循环水泵出口安装止回阀的问题（The problem of installing a check valve at the outlet of the circulating pump）.docVIP

循环水泵出口安装止回阀的问题（The problem of installing a check valve at the outlet of the circulating pump） In the water supply and drainage system, it is necessary to set a check valve at the outlet of the water pump or drain pump. Because these systems are open systems, they carry water from low to high, or send water from low pressure to high pressure. When the pump is stopped, if there is no check valve, the water will flow back. The heating system is a closed system, the role of circulating water pump is to overcome the network cycle resistance, so that water circulation in the network. When the pump stops working, the pressure on both sides of the pump is equal, and no reverse flow will occur. Therefore, the installation of the check valve will only increase the network resistance, unnecessary consumption of electricity, without any effect. The heat source and the outlet of circulating water pump heat exchanging station are not set up a non-return valve, but the water supply system and water supply system, the pump outlet check valve should be set up. For parallel installation of multiple pumps. According to the centrifugal pump operating procedures, do not work the pump should be shut off the pump inlet and outlet valves, without the need to isolate a check valve function, check valve in the heating system is closed and not redundant equipment make an unnecessary move, said heating system check valve can be canceled, open system can not be canceled, such as feed water pump the export of steam boiler check valve can not be canceled, but on hot water boiler feedwater pump outlet closed heating system check valve can be cancelled. There are 10 seconds but reversed after the pump is stopped, but the speed is not too fast, this is because the fluid has the momentum and the degree of compression expansion natural retraction pressure relief and pipeline system, there is no sign of acceleration. Here we have to mention the water hammer effect. What is the water hammer effect and t