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Idle operation of a centrifugal pump can cause significant damage to the water pump; it may lead to cavitation or damage to the mechanical seal, among other problems. Today, together with the expert, we will explore the causes and consequences of centrifugal pump idling. Reasons for idling: Insufficient medium at the pump’s inlet, inadequate water inlet pressure, a blocked water inlet pipe in the pump, or air remaining inside the pump chamber that has not been removed. The hazards of idling have the following main effects on water pumps: (1) Due to the large amount of gas present inside a pump that is idling, cavitation can easily occur, causing damage to the pump body and its flow components ； (2) Without liquid lubrication from a mechanical seal or packing seal, dry friction can easily cause wear ； (3) The balance disc of a idling multi-stage centrifugal pump receives no lubrication, and as a result the balance disc will be damaged very quickly ； (4) When the water pump runs idle without any liquid, the rotor components and the pump body heat up, and since there is no cooling, thermal expansion and contraction can easily cause certain gaps (such as those in the sealing rings) to become stuck. Early warning and maintenance: (1) Adjust the various clearance areas of the centrifugal pump; increase them within acceptable limits to prevent seizure ； (2) The shaft of the centrifugal pump is subjected to special treatment processes such as quenching and tempering, heat treatment, etc., to increase its hardness; materials with low flexibility are used to prevent excessive swinging during idling, which could lead to seizure ； (3) Use mechanical seals and packing chambers that do not require lubrication with a liquid medium ； (4) Use sealed, self-lubricating bearings that require no oiling ； (5) The pump chamber of the horizontal self-priming centrifugal pump has a larger volume compared to other centrifugal pumps, providing a space for storing water. Before a self-priming centrifugal pump can operate properly, the chamber must be filled with liquid. There is a priming period before it starts working, during which air is continuously expelled from the pump. This period constitutes partial idling ； (6) Install an idling detection system. Modern equipment is used for real-time monitoring of water pumps; when a centrifugal pump starts to run idle, an alarm is triggered and the pump shuts down automatically, thereby protecting the safety of the unit.