Precautions for installation and maintenance of spring-loaded safety valves

One:  When installing, all kinds of safety valves must be installed vertically.
Two:  There should be no resistance at the outlet of the safety valve to avoid pressure.

Three: The safety valve should be specially tested before installation, and its official tightness should be checked.

Four: The safety valve in use should be checked regularly.

The safety valve installation should meet the following requirements:

(l) The cross-sectional area of ​​the connecting pipe between the safety valve and the boiler should not be less than the cross-sectional area of ​​the inlet of the safety valve. If several safety valves are installed together on a short pipe directly connected to the drum, the cross-sectional area of ​​the short pipe should not be 1.25 times the exhaust area of ​​all safety valves.

Safety valves must be installed at the outlet of the type economizer and steam superheater.

(2) The safety valve should be installed vertically at the highest position of the boiler and header. Between the safety valve and the drum or header, there shall be no outlet pipes and valves for taking steam.

(3) The lever-type safety valve must have a device to prevent the heavy hammer from moving by itself and a guide frame to limit the lever’s deviance. The spring-type safety valve must have a device to lift the handle and prevent the adjustment screw from being twisted casually.

(4) For boilers with rated steam pressure less than or equal to 3.82MPa, the safety valve throat diameter should not be less than 25mm: for boilers with rated steam pressure greater than 3.82MPa, the safety valve throat diameter should not be less than 20mm.

(5) Boilers with a rated evaporation capacity greater than 0.5t/h must be equipped with at least two safety valves: boilers with a rated evaporation capacity less than or equal to 0.5t/h must be equipped with at least one safety valve. Dividable

(6) The safety valve should generally be equipped with an exhaust pipe, which should lead directly to a safe place and have sufficient cross-sectional area to ensure smooth exhaust. The bottom of the safety valve exhaust pipe should be equipped with a cavity and a drain pipe connected to a safe place. Valves are not allowed on the exhaust pipe and the drain pipe.