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具有长输水管的水泵正在送水时,由于电动机的电源被切断,从这瞬间开始,管道内的平均流速开始变化,同时伴随着管内压力的变化,即发生了所谓水锤现象。一、水锤危害压力下降的危害:由于管内压力下降,在外压作用下,管路被压坏而破裂。特别是当管内压力下降到负压时,如果该负压比当时的蒸汽压力小,则在该点就发生了水柱分离。当分离的水柱再弥合时,产生非常大的冲击力,而使管道破裂。压力上升的危害:当水泵、闸阀和管路的耐压力不很高的时候,就会被上升的高压所破坏。特别应该注意的是,通常水压试验
When a water pump with a long water supply pipe is delivering water, the motor’s power supply is cut off. From this moment on, the average flow rate in the pipe starts to change, and at the same time, the so-called water hammer phenomenon occurs due to the change in the pipe pressure. First, water hammer harm the danger of pressure drop: As the pressure inside the tube decreases, under the action of external pressure, the pipeline is crushed and broken. In particular, when the pressure in the pipe falls to the negative pressure, if the negative pressure is smaller than the steam pressure at that time, water column separation occurs at this point. When the separated water column closes again, a very large impact force is generated and the pipe is broken. The danger of pressure rise: When the pressure resistance of the pump, gate valve and pipeline is not very high, it will be destroyed by the rising high pressure. Special attention should be paid to the usual hydrostatic test