Product Number:21210511916
Product Name:QDQ421F Emergency Natural Gas Cut-off Valve
Spec:
Product Notes:
Product Category:Gas-specific valve
QDQ421F Emergency Gas Cut-off Valve - Product Description
The emergency shutdown valve for natural gas is a type of actuator valve in an automated system, composed of a multi-spring pneumatic diaphragm actuator or a floating piston actuator, along with a regulating valve. It receives signals from regulating instruments to control the cutting off, opening, or switching of fluids within process pipelines. It features a simple structure, sensitive response, and rapid action. It can be widely used in industrial production sectors such as oil, chemical, and metallurgy. The air source for the pneumatic cutoff valve requires filtered compressed air or nitrogen, and the medium flowing through the valve body should be liquid and gas free of impurities and particles.
The emergency shut-off valve boasts superior technical performance with low load loss and high reliability. Installed on liquefied gas, natural gas, and gas phase pipelines, it is used in conjunction with remote gas sources. It controls the opening and closing of the valve to utilize the gas source. This ensures rapid manual depressurization of the gas source in case of large-scale leaks or fires on the pipeline or tank. Additionally, at a high temperature of ≥75% p5C% D, the fusible alloy melts automatically, causing the cylinder to depressurize and the valve to close quickly to stop the leak, providing safety protection. It is widely used in safety facilities of gas supply network systems, gas thermal energy factory workshops, gas boiler rooms, and residential buildings.
QDQ421F Emergency Shutdown Valve for Natural Gas, Electric Control Working Principle
Install a two-way three-way solenoid valve at the gas source inlet of the emergency shutdown valve, controlled by a remote electrical control panel to switch the valve on and off.
2. The gas leak alarm activates, the solenoid valve is energized to exhaust, and the valve automatically closes.
3. Manually control the solenoid valve (press the red clip) to exhaust; the valve will automatically close.
4. Valve Installation Direction: High In, Low Out
QDQ421F Emergency Natural Gas Cut-off Valve Performance Specification
Pressure Rating: 1.6/4.0 MPa
Cylinder working pressure: ≤2.0 Mpa
Operating Temperature: -40~80℃
Cylinder Operating Medium: Nitrogen, Anhydrous Air
Medium of Use: Liquefied Gas
Melting Close Time: ±70℃
Shut-down time: ≤5 seconds
Cylinder Opening Pressure: ≥0.3-0.6 Mpa
Body: Cast steel, stainless steel. 304, 316, 316L
Spring: 50CrVA (spring steel)
Cylinder, piston: Ductile iron
Seal rings, O-rings: Nitrile rubber
Type: Normally Open, Normally Closed
































