Gear pump gear pumps in all belong to the more excellent quality and have a special range of applications. However, stainless steel pumps also have some unexpected malfunctions at work, such as downtime. We need to analyze the main reasons for downtime, so as to avoid unnecessary damage to the machine in the future. Downtime is mainly caused by the failure of the mechanical seal. Gear pump stop running maintenance and seal failure. Mainly due to the failure of the performance of the leak, there are several reasons for leakage: ①static and dynamic ring sealing surface leakage, the main reasons are: flatness of the end surface, roughness does not meet the requirements, or scratches the surface; particulate matter between the ends, resulting in two Face can not be the same run; installation is not in place, the way is not correct. ② compensation ring seal leakage, mainly due to: gland deformation, uneven pre-tightening; installation is not correct; seal quality does not meet the standards; seal selection wrong. Vortex flowmeter gear pump stop running after the request: ①easy to transport, easy to coagulate, easy precipitation and other media pump, stop the pump to prevent clogging, and timely flush with water or other media pumps and pipes. ② high-temperature pump should be stopped according to the provisions of technical documents, after parking should be partial 20 -30 30min half a turn until the pump temperature dropped to 50 ℃ so far. ③ cryogenic pump parking, when no special requirements, the pump should always be filled with liquid; suction valve and the discharge valve should be kept normally open state; the use of double-end mechanical seal of the cryogenic pump, liquid level controller and seal the liquid seal chamber The pump grouting pressure should be maintained. ④ Centrifugal pump should stop running after the pump population valve, to be cooled and then turn off the auxiliary system valves. Exhaust the liquid stored in the pump to prevent corrosion and cracking.