Basic principles of mechanical seal selection

There are two types of mechanical seals, wet and dry, with contact and non-contact types. Contact wet seal is referred to as 'mechanical seal', contact dry seal is referred to as 'dry running seal', and non-contact dry seal is referred to as 'dry gas seal'. When selecting mechanical seals for mixing equipment, the following requirements should be selected.

(1) Liquid lubricated (wet) contact mechanical seal

(2) Provisions for dry mechanical seals (contact and non-contact).

(3) The mechanical sealing material shall be selected according to the following requirements:

1. It should meet the requirements of corrosion resistance. /2, should meet the requirements of operating temperature.

3. The pv value of the dynamic and static ring materials should be less than or equal to the allowable [pv] value (except for non-contact dry gas seals).

4. It should meet the requirements of current laws and regulations of the country or industry (for example: the food and pharmaceutical industries require non-toxic materials).