Check valve: is the check valve installed before or after the outlet valve
Classification:
Release Time：2020-10-18
A check valve, also known as a check valve, is an automatic valve. It relies on the pressure of the flowing medium in the pipeline to push the valve flap to close and open the valve. When the medium stops flowing, the check valve flap is closed, which can effectively prevent the medium in the pipeline from flowing back, and plays an important role in ensuring the safety of the pipeline.
A check valve, also known as a check valve, is an automatic valve. It relies on the pressure of the flowing medium in the pipeline to push the valve flap to close and open the valve. When the medium stops flowing, the check valve flap is closed, which can effectively prevent the medium in the pipeline from flowing back, and plays an important role in ensuring the safety of the pipeline.
Check valve according to the structure is divided into three kinds: lift check valve, swing check valve and butterfly check valve. Lift check valve can be divided into vertical and straight-through two. Swing check valve is divided into single disc, double disc and multi-valve three. Butterfly check valve is divided into butterfly type double disc, butterfly type single disc, the above several kinds of check valve in the connection form can be divided into threaded connection, flange connection, welding and wafer connection four kinds.
Install a check valve to ensure the flow direction of water in the pump to ensure the normal operation of the pump. Therefore, regarding the installation position of the check valve, whether it is installed before or after the water pump, there are two situations:
One is the end of the vertical suction pipe installed in front of the pump, also called the bottom valve. The purpose is to fill the pump once without pumping water, because when there is no water in the pump and there is no water in the suction pipe in front of the pump, the pump can only be in an idle state and cannot pump water, so the pump must be filled with water to pump water. The installation of this water pump is a method higher than the liquid level, also known as the negative pressure method.
The other is mounted on the back of the pump. This installation method is that when the liquid level is higher than the water pump, the water pump can be conveniently started and stopped without closing the water pump outlet valve, especially for the main control water pump system to prevent backflow.
In order to check the check valve, the check valve must be installed at the outlet of the pump and before the outlet control valve. Usually, one side of the pump outlet is a soft connection (shock absorber), then a check valve, and then a shut-off valve (such as butterfly valve, gate valve, shut-off valve, etc.).
1. Install the check valve first, and then install the gate valve or butterfly valve
Advantages: It can protect the check valve, especially in parallel pumps. When one pump is not started, its outlet door is closed, and when the other pump is started, the impact force is borne by the gate valve or butterfly valve. After the one-way valve fails, the inlet and outlet valves can be closed to isolate the system for maintenance.
Disadvantages: Who will protect the gate valve or butterfly valve? Sometimes the valve plate of the butterfly valve is damaged.
2. Install the gate valve or butterfly valve before installing the check valve
Advantages: It can protect the butterfly valve or gate valve, and the impact force is borne by the check valve.
Disadvantages: Who will protect the check valve? The check valve opens and closes by pressure difference. If the main pipe pressure is high, turn it off and turn on the pump pressure. If the flow used is unstable, the check valve will switch repeatedly, which will affect the life of the check valve. In addition, the check valve is damaged, especially the parent control system is damaged, and it can be repaired after closing the system.
Next Page
Related News
2026/02/28
Contact Information
+86 27-8970 8339
Address: No.5, Zhengjie, Shuangliu Street, Xinzhou District, Wuhan City, Hubei Province