The maintenance of various parts of the centrifugal slurry pump seal includes the following three points:
(1) Repair of machine seal end face
The maintenance premise for machine seals made of hard alloy or silicon carbide materials is that the sealing end face is not severely worn or broken. Machine seals that have leaked during short-term operation need to be disassembled and the sealing end face cleaned.
(2) Processing of compressed springs
A larger double end machine seal is equipped with multiple small compression springs to provide elastic compensation for the dynamic ring end face of the machine seal. However, most machine seal failures are related to the compression springs. After scaling occurs inside the machine seal, the elasticity of the compression spring weakens, and even causes the spring to lose compression, resulting in the inability of the dynamic/static ring end face to fit. This fault requires cleaning and replacing the bent and damaged compression springs, and measuring the length of each compression spring to ensure that the dynamic ring of the machine seal fits the static ring end face under uniform pressure.
(3) Cleaning and inspection of shaft sleeve, replacement of rubber sealing ring
The maintenance of the machine seal must clean the scale on all components and check for deformation. Replace and assemble all rubber sealing rings in the machine seal, and conduct a static pressure test with water.
After disassembling the machine seal, it is necessary to check the damage of the disassembled parts, especially the hard alloy surfaces of the moving and stationary rings, for severe wear or breakage. At the same time, check whether the shaft sleeve or cover is deformed. If the deformation is severe, it must be repaired or replaced, and all disassembled components must be cleaned thoroughly. The assembly of the machine seal needs to maintain a clean environment to ensure that no impurities or other foreign objects fall into the machine seal during the assembly of the sealing ring and various auxiliary sealing components. After assembly, use a feeler gauge to check whether each point is uniform and ensure that the error is below 0.10mm. Measure the length of the compression spring to ensure that the length of the compression spring is consistent, and the length error can be controlled at around 2mm. If the compression spring is too long, it will cause excessive pressure on the end face of the machine seal, generate too much heat, and also aggravate the wear of the sealing end face. If the compression spring is too short, it cannot compensate and can also cause leakage. After the assembly of the machine seal, all components, especially the moving ring component, should move flexibly without jamming. The moving ring can automatically rebound under the compensation of the compression spring under pressure. After assembly, conduct a hydrostatic test to check and repair the assembly effect.