1. According to the pressure of the sealed cavity, it is determined that the sealing structure adopts balanced or unbalanced type, single end or double end.
2. According to the working speed, it is determined to adopt rotary or static type, fluid dynamic pressure type or non-contact type.
3. According to the temperature and fluid properties, determine the friction pair and auxiliary sealing materials, and correctly select the mechanical seal cycle protection system such as lubrication, flushing, heat preservation and cooling.
4. According to the effective space for installing the seal, it is determined to use a multi-spring or single spring or wave spring, built-in or exterior.