Rotary Part Of Customized AS-B275 Metal Bellow Mechanical Seal

Background Knowledge：
What are the failure forms of mechanical seals due to their own parts’ problems?

The sealing surfaces themselves also provide signs of seal failures. For example, when vibrating, there will be wear marks on the transmission parts. If the marks are not obvious, it is generally caused by improper assembly of the mechanical seal.

There are many internal pores in the graphite ring (as rotary face) of poor quality. 

The scars on the inner cylindrical surfaces of the sealing surfaces are probably caused by foreign debris entering the sealing surfaces or improper installation of the mechanical seal. Most of the annular grooves on the sealing surfaces are caused by the deposition of solid particles on the sealing surfaces of the mechanical seal.

The crack（s） of the graphite ring (rotary face) is caused by vibration of the transmission part, expansion of the rubber ring or internal stress of the graphite ring itself, while coking is caused by high temperature.

Usually overheating of the hard rings (stationary seats ) surfaces will cause severe wear of the sealing rings, such as those of uncooled vertical pumps. Besides，high temperature, high pressure, excessive spring compression or excessive shaft movement will cause transitional wear of the sealing surface（s） of mechanical seals.