Explosion proof solenoid valves have a normally closed type: when the solenoid coil is energized, the moving iron core is attracted, the pressure relief hole is opened, and the pressure acting on the upper part of the main valve core is reduced, thereby relying on the pressure difference to push the main valve core upward and open the valve; When the electromagnetic coil is powered off, the moving iron core falls due to its own weight and the action of the moving iron core spring, closing the pressure relief hole and creating pressure on the upper surface of the main valve core. With the addition of the main valve core pressure spring and its own weight, the main valve core falls to the valve port and the valve closes. Normally open: When the electromagnetic coil is powered on, the pressure relief hole forms a closed state opposite to normally closed, and the valve is closed. When the electromagnetic coil is powered off, the pressure relief hole forms an open state opposite to the normally closed state, and the valve opens.