The main differences between self-acting control valves and pressure reducing valves
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1. Their purposes are different: the self-acting control valve is designed for regulation, while the pressure reducing valve serves solely to reduce pressure； 2. The pressure relief valve allows for manual adjustment of pressure; if the pressure before the valve fluctuates greatly, adjustments need to be made frequently. A self-acting control valve operates automatically based on a set, objective value, and the pressure after adjustment can be kept constant ； 3. The pressure relief valve requires manual adjustment of the pressure difference; if the pressure before the valve changes, the pressure after the valve also changes, and it cannot automatically adjust to a fixed pressure. Self-acting control valves can automatically maintain stable back pressure or pressure upstream of the valve ； 4. The main purpose of a self-acting control valve is to maintain pressure stability, whereas the primary function of a pressure reducing valve is to reduce pressure to a certain level or below ； 5. Pressure relief valves have a wider range of adjustment, whereas self-acting control valves can only regulate pressure to a constant value ； 6. Pressure relief valves have a higher adjustment accuracy, typically 0.5, whereas the adjustment accuracy of self-acting control valves is generally 8%-10% ； 7. Self-acting control valves can regulate pressure, differential pressure, temperature, liquid level, flow rate, etc., while pressure reducing valves have a relatively limited function, generally serving only to reduce pressure ； 8. Self-acting control valves can stabilize both the pressure before the valve and the pressure after it, whereas pressure reducing valves can only regulate the pressure after the valve, serving to reduce pressure ； 9. Depending on the application industry, self-acting control valves are widely used in industries such as petroleum and chemicals, while pressure reducing valves are mainly used in water supply systems, fire protection systems, heating systems, central air conditioning systems, etc.
How is the pressure set for a stand-alone control valve? How does it work?
I would like to ask about the method of adjusting a self-acting control valve, and how to check the pressure after adjustment
I would like to ask about the method of adjusting a self-acting control valve, and how to check the pressure after adjustment
There is usually a pressure gauge behind the valve. In a self-acting control valve for regulating the pressure behind it, rotating it clockwise generally increases the pressure, while rotating it counterclockwise decreases the pressure
Shanghai KeliDa Automatic Control Valve Co., Ltd. was established in 1993 and specializes in the production of self-acting control valves. These include direct-acting self-acting pressure control valves, pilot-operated self-acting pressure control valves, self-acting flow control valves, self-acting temperature control valves, combined self-acting control valves, and nitrogen seal valves.
A self-acting control valve uses the force of the fluid medium itself to control the opening and closing of the valve; it can be a pressure reducing valve that controls the pressure downstream, or an overflow valve that controls the pressure upstream. It can even be a flow control valve to regulate the pressure difference. A pressure relief valve is a control valve designed to regulate the pressure downstream; it can be a self-acting pressure relief valve that relies on the force of the fluid itself (diaphragm type, bellows type, pilot-operated type, piston type), or it can be a control valve that is operated by external power sources (electrical, pneumatic, hydraulic). Precision and control characteristics have nothing to do with this! Do not mislead the young!
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