The filter piston type electromagnetic control valve is composed of main valve, solenoid pilot valve, needle valve, ball valve and micro filter. The valve can be opened and closed remotely through the solenoid pilot valve. When the valve feeds water from the inlet end, the water flows through the needle valve and enters the upper chamber control room of the main valve. When the solenoid pilot valve is opened, the water in the control room flows out through the solenoid pilot valve and ball valve. When the opening of the ball valve is greater than that of the needle valve, the pressure in the control room of the upper chamber of the main valve becomes low, and the main valve is in full open state; when the solenoid pilot valve is closed.
The water in the control room of the upper chamber of the main valve can not flow out, so the pressure in the control room pushes the piston to close the main valve; the product uses the pilot valve to control the opening and closing of the valve, which can reflect accurately and quickly. It adopts the three-way solenoid valve and is easy to maintain. It is installed on the pipes of various water supply systems.

    There are two types of diaphragm type and piston type. The main components are a main valve and its attached pipe, pilot valve, needle valve, ball valve and pressure gauge. When the pressure water in the control chamber above the diaphragm (piston) is discharged to the atmosphere or downstream low-pressure area, the pressure value acting on the bottom of the valve disc and under the diaphragm is greater than the pressure value above. Therefore, the main valve disc is pushed to the fully open position, When the pressure in the control chamber above the diaphragm (piston) cannot be discharged to the atmosphere or downstream low area, the pressure value acting on the diaphragm (piston) is greater than the pressure value below, so the main valve disc will be pressed to the fully closed position. When the pressure value in the control chamber above the diaphragm (piston) is between the inlet pressure and the outlet pressure, the main valve disc is in the regulating state.

Part name	texture of material
Valve body and cover	Cast iron, cast steel, stainless steel
valve seat	Tin bronze, stainless steel
Disc	Carbon steel, stainless steel+NBR
Stem	Aluminum green steel, chromium stainless steel
piston	Chromium stainless steel+NBR
filter screen	stainless steel
Spring	stainless steel

DN	50	65	80	100	125	150	200	250	300	350	400
L	250	280	335	380	425	480	750	660	740	810	860