Gear pump gear pumps are all quality is superior and has some special applications. However, stainless steel pump, when the work will appear in a number of unexpected failures, such as downtime. We have the need to analyze the main reason for downtime, so the machine can avoid unnecessary damage to the future. Down is mainly caused by the failure of mechanical seals. Performance are mostly ineffective leakage, leakage following reasons: ① leakage static sealing surface ring main reasons are: face flatness, roughness does not meet the requirements, or surface scratches; end there between the particulate matter, resulting in two face can not be the same run; installation are not in place, the wrong way. ② compensation ring seal leakage, main reasons: gland deformation, uneven preload; not properly installed; seals do not meet quality standards; ring selection right. After the pump stops running gear requirement: ① delivery easy to crystallize, easy coagulation, sedimentation and other media easy to pump, should prevent the plug after the pump stops, and promptly washed with water pump and other media channels. ② low pump stop, when no special requirements, the pump should always be filled with liquid; suction valve and discharge valve should be kept normally open state; with double mechanical seal pumps at low temperature, liquid level controller and pump seal cavity sealing liquid grouting pressure pump should be maintained. ③ centrifugal pumps stop operating the pump of the population should be shut down valves, to be followed after the closure of the subsidiary pump cooling system valve. Accumulation of fluid within the pump discharge to prevent corrosion and the cracking. ④ high-temperature pump equipment parking shall implement the provisions of technical documents, after stopping 20 of each side plate of a car and a half laps 30min, until the pump until the temperature dropped to 50 ℃.