Q：How does the steam boiler safety valve work and what does it do?

A：The safety valve is an important safety accessory in the boiler. Its function is: when the pressure in the steam boiler is greater than the specified value (i.e. the take-off pressure of the safety valve), the safety valve will automatically open the valve to discharge the steam for pressure relief; when the pressure in the boiler drops to the required pressure value (i.e. ), the safety valve is automatically closed, so that the boiler can be used safely for a period of time under normal working pressure. For a long time, avoid the explosion caused by the overpressure of the boiler.
The purpose of installing and modifying the safety valve in the boiler is to release the pressure and remind the boiler when the boiler is overpressured due to factors such as vaporization, so as to achieve the purpose of safe use. Some boilers are not equipped with an air valve. When water enters the cold furnace to raise the fire, the safety valve is still removing the air in the furnace body; it flows away.

The safety valve consists of a valve seat, a valve core and a booster device. The passage in the safety valve communicates with the steam space of the boiler, and the valve core is pressed tightly on the valve seat by the pressing force formed by the pressurizing device. When the pressing force that the valve core can withstand is greater than the thrust of the steam on the valve core, the valve core sticks to the valve seat, and the safety valve is in a closed state; when the steam pressure in the boiler rises, the force of the steam acting on the valve core Increase, when its force is greater than the compression force that the valve core can withstand, the valve core will lift off the valve seat, the safety valve will open, and the boiler will depressurize immediately.
Due to the discharge of steam in the boiler, the steam pressure in the boiler is reduced, and the thrust of the steam that the valve core can bear is reduced, which is less than the compression force that the valve core can bear, and the safety valve is automatically closed.
Boilers with rated evaporation greater than 0.5t/h or rated thermal power greater than or equal to 350kW shall be equipped with two safety valves; boilers with rated evaporation less than 0.5t/h or rated thermal power less than 350kW shall be equipped with at least one safety valve . Valves and safety valves should be calibrated regularly and should be sealed after calibration.