Analysis of rotation of pigs during pigging in gas pipeline

Pigs are designed to remove residual impurities in fluid medium pipelines, so as to increase the transport efficiency and to decrease the corrosion of pipeline. The motion attitude and the friction of pigs have a great influence on the effect of pigging. So it´s significant to do the friction assessment and motion attitude analysis after pigging is done. This paper analyzed the motion attitude of pigs during pigging in gas pipeline, and calculated the actual friction between the polyurethane pig and pipeline. This paper also discussed the method to keep the pig revolving on its own axis and the theory to control the pig´s rotation angular velocity.