The function of the screw air compressor safety valve is to prevent the medium pressure in the pipeline or device from exceeding the specified value, so as to achieve the purpose of safety protection. The safety valve is a safety protection valve. Its opening and closing parts are in a normally closed state under the action of external force. When the medium pressure in the equipment or pipeline increases and exceeds the specified value, it automatically opens and discharges the medium to the outside of the system to prevent the medium pressure in the pipeline or equipment from exceeding the specified value.
According to the provisions of the "Safety Technical Supervision Regulations for Safety Valves" on regular calibration of safety valves, under normal circumstances, it is inspected once a year.
The method of safety valve calibration is:
1. Offline calibration of the calibration bench
This calibration method is to directly install the safety valve on the corresponding calibration bench, open the safety valve with a gas medium, and observe the pressure gauge on the safety valve to confirm whether there is a large discrepancy between the pressure value when the valve is opened and the specified pressure value. However, this method is not suitable for some back pressure safety valves and safety valves for high and low temperature media, and cannot be accurately detected;
2. Online instrument verification
Online instrument verification is to open the safety valve through external force, and then detect the pressure acting on the safety valve spring when it is opened, and verify the safety valve by comparing the pressure. This method does not affect production and has no significant impact on the pressure of the system, but this method cannot detect the sealing of the safety valve;
3. Boosting jump method verification
This method allows the safety valve to work directly in the air compressor system, continuously pressurizes the safety valve until it opens, detects the pressure value when the safety valve pops open, and completes the verification. However, this detection method will have a certain impact on the sealing of the safety valve, and there is also a certain risk in operation.