The correct operation of the safety valve is crucial, then, in the installation, use and maintenance of the safety valve, what are the key matters needing our special attention?
First of all, the quality of safety valves is the basis for their stable and safe operation. However, if the user is not operating properly, it may lead to the safety valve can not work properly. According to user feedback, 80% of safety valve failures are caused by improper installation and use. Therefore, users need to deeply understand the relevant knowledge of the safety valve, and strictly follow the operating specifications.
Safety valve is a precision mechanical instrumentation, its installation and use of relatively high requirements. In the continuous production of industrial processes, after the completion of the device will usually go through the blowing, gas tightness test, pressure test and so on many links, and then finally put on trial. Here, a common mistake made by users is to install safety valves on the process piping during the blowdown phase. Since the safety valve is closed at this time, debris may enter its inlet during the blowdown process. During a pressure test, the safety valve may actuate, but when seated, it may fail due to the presence of debris.
According to national standards, one of the following measures should be taken during blowdown:
It is possible to install the safety valve on the process piping, but it must be sealed by adding a blind plate at the inlet of the safety valve.
Instead of installing the safety valve for the time being, use a blind plate to seal the connection between the safety valve and the process piping, and then reinstall the safety valve after the pressure test is completed.
Lock the safety valve. However, this method is risky because the operator may forget to remove the lock, resulting in the safety valve not functioning properly.
During use, process operations need to be kept smooth to avoid excessive pressure fluctuations causing the safety valve to trip. According to national standards, once a safety valve has tripped, it must be recalibrated.
In addition, the technical parameters provided by the user must be accurate and the application medium must be fixed. For example, if the medium provided in the technical parameters is air, but in the actual use of chlorine gas, chlorine and water vapor will form hydrochloric acid, which will cause corrosion of the safety valve. Or, if the technical parameters provided in the medium for water, but the actual medium contains sand and gravel, then it will cause wear and tear on the safety valve. Therefore, users should not change the process parameters at will. If they do need to change them, they must check whether the safety valves provided by the valve manufacturer are suitable for the changed conditions and communicate with the manufacturer in time.
If all the above steps can be operated correctly according to the standard specification, then the safety valve needs to be tested every year. At the same time, the operator needs to hold a “special equipment operator’s license”. This will ensure the continuous and stable operation of safety valves and provide safety for industrial production.
