The second issue of Tianjin Equipment Management in 2013, sponsored by Tianjin Equipment Management Association, gave a special introduction to our company.

The main issues that should be paid attention to when selecting and using mechanical seal structure are:

1) Sealing working pressure: Generally, in mechanical seals, when the working pressure is higher than 3Mpa, the double-end face balanced structure seal is used, and when it exceeds 15Mpa, multi-stage sealing can be used. Unbalanced seals can be used below 0.7Mpa. For occasions with low viscosity and poor lubricity, a balanced seal is used under 0.2-0.3Mpa pressure.

2) Peripheral speed: For high-speed seals (peripheral speeds higher than 25m/s), static seals should be used.

3) Temperature: The temperature of the sealing medium is below 80°C, and general mechanical seals can be applied. The mechanical seal with a temperature higher than 150°C is a high-temperature seal, often using a welded metal bellows structure. The seal below -20°C is an ordinary low temperature seal, and the seal below -50°C is a cryogenic seal.

4) Axle journal: The seal with a journal larger than 120mm is a large journal seal, and a small journal seal with a journal smaller than 25mm.

5) Media properties: For weakly corrosive media, an internal seal can be used, and for more corrosive media, an external seal can be used. For flammable, explosive and toxic products, double-end or multi-stage sealing should be used.