Working Principle of the 2W Normally Closed / Normally Open Solenoid Valve

The 2W solenoid valve is an indirectly opened, single-disc globe valve that uses electromagnetic force to directly open the pilot valve and then opens the main valve through the medium pressure difference. Depending on whether it is open or closed when energized, the 2W solenoid valve can be divided into normally closed and normally open types.

The working principle of the normally closed solenoid valve is: before receiving an electrical signal, the solenoid valve is in the closed state. After the coil of the high-temperature normally open solenoid valve is connected to the electrical signal, it generates a corresponding magnetic field; under the action of the electromagnetic force, the movable iron core and the fixed iron core attract each other, and the movable iron core moves upward, driving the valve stem to overcome the spring force and move up, so that the sealing surface of the valve stem separates from the pilot valve seat and the pilot valve opens. The medium in the upper chamber of the diaphragm flows through the pilot valve to the valve outlet. Because the diameter of the medium inlet passage of the upper chamber of the diaphragm (the diaphragm damping hole) is smaller than the diameter of the pilot valve passage, the incoming medium flow is less than the flow to the outlet; after a certain time, the medium pressure in the upper chamber of the diaphragm continuously drops. When the difference between the medium pressure in the upper chamber and the medium pressure in the lower chamber of the diaphragm reaches a certain value, the diaphragm is lifted up by the pressure difference, the main valve opens, and the valve opens. After the solenoid coil cuts off the electrical signal, the magnetic field generated by the energization disappears, and the electromagnetic force disappears; under the action of the spring force, the movable iron core moves downward, driving the valve stem to move down, so that the sealing surface of the valve stem is pressed tightly against the pilot valve seat to achieve sealing, and the pilot valve closes. The medium flows through the diaphragm damping hole to the upper chamber of the diaphragm; after a certain time, the medium pressure in the upper chamber of the diaphragm rises to a certain value, pushing the diaphragm to move down, the main valve closes, and the valve closes.

The working principle of the normally open solenoid valve is: before the electrical signal is connected, the solenoid valve is in the open state. After the solenoid coil is connected to the electrical signal, it generates a corresponding magnetic field; under the action of the electromagnetic force, the movable iron core and the fixed iron core attract each other, and the movable iron core moves downward, driving the valve stem to overcome the spring force and move down, so that the sealing surface of the valve stem is pressed tightly against the pilot valve seat to achieve sealing, and the pilot valve closes. The medium flows through the diaphragm damping hole to the upper chamber of the diaphragm; after a certain time, the medium pressure in the upper chamber of the diaphragm of the liquid-use normally open solenoid valve rises to a certain value, pushing the diaphragm to move down, the main valve closes, and the valve closes. After the solenoid coil cuts off the electrical signal, the magnetic field generated by the energization disappears, and the electromagnetic force disappears; under the action of the spring force, the movable iron core moves upward, driving the valve stem to move up, so that the sealing surface of the valve stem separates from the pilot valve seat and the pilot valve opens. The high-pressure medium in the upper chamber of the diaphragm flows through the pilot valve to the valve outlet. Because the diameter of the medium inlet passage of the upper chamber of the diaphragm (the diaphragm damping hole) is smaller than the diameter of the pilot valve passage, the incoming medium flow is less than the flow to the outlet; after a certain time, the medium pressure in the upper chamber of the diaphragm continuously drops. When the difference between the medium pressure in the upper chamber of the valve cup and the medium pressure in the lower chamber reaches a certain value, the diaphragm is lifted up by the pressure difference, the main valve opens, and the valve opens.