Working principle of pilot solenoid valve
When energized, the electromagnetic force opens the pilot hole, the pressure in the upper chamber drops rapidly, and a pressure difference between the lower part and the lower part is formed around the closing member. The fluid pressure pushes the closing member upward to move the valve to open; when the power is off, the spring force closes the pilot hole. The inlet pressure through the bypass hole rapidly forms a lower low and high pressure difference around the valve member, and the fluid pressure pushes the closing member downward to close the valve.
Features: The upper limit of the fluid pressure range is high, it can be installed arbitrarily (customized), but the fluid pressure difference condition must be met.