The high-pressure safety valve is a safety protection valve, and its opening and closing parts are normally closed under the action of external force. It is divided according to the structural form, which is divided into plumb type, lever type, spring type and pilot type; according to the structure of the valve body, it can be divided into two types: closed type and non-closed type. The following are the items that should be paid attention to when installing the high-pressure safety valve: 1. For boilers with a rated evaporation capacity greater than 0.5t/h, at least two safety valves should be installed; for boilers with a rated evaporation capacity less than or equal to 0.5t/h, at least A safety valve; for boilers with a rated steam pressure less than or equal to 3.82MPa, the safety valve throat diameter should not be less than 25mm; for boilers with a rated steam pressure greater than 3.82MPa, the safety valve throat diameter should not be less than 20mm.