In order to achieve rapid plugging of oil and gas pipelines,a robot and an inflatable plugging device that can be used for rapid plugging and diversion of pipelines were designed.The plugging device consists of an airbag and a diversion pipe.After the airbag inflates and expands,it compresses the inner wall of the pipeline and the outer wall of the diversion pipe to form a sealing area,so that the liquid will not leak from the pipe cracks,but will flow through the intermediate diversion pipe,realizing the plugging and diversion functions.Four airbag models with different structures were designed,and the maximum von Mises stress and contact stress under different pressure were studied.The results show that when the chamfer of the contact edge with the tube wall is a right angle,the inside of the airbag is a circular hollow structure,the airbag has the maximum contact stress and the best contact sealing effect,it also has the smallest stress,and the strongest pressure bearing capacity.