Mechanical seal manufacturer Wear amount and service life

1、 About service life

In the mechanical seal, the main wear part is the end face of the seal friction pair, because the wear amount of the seal end face is not large under normal working conditions, such as the graphite friction pair with a balance coefficient of 0.75, the wear amount per hour in water and oil is about 0.1 μ m, that is, the wear amount is about 1 mm after 10000 hours of continuous operation, It can be seen that the wear amount of friction pair generally does not affect the service life of mechanical seal. Mechanical seals can generally be used continuously for 1~2 years, and it is no problem that they can also be used for 5~10 years in some cases. The above service life premise is that the mechanical seal operates under the allowable working conditions, such as shaft movement, runout, medium particle concentration, temperature, corrosivity and other factors.   

External factors affecting mechanical seal life:

1. Large displacement of pump shaft

2. The axial force is too large

3. The pump shaft has large deflection

4. The auxiliary flushing system is unreasonable

2、 Standards on leakage

The Technical Conditions for Mechanical Seals (JB4127.1-1999) of our country stipulates that "under the condition of reasonable selection, correct installation and use, the service life of mechanical seals is generally not less than 1 year when the sealed medium is clean water, oil and similar media. When the sealed medium is corrosive, the service life of mechanical seals is generally 6 months to 1 year. However, this limit is not applicable when the service conditions are harsh." For sealing test, the average leakage shall not exceed 5mL/h when the outer diameter of shaft (or shaft sleeve) is greater than 50mm, and the leakage shall not exceed 3mL/h when the outer diameter of shaft (or shaft sleeve) is not greater than 50mm