gas solenoid valve

gas solenoid valve

A gas solenoid valve is a normally when open, automatic shut-off valve as per EN 161 for gas burners and gas appliances. A gas solenoid valve comprises a magnetic circuit formed with a fixed iron core, magnets and a magnetic member; a coil-holder movably provided with respect to the outer periphery of the fixed iron core and having a magnetic coil wound around itself; a sleeve accommodated within the magnets and spaced apart from the outer periphery of the fixed iron core for a predetermined distance; an actuating portion formed with the fixed iron core; the fixed iron core, the magnets and a magnetic member all fixedly covered with a molding resin from outside; and a governing portion engaged with the actuating portion.

The gas solenoid valve is suitable for most MIG & TIG welding machines. Its maximum operating pressure is 500 mbar. It is available in range of different voltages. As for its delivery, although the cost is low, the speed is very fast. The gas solenoid valve contains a micro-circuit to reduce power consumption and improve reliability. The circuit provides a pulse of current for a few seconds to open the gas solenoid valve and then automatically reduces to a much lower ‘holding’ current. This system provides a reliable on/off switching action over the full voltage range with much reduced power consumption. The gas solenoid valve is opened when it is connected from the power supply. Alternating voltage is applied and fed to the solenoid coil via a rectifier with a suppressor circuit. The blue LED lights up. The coil’s magnetic field pulls the armature with the attached valve disc upwards. The solenoid valve VAS opens. The force distribution of the supply pressure on the two valve seats is almost compensated for by having the double valve seat. The VAS is disconnected from the voltage supply. The blue LED goes out. The armature is pressed into its initial position by the closing spring. The valve closes within 1 s. The strainer in the inlet of the valve prevents deposits of dirt particles on the seat.