Two-way solenoid valve working principle _ two-way solenoid valve structure

- Oct 09, 2019-

First, the characteristics of two-way solenoid valve

1. The valve is sealed with stainless steel piston to completely prevent leakage;


2. Within the scope of use pressure, the valve does not distinguish between import and export, that is, the import is the export, and the export can be used normally when the import;


3. The coil adopts an exclusive high-power coil to ensure the rapid opening and closing of the two-way solenoid valve;


4, the internal processing of special processing 304 stainless steel springs, so that when the medium flows from the outlet to the inlet, it can also be completely closed;


5. The valve adopts a direct-acting structure to meet the working conditions with low operating pressure.


image


Second, the technical parameters of the two-way solenoid valve (low pressure type)

Caliber: DN10-DN500


Power supply voltage: DC6V-DC220V, AC12V-AC220V


Coil power: 120W, 150W, 200W


Working pressure: DN10-DN50: Forward: 1MPa; Reverse: 0.6MPa


DN65-DN200: Forward: 0.8MPa; Reverse: 0.5MPa


DN250-DN500: forward: 0.5MPa; reverse: 0.2MPa


Connection method: internal thread, flange, welding


Use medium: water, gas, oil, steam, high temperature oil, etc.


Medium temperature: -200 °C - 0 °C, -60 °C - +80 °C, -20 °C - +80 °C, -5 °C - +80 °C, -5 °C - 120 °C, 0 °C - +200 °C, 0 °C —+600°C


Body material: stainless steel 304, stainless steel 316, carbon steel


Protection level (optional): waterproof (IP65), anti-corrosion, explosion-proof (ExdIICT5)


Wiring method: plug type, lead type, junction box


Control method: normally closed


Additional features (optional): with manual function, with signal feedback, with filtering


Leakage level: zero leakage


image


Third, two-way solenoid valve (low pressure type) working principle

Normally closed: The two-way solenoid valve is normally closed; when the coil is energized, the solenoid valve is opened, and after the power is turned off, the solenoid valve is closed. When the solenoid valve is in the open state, the inlet pressure is greater than the outlet pressure, and the medium flows from the inlet end to the outlet end; when the outlet pressure is greater than the inlet pressure, the medium flows from the outlet end to the inlet end. And regardless of whether the medium pressure is greater than the outlet end of the inlet end or the outlet end is greater than the inlet end, the solenoid valve can cut off the medium after the power is turned off.


image


Fourth, the structure of the pilot type two-way solenoid valve

The pilot type two-way solenoid valve is mainly composed of a valve body, a normally closed main valve flap, a normally open main valve flap, a pilot valve flap, an electromagnet and the like. The main valve flap and the piston are connected by a ram (Fig. 1), which is characterized by an internal spring-free elastic reset element, which completely switches the gas passages by aerodynamic force and electromagnetic force, and controls the air supply of the normally open cavity and the normally closed cavity. Sealed, the maximum working pressure is 5.0MPa.


When the electromagnet is in the de-energized state, the inlet gas is divided into two paths, one of which directly acts on the normally open main valve to open it, the solenoid valve normally opens the cavity B to supply air, and the other acts on the pilot valve flap and along the gas The passage enters the normally closed control chamber F to seal the normally closed main valve flap. When the electromagnet is energized, the pilot valve flap is closed, the gas in the normally closed control chamber F is discharged into the atmosphere from the air discharge port D, the normally closed control chamber F is released, the normally closed main valve flap is opened, and the solenoid valve normally closes the cavity C to supply air. At the same time, the gas will also enter the normally open control chamber E along the gas passage, and the normally open main valve flap is tightly sealed.


image


(a) Power-off state (b) Power-on state


1. Valve body 2. Normally open main valve 3. Diaphragm 4. Pilot valve 5. Electromagnet 6. Normally closed main valve


A-air inlet B-normally open cavity C-normally closed cavity D-discharge port E-normally open control cavity F-normally closed control cavity G-normally open control cavity venting port H-normally closed control cavity venting port