Application examples of tandem gas film mechanical seal-

Application examples of tandem gas film mechanical seal

　2018-11-12　　

Application examples of tandem gas film mechanical seal:

The pumping medium of the 3000kt/a heavy oil catalytic unit of a petrochemical company's refinery is propylene. The inlet and outlet pressures are 1.91MPa and 2.51MPa respectively. The rotation speed is 1475r/min. The original seal is a single-end mechanical seal. The leakage is Its a tricky problem. When the series air film seal is adopted, a good solution is obtained. The light hydrocarbon pump uses a series gas film seal as shown in Figure 4-24. 2000 mechanical seal

Figure 4-24 Tandem gas film seal for light hydrocarbon pump

The series gas film seal, the first level contact mechanical seal is the main seal, and the sealed medium is light hydrocarbon; the second level gas film seal is the secondary seal, and the sealed medium is mainly nitrogen and a small amount of leakage from the mechanical seal Light hydrocarbon gas. Nitrogen is introduced between the gas film seal and the main seal, the pressure is generally 0.6-0.8MPa, which greatly increases the back pressure of the main seal, and avoids the premature vapor formation of liquid and vapor mixed phases due to frictional heat between the end faces of light hydrocarbons. Causes the problem of aggravated wear, thereby prolonging the service life of the main seal. The second level seal adopts gas film seal. The light hydrocarbon gas leaked from the main seal is discharged into the torch (or exhaust gas recovery system) with nitrogen to ensure that the process medium hardly leaks to the atmosphere. It is an environmentally friendly and safe seal. The service life of this type of seal depends on the service life of the mechanical seal, generally 2 to 3 years.　　977.html,

Application of tandem gas film mechanical seal (2) Industrial application example of 　　 liquid film mechanical seal (1)