Mechanical overheating of the slurry pump can cause its seal to failThe main reason for the failure of the mechanical seal of the slurry pump is the mechanical tolerance of the slurry pump, and the mechanical seal of the equipment needs to be assembled correctly. The shaft must have the proper surface roughness and the correct graduation. However, manufacturers rarely provide service data that is critical to the device. The dimensional accuracy and shape position of the mechanical seal must meet the requirements of the drawing, too large will lead to premature failure of the seal. The slurry pump mechanical seal surface is reversed. When the sealing surface is opened, the solid particles in the medium enter the sealing surface under the pressure of the liquid. When the sealing surface is closed, these solid particles are embedded in the surface of the soft ring (usually the graphite ring) and effectively become a "grinding wheel". "It can damage the appearance of the hard ring.
When repairing mechanical seals, 85% of seal failures are not caused by wear, but have leaked before wear. Because the moving ring or rubber ring is fixed on the shaft (sleeve), when the shaft moves in series, the moving ring can not cooperate in time, so that the sealing surface is opened, and the sealing surface is closed with lag, so that the solid particles enter the sealing surface, and at the same time, there is between the solid particle shaft (sleeve) and the sliding part, which affects the sliding of the rubber ring or the moving ring. In addition, the medium will also produce crystals in the friction part of the rubber ring and the shaft (sleeve), and there will be solid substances in the spring, which will cause the sealing surface to open and the slurry pump will be mechanically overheated due to the heating of the sealing surface, and the working temperature of the rubber ring should be lower than the design specification. The secondary temperature of fluororubber and PTFE is 216, and the use temperature of nitrile rubber is 162. While they can accept higher temperatures, the heat generated by the sealing face is higher, so the rubber ring is constantly vulcanized. It loses its flexibility and leakability. The heat between the sealing surfaces will also cause crystallization of the medium, such as carbon deposits, resulting in the jamming of the sliding parts and the condensation of the sealing surfaces. Moreover, some polymers coke due to overheating, and some fluids lose lubrication due to overheating, or even flash fires. In addition to changing the medium, overheating increases its corrosion rate. Cause deformation of metal parts, alloy surface cracks, and coating parts, and choose a balanced mechanical seal to reduce the specific pressure and prevent overheating.