Abstract: At present,it is the most economical and reliable way to transport oil and gas by subsea pipeline in offshore oilfield. With the increase of the operation time of the subsea pipeline,problems such as corrosion,impurity deposition and scaling of the pipe wall are easy to occur. The pigging can not only effectively remove the impurities in the subsea pipeline,but also understand the corrosion damage in the subsea pipeline. SolidWorks software is used to simulate the pigging process of the mechanical pig in the subsea pipeline with underwater tees. The results show that forward pigging has no risk of pig sticking,and the pig can automatically realign after deviation,while reverse pigging has risk of pig sticking. The field test results show that the foam pig is intact and 15 kg of impurities are removed when the foam pig is used for reverse pigging. After pigging,the pressure difference between the inlet and outlet decreases from 500 kPa to 110 kPa,and the effect is obvious.

Key words: Solidworks simulation, simulation experiments, subsea pipeline, pigging operation