Does the diameter of the air line for the pneumatic actuator affect the valve’s opening and closing time?
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I’ve always had a question: there are many solenoid valves (1/4) at the site that are connected to air circuits equipped with air control valves (1/2). Why isn’t air supplied directly through the solenoid valves? According to the continuity equation, shouldn’t the flow rate be the same? Is it perhaps due to high resistance in the small pipes, or is there some other reason? Given a constant main air line, does the diameter of the pipe downstream of the air source ball valve affect the speed at which the valve opens and closes, and to what extent? Are those speed-up accessories for air circuits truly effective?
Theoretically, it has an impact, but the actual effect is minimal. The opening and closing speed of the valve depends only on the flow rate of the gas supply; the higher the pressure of the gas supply, the faster the opening and closing speed. At the same gas supply pressure, the greater the force resisting the valve’s movement, the slower its opening and closing speed.
Air supply fitting 1/2, air-controlled valve 1/2, solenoid valve 1/4; the solenoid valve is used to control the air-controlled valve (pneumatic amplifier), which helps to speed up the valve’s operation. If the gas supply fitting is also 1/4, then it makes no sense to add an amplifier.
The fluid continuity equation states that the mass of fluid flowing through any cross-section of a pipe or duct per unit time remains constant. Using a flow rate of 1/2 for slower speeds and 1/4 for faster speeds, with the flow rate remaining constant, can it really speed up the actions?
The opening and closing speed of the valve is related to the air supply pressure and flow rate; if the flow rate is insufficient, the valve does not open or close properly, and when the pressure is low, the valve moves slowly or fails to move at all
I conducted an experiment, and it was indeed found that the diameter of the gas pipeline has a significant impact on the valve’s response time. So more explanations were given: during the inflation phase, there are two processes depending on the critical ratio (it was observed on site that the valve first opens and then moves more slowly); when the value is below the critical ratio, the flow rate remains constant, while it changes only when the value is above the critical ratio