The installation and application of mechanical seal of vacuum pump and diaphragm pump

The installation and application of mechanical seal of vacuum pump and diaphragm pump

1. The requirements of mechanical seals for machine accuracy: (take the mechanical seal of vacuum pump as an example) (1) The diameter of the shaft (or shaft sleeve) of the mechanical seal part of the device should not exceed 0.04-0.06mm in the diameter of the mechanical seal. (2) The axial movement of the rotor does not exceed 0.3mm. (3) The runout of the mechanical seal positioning end between the sealing cavity and the sealing end cover facing the surface of the shaft (or shaft sleeve) should not exceed 0.04-0.06mm at most. 2. Confirmation of seals: (1) Confirm whether the installed seal is the same as the required type. (2) Before installation, carefully check with the general assembly drawing to see if the number of parts is complete. (3) Select the mechanical seal driven by the coiled spring, and the mechanical shaft seal of the spring has left and right rotation, which must be selected according to the rotation history of the rotating shaft. 3. Installation method of seals: The installation method varies with the type of mechanical seal and the type of machine, but the installation method is almost the same. The installation process and precautions are as follows: (1) Determination of installation size: installation When the product is used, the installation size of the mechanical seal should be guaranteed according to the operation manual or sample of the product. (2) Before loading, the shaft (sleeve) and gland should be free of burrs, and the bearing should be in good condition; the seals, shaft, sealing cavity and gland should be clean. In order to reduce the frictional resistance, the part where the mechanical seal is installed on the shaft should be coated with a thin layer of oil for lubrication. Considering the compatibility of the rubber O-ring, if oil is not suitable, soapy water can be applied. The structure of the floating static ring without anti-rotation pin should not be oiled, and should be installed in the gland dry. (3) Install the static ring together with the gland on the shaft first, taking care not to collide with the shaft, and then install the moving ring assembly. The set screw of the spring seat or transmission seat should be tightened evenly in several times. Before the gland is not fixed, push the compensating ring by hand for axial compression. After loosening, the compensating ring can automatically spring back without jamming, and then lock the gland bolts evenly.