Research On The Key Technologies Of Emergency Repair In The Crossing Section Of Lancang River In China-Myanmar Natural Gas Pipeline

The Sino-Burmese Pipeline Minjiang River crossing project is an important cross-over control project for the Sino-Myanmar pipeline.The emergency repairs for emergencies are extremely difficult due to geographical location and the complex and changeable geomorphology and special environment surrounding it.The accident emergency treatment technology and maintenance equipment for general oil and gas pipelines are not fully applicable to the Lancang River crossing project.In particular,there is no mature experience available for reference for the pulling and hoisting of pipes and machines on large spanning bridges.This subject has analyzed,designed and optimized the maintenance equipment for the pressure plugging and lifting technology,and provided the basis for solving the problems in the above-mentioned maintenance process.After on-site exploration and literature research,we found that when the natural gas pipelines across the Lancang River in the Sino-Burmese pipeline leaking,the emergency repair of the gas pipelines across the segment has the problem of not being able to quickly stop the pressure plugging and repairing equipment cannot be hoisted onto the bridge.In order to solve the above problems,based on the previous research,mechanics and finite element theory,using ANSYS APDL software to study the above issues,and the actual occurrence of cross-section natural gas pipeline corrosion perforation events also were analyzed,the main research content as follows:1.on the basis of the field investigation,the difficulties of the natural gas pipeline maintenance in the Lancang river crossing section are analyzed and determined by combining the characteristics of Lancangjiang River crossing project itself,the geographical location and the surrounding terrain.2.on the basis of the difficulty analysis,the adaptability of the technology applied to the leakage blocking of natural gas pipeline in Lancangjiang River is analyzed,and the technical factors such as the applicable conditions,the scope of application and the safety requirements of each technology are clarified.3.Based on the adaptability of pressure plugging technology,combined with the theory of material mechanics,the specific dimensions of the fixture are calculated,fixtures are designed,combined with finite element theory,the fixture leakage system is analyzed and verified using ANSYS software,and the difficulty of blocking leakage in the process of maintenance is solved.4.According to the emergency repair process,the emergency repair equipment should be hoisted to the bridge for maintenance after the temporary pressure plugging is completed.Therefore,the adaptability of all kinds of hoisted equipment is analyzed,including its advantages and disadvantages,the applicable slope and so on.5.On the basis of material and statics mechanics,the masts are determined by mechanical analysis to determine the size of mast,and the mast is simulated and analyzed with ANSYS.The safety of mast is analyzed and verified,so as to solve the difficulties that the repair equipment can not be hoisted to the bridge during the maintenance process.6.Based on the designed clamp and mast,the emergency disposal of the natural gas pipeline after the Lancang river crossing section was studied.The clamp and mast were applied to the site,providing reference for the emergency disposal of the leakage of natural gas pipeline in the Lancang river crossing section.This thesis is based on the scene,using mechanics,finite element theory,etc.,to solve the problem that the natural gas pipelines of the Sino-Burmese pipeline crossing the Lancang River cannot be plugged quickly,and that the maintenance equipment cannot be hoisted onto the bridge.This thesis can be a reference for the on-site maintenance.