Newbie asks: What is the difference between PCV and PRV?
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I know their Chinese names; PCV is a self-acting pressure control valve, and PRV is a pressure relief valve. What are the specific differences between the two?
One is automatically adjustable, and the other is manually adjustable
PRV is a type of PCV; another commonly used PCV type is the back-pressure control valve, also known as a relief valve
The third floor is correct. A pressure reducing valve is used to maintain a constant pressure behind the control valve, while a self-acting control valve can keep the pressure in front of the valve constant and can be used at low pressures... In other words, a pressure reducing valve is just a part of a self-acting control valve……
Everything said upstairs is correct. Actually, the main difference is self-reliance. The self-acting type is equipped with a pressure extraction tube to draw the pressure inside the pipeline; after this pressure is balanced against that of the spring, the valve position is determined. The pressure relief valve simply controls the valve position based on the force of the spring.
As a beginner, I still don’t quite understand it. Can it be understood that way? Help take a look. PRV: Sets the pressure value to be reduced. For example, if you set the pressure to 10, and the pressure before the valve is 50, then after passing through the PRV, the pressure behind the valve becomes 40. If the pressure before the valve is 100, the pressure after the PRV becomes 90. PCV: It represents the pressure behind the valve. For example, if you set the pressure behind the valve to 50, then regardless of the pressure before the valve, the PCV will adjust automatically so that the pressure behind the valve always remains at 50. Is that what you mean?
No, just search for images on Baidu; once you see self-acting control valves and pressure reducing valves, you’ll understand……
Could an expert take a look? The paragraph below is something I found on the Internet. The analogy I used above was based on my understanding of that paragraph; I’m not sure where I went wrong in my understanding. Please give me some advice.
In the instrumentation field, pressure regulators are generally used to connect valves to air supplies. The diaphragm of membrane actuators has a maximum allowable pressure; therefore, pressure regulators are used to reduce the pressure and prevent the diaphragm from being damaged. There may be some fluctuations in the instrument air pipeline. For example, if the pressure before the pressure reducing valve is 0.8 MPa and it drops to 0.3 MPa after passing through the valve, generally there will be a slight fluctuation before the valve – say it becomes 0.7 MPa – and the pressure will decrease a little bit after the valve, but the change isn’t significant. Nevertheless, the valve is indeed pre-tensioned using springs. Self-acting control valve……Its main function is regulation, regulation, regulation… Important things are said three times; it is possible to control either the pressure before the valve or the pressure after it. Ensure that a certain pressure remains constant. Everything you said in the picture is correct, but your understanding is wrong. I suggest you take a look at the actual item – you’ll understand right away... Without seeing it in person, no matter how much you explain, it will remain confusing……