Normal operation and maintenance of mechanical seals

1. Preparations and precautions before starting
a Comprehensively check whether the mechanical seals, accessories and pipelines are installed completely and meet the technical requirements.

b Before starting the mechanical seal, perform a static pressure test to check whether the mechanical seal has leakage. If there is a lot of leakage, find out the cause and try to eliminate it. If it is still ineffective, disassemble it for inspection and reinstall it. The general static pressure test pressure is 2-3 kg/cm2.

c Turn the pump according to the direction of rotation to check whether it is light and even. If the turn is difficult or does not move, check whether the assembly size is wrong and whether the installation is reasonable.

2. Installation and shutdown
a Before starting, the sealing chamber should be filled with liquid. When conveying solidified media, steam should be used to heat the sealing chamber to melt the media. Turning must be done before starting to prevent the soft ring from breaking due to sudden start.

b For mechanical seals that use an external pump oil sealing system, the oil sealing system should be started first. The oil sealing system should be stopped last after parking.

c After the hot oil pump stops operating, the cooling water of the oil seal chamber and the end face seal cannot be stopped immediately. The cooling water should be stopped only when the oil temperature at the end face seal drops below 80 degrees to avoid damaging 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 continuous operation for 4 hours, 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, the phenomenon of vacuuming should be avoided to avoid dry friction of the sealing surface and damage to the seal.

The mechanical seal itself is a high-demand precision component with high requirements for design, machining, and assembly quality. When using a mechanical seal, various factors for using the mechanical seal should be analyzed to make the mechanical seal suitable for the technical requirements and medium requirements of various pumps and have sufficient lubrication conditions, so as to ensure long-term and reliable operation of the seal.