Water hammer occurs when there is a sudden power outage or when the valve is closed too quickly. Due to the inertia of the pressure water flow, a water flow shock wave is generated, just like a hammer striking, so it is called water hammer.

Water hammer in the pumping station includes starting water hammer, valve closing water hammer and pump stopping water hammer (caused by sudden power outage and other reasons). The first two types of water hammer will not cause problems that endanger the safety of the unit under normal operating procedures. The water hammer pressure value formed by the latter is often very large, causing accidents.

Water Hammer When Split Case Centrifugal Pump is Stopped

The so-called pump-stop water hammer refers to the hydraulic shock phenomenon caused by sudden changes in flow velocity in the water pump and pressure pipes when the valve is opened and stopped due to a sudden power outage or other reasons. For example, failure of the power system or electrical equipment, occasional failure of the water pump unit, etc. may cause the centrifugal pump to open the valve and stop, causing water hammer when the split case centrifugal pump stops.

The maximum pressure of water hammer when a pump is stopped can reach 200% of the normal working pressure, or even higher, which can destroy pipelines and equipment. General accidents cause "water leakage" and water outage; serious accidents cause the pump room to be flooded, equipment to be damaged, and facilities to be damaged. damage or even cause personal injury or death.

The Dangers of Water Hammer Effect

The pressure increase caused by water hammer can reach several times or even dozens of times the normal working pressure of the pipeline. The main hazards caused by this large pressure fluctuation to the pipeline system include:

1. Cause strong vibration in the pipeline and disconnection of pipe joints

2. Destroy valves, cause pipeline burst due to severe excessive pressure, and reduce the pressure of water supply network

3. On the contrary, too low pressure will cause the pipe to collapse and damage the valve and fixing parts

4. Cause the split case centrifugal pump to reverse, damage the equipment or pipelines in the pump room, seriously cause the pump room to be flooded, cause personal casualties and other major accidents, affecting production and life.