Abstract: Based on the operation actions of double-directional & self-sealing in actual use, four processes, namely connection, open-door, close-door, and seperation have been differentiated in this article. In order to calculate the operational force or operational moment of force, four kinetics models have been established respectively, and digital simulation has also been completed. The result shows that the self-sealing coupler has some features, such as low operational force, fast operational speed, and high operational efficiency.