.This paper mainly completes the following aspects:(1)Consult relevant engineering data and construction requirements at the pipeline repair site.On the premise of making full use of existing pipeline maintenance equipment,plan the non-stop plugging process of oil and gas pipelines and design the overall structure of the plugging device.(2)According to the proposed non-stop plugging process,an oil and gas pipeline with a diameter of Φ324mm and a pressure of 3MPa was taken as the research object for overall design and feasibility analysis.A specific structural design of the pipeline non-stop plugging device has been designed.The Solid Works three-dimensional model of the pipeline intelligent plug was established,and the structural dimensions and safety strength of the key components were designed and checked.(3)According to the mechanical structure and other requirements of the plugging device,the hardware of the communication and control system of the plugging device was designed.The master chip selection and circuit design were completed.And the upper computer and the lower computer software of the plugging device control system were developed.Design a stepping motor position control algorithm based on the S-type acceleration and deceleration algorithm.The upper computer can send control instructions and receive and dynamically display the data sent by the lower computer.The lower computer can control the stepper motor and solenoid valve.(4)According to the working requirements of the plugging device,the finite element analysis software ANSYS was used to analyze the contact between the slip and the inner wall of the pipeline.The results of static simulation showed that the anchoring process did not cause permanent damage to the pipe wall.The finite element analysis software ABAQUS was used to study the sealing performance of the sealing unit.And the reliability of the designed rubber cylinder structure and the combination of the rubber cylinders was determined.According to the contact stress between the rubber cylinder and the inner wall of the pipe and the deformation of the rubber cylinder,the hardness of the rubber cylinder with the best plugging effect was selected.(5)Completed the production of the model prototype of the stopper for oil and gas pipelines.The test results show that the upper computer and the lower computer of the stopper can communicate normally,and the control algorithm can realize the position control of the stepper motor.The model prototype lays the foundation for the production of the physical prototype of the packer.