Liquefied gas emergency shut-off valve QDQ421F

Product Name:Liquefied gas explosion-proof pneumatic emergency shut-off valve
Product Accessories: Explosion proof Pneumatic Triplet (Explosion proof Two Position Three way Electromagnetic, Explosion proof Signal Execution Switch, Air Filter Pressure Reducing Valve)
Product model: QDQ421F-16/25/40C
Product specifications: DN15-DN300
Pressure rating: 1.6Mpa-2.5Mpa-4.0Mpa
Applicable media: liquid ammonia, ammonia, natural gas, liquefied gas
Operating temperature:- 40~+80℃
Valve body material: cast steel, stainless steel 304, 316, 304L, 316L

Liquefied gas explosion-proof pneumatic emergency shut-off valveIt is a safety protection valve installed on liquid ammonia, ammonia, liquefied petroleum gas (gas), liquid and gas pipelines, used in conjunction with remote gas sources. The valve is controlled to open and close by the gas source, so that in the event of a large amount of leakage or even fire on the pipeline or storage tank, the gas source can be quickly manually depressurized, or when the high temperature is ≥ 75 ℃, the melting alloy will melt, and the cylinder will automatically depressurize. The valve will quickly close to prevent leakage, providing safety protection. Widely used in chemical hazardous material pipelines, gas supply pipeline systems, gas thermal energy factory workshops, gas boiler rooms, and residential safety facilities.

Explosion proof pneumatic emergency shut-off valve combines the advantages of globe valve, check valve, solenoid valve and pneumatic valve, with excellent technical performance, low load loss and high reliability. It is used to output a signal to the solenoid valve through a leakage alarm in case of emergency. The solenoid valve is powered on to shut off the gas source, and the valve automatically closes. It can also quickly control the opening and closing of valves on pipelines or storage tanks from a distance, ensuring personal and property safety.

Explosion proof pneumatic emergency shut-off valve is a type of valve in automation systems, consisting of a spring pneumatic diaphragm actuator or a floating piston actuator and a regulating valve. It receives signals from the regulating instrument and controls the cutting, connection, or switching of fluids in the process pipeline. It has the characteristics of simple structure, sensitive response, and reliable action. It can be widely applied in industrial production sectors such as petroleum, chemical, and metallurgical industries. The air source for the explosion-proof pneumatic emergency shut-off valve requires filtered compressed air, and the medium flowing through the valve body should be a gas free of impurities and particles.

Cylinder working pressure: ≤ 2.0Mpa
Cylinder medium: nitrogen, anhydrous air
Cylinder opening pressure: ≥ 0.5-0.7Mpa
Cylinder operating temperature: ≤ 75℃
Melting temperature of (fusible alloy): 75 ± 5 ℃
Cut off time: Valve diameter less than or equal to DN65, closing time ≤ 5 seconds
Valve diameter greater than DN65, closing time ≤ 10 seconds

Cylinder and piston: ductile iron
Spring material: 50CrVA (spring steel)
Sealing ring, O-ring: polytetrafluoroethylene, nitrile rubber
Opening type: normally open, normally closed

Install a two position three-way solenoid valve at the inlet of the emergency shut-off valve air source, and control the valve switch using a remote electrical control console.
1. The valve is in a normally open state during daily operation, and the solenoid valve coil is in a power-off state, without consuming electrical energy. Emergency situation occurs
When the gas leak alarm is triggered, the alarm output signal is sent to the solenoid valve. The solenoid valve is powered on for exhaust, and the valve automatically closes
2. Manually control the solenoid valve (press the red clip) to exhaust, and the valve will automatically close
3. After the staff have dealt with the accident, the valve will be manually reopened to restore gas supply.
4. Electrical protection level: CEI IP65/IP67
5. Explosion proof grade: Eexm Ⅱ T4/Eexm Ⅱ T5
6. Working voltage and power: AC 24V or 220V, 50Hz/14V; DC AC12V/8.5W, AC24V/8.5W

1. When storing, seal all external passages of this valve with plugs or cover plates and store it in a dry and ventilated room. Regular inspections should be conducted for long-term storage,
Eliminate dirt and apply rust proof oil on the machined surface to prevent rusting.
2. Valves can be installed on horizontal or vertical pipelines for use. Before installation, remove the dust cover and clean the inside of the valve to prevent dirt from entering
Damaged sealing ring inside the valve body.
3. The emergency shut-off valve adopts the principle of check valve, which can only cut off in one direction. The flow direction of the working medium of the valve is high in and low out. It must be noted during installation
The valve symbol indicates that the end to be protected serves as the valve inlet.
4. After the valve is opened for 12-14 hours every day, the valve disc should be promptly closed when the system is not working to avoid long-term compression of the spring and reduce the length of the valve
Reliability of long-term use.
5. When ordering products, the flange sealing surface form, pressure rating, and connection standard must be specified.

The above is the product information of explosion-proof pneumatic emergency shut-off valve. If you have any questions about the specifications, models, pictures, and technical parameters of explosion-proof pneumatic emergency shut-off valve, please contact us for detailed information.