Analysis of the failure of the mechanical seal of the sanitary centrifugal pump ③

The sliding groove on the surface of the sealing surface and the gaps in the end faces when the end faces are attached lead to the failure of the sealing element. The main reasons are:　　

1. The liquid medium is not clean and has tiny hard particles. It slides on the sealing surface at a very high speed, which will scratch the surface of the end surface and cause it to fail.
2. The transmission parts of the sanitary centrifugal pump have poor coaxiality. After the pump is turned on, the end face is swayed and rubbed once per revolution, and the moving ring runs out of concentricity, causing the end face to vaporize, overheating and abrasion.　　
3. The frequent occurrence of hydraulic characteristics of the liquid medium causes the pump unit to vibrate, causing the sealing surface to be misaligned and fail.

The corrosion of the sealing element by the liquid medium, stress concentration, soft and hard material coordination, erosion, auxiliary seal 0-ring, V-ring, concave ring and liquid medium incompatibility, deformation, etc. will cause damage and failure of the mechanical seal surface, so The damage form must be analyzed comprehensively to find the root cause to ensure the long-term operation of the mechanical seal.