What are the precautions for oil seals?

1. Preparations and precautions before starting
a. Comprehensively check the mechanical seal, whether the attachments and pipeline installation are complete, and whether they meet the technical requirements.
b. Before starting the mechanical seal, perform a static pressure test to check whether the mechanical seal is leaking. If there are too many leaks, find out the cause and try to eliminate it. If it is still invalid, it should be disassembled, inspected and reinstalled. Generally, the static pressure test pressure is 2~3 kg/cm².
c. Rotate the pump to the crank to check whether it is brisk and even. If the crank is difficult or does not move, check whether the assembly size is wrong and whether the installation is reasonable.

2. Installation and shutdown
a. Keep the sealed cavity filled with liquid before starting. When transporting solidified media, steam is used to heat the sealed cavity to melt the media. The car must be cranked before starting to prevent the soft ring from breaking due to sudden start.
b. For mechanical seals that use the external oil sealing system of the pump, the oil sealing system should be activated first. The oil sealing system is finally stopped after stopping.
c. After the hot oil pump is shut down, the cooling water in the oil seal cavity and the end face seal cannot be stopped immediately. The cooling water should be stopped when the oil temperature at the end face seal drops below 80 degrees to avoid damage to the sealing parts.

3. Operation
a. If there is a slight leakage after the pump is started, it should be observed for a period of time. If the leakage does not decrease after 4 hours of continuous operation, the pump should be stopped for inspection.
b. The operating pressure of the pump should be stable, and the pressure fluctuation should not exceed 1 kg/cm².
c. During the operation of the pump, pumping down should be avoided to avoid dry friction on the sealing surface and damage to the seal.
d. The sealing condition should be checked frequently. During operation, when the leakage exceeds the standard, the heavy oil is not more than 5 drops/min, and the light oil is not more than 10/min. If there is no improvement trend within 2-3 days, the pump should be stopped to check the sealing device.