Tandem double seal Due to the compact, suitable for small shaft diameter, dry mechanical seal manufacturers, small axial size, mechanical seal manufacturers, and the speed of larger middle-load situations. The basic principle in the end is balanced mechanical seal selection: 1: According to the body of the seal chamber pressure, determine the sealing structure using balanced or unbalanced type reactor mechanical seal manufacturers, single face or double face like. 2: According to the working speed, determine the use of rotary or static, fluid dynamic pressure type non-contact type. 3: Depending on temperature and fluid properties to determine friction and auxiliary sealing materials, as well as the right choice lubrication, wash, heat, cooling and other mechanical seal circulation protection system. 4: Depending on the available space to install sealed determine the use of multiple springs or single spring or wave spring, built-in or externally mounted.