Abstract: The storage and transportation system of a company has several cold vacuum residuum pumps in which the medium is of high viscosity and high solid content, and it is difficult to increase the upper and outer flushing system. So the service life of the vacuum residuum pump machine seal is generally short. Through analyzing and testing a variety of optimization schemes, it is finally determined to change the original single mechanical seal into double dry gas seal. The practical application results show that the technology can solve the problem of frequent leakage of the mechanical seal of vacuum residuum pump effectively.

Key words: vacuum residuum pump, mechanical seal, dry gas seal, zero leakage