Hello, when it comes to the back pressure of a back pressure valve, does it refer to the pressure before the valve or the pressure after the valve? The back pressure generated by a check valve when used as a back pressure valve refers to...
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The back pressure generated by the back pressure valve refers to the pressure before the valve or the pressure after the valve? ? Is the pressure behind the backpressure valve determined by the load? ? Where does the back pressure generated by a check valve when used as a back pressure valve refer to? ? Does it refer to the pressure behind the valve plus the opening pressure of the check valve? Isn’t the opening pressure of a check valve the pressure difference across its two ends? ? ?
Let’s take a look at Baidu’s explanation of the principle behind a back pressure valve: “https://baike.so.com/doc/6306788-6520372.html””
This post was last edited by ylb913 on 2018-6-12 at 20:03. “Back” means “the rear or back side”; it’s easy to understand – it refers to the back part of the human body. So back pressure refers to the pressure at the back.
Back pressure generally refers to the pressure in front of the valve; for example, if the back pressure is 3 bar, there must be a pressure of 3 bar in front of the valve for the back pressure valve to open and allow the medium to pass through. This is the function of a back pressure valve. A check valve functions the same as a backpressure valve; it refers to the pressure in front of the valve. For example, if you want a back pressure of 3 bar, and you purchase a back pressure valve that cannot adjust the pressure – one set at 3 bar – then at the rated flow rate, there will still be an additional 1 bar of pressure behind the back pressure valve due to factors such as pipe resistance and height. As a result, the pressure in front of the back pressure valve will be 3 + 1 bar, which is higher than what you intended. If the backpressure valve can be adjusted, the backpressure can be reduced to 2 bar at this point, and then the desired pressure of 3 bar can be achieved. One final reminder: back pressure is related to flow rate; the back pressure generated by 1 L/h and 10 L/h can be quite different. Back pressure valves usually come with such a curve.
A backpressure valve is used to stabilize the pressure in front of the valve; the pressure must be higher than the set value before the valve will open； However, the flow capacity of the backpressure valve is highly dependent on the pressure behind the valve; therefore, the pressure behind the valve must also be taken into consideration when selecting the valve
Thank you, that’s great. ＾▽＾）