Precautions for Maintenance of Mechanical Seals for Pumps

(1) Do not install the dynamic ring seal tightly during installation. If the installation is too tight, the first is to intensify the wear between the sealing ring and the bushing and cause premature leakage. The second is to increase the resistance of the moving ring to adjust axially and move it. When the working conditions change frequently, it cannot be adjusted timely. Third, the spring is excessive. Fatigue is easy to damage; the fourth is to make the dynamic ring seal deformation, affecting the sealing effect.

(2) Do not install the static seal ring too tightly during installation. The static ring seal is basically in a stationary state, and the relatively tight seal effect is better, but too tight is also harmful. Firstly, it causes excessive deformation of the static ring seal, which affects the sealing effect. Second, the material of the stationary ring is mainly graphite. It is generally brittle. Excessive stress can easily cause fragmentation. Third, it is difficult to install and disassemble during the maintenance process, and can easily damage the static ring. 

(3) The sealing bellows or spring compression mediation is moderate. The greater the compression is, the better the sealing effect is. If the bellows or the spring is compressed too much, it can cause the friction pair to wear abruptly and burn instantly. Excessive compression will cause the spring to lose its ability to adjust the end face of the moving ring, resulting in seal failure.

(4) Do not overlock the sleeve lock nut. Leakage between the pump sleeve and the pump shaft is a common case of failure leakage from the mechanical seal of the pump. The failure of the shaft lock to lock the lock net is not the only cause of shaft leakage. There are many factors that lead to leakage between shafts. For example, shaft seals are damaged, misaligned, there are impurities in the shaft, and the contact surface is damaged. Overlock of the shaft sleeve lock will lead to premature failure of the inter shaft gasket. On the contrary, the lock shaft will be properly locked so that the shaft gasket always maintains a certain degree of compression and elasticity. When the pump is running, the lock mother will automatically lock in time, so that the shaft will always be locked in a good sealed state.

(5) Correctly select the mechanical seal structure and material according to the different working conditions of the pump and the nature of the medium. Only the correct choice of sealing structure and material can guarantee the sealing effect. Mechanical seals have high temperature resistance, low temperature resistance, high pressure resistance, corrosion resistance, resistance to mechanical seals of granular media, etc. Mechanical seals of different structural types and materials should be selected according to different uses.