The correct operation of the safety valve is very important, so what should be paid attention to in the installation, use and maintenance of the safety valve?
The quality of the safety valve itself is the premise to ensure safe and stable operation, but if the user does not operate properly, it may cause the safety valve to fail to operate normally, so installation and use are very important. Among the problems reported by users, safety valve failures caused by improper installation and use account for 80%. This requires users to improve their understanding of safety valve product knowledge and technology, and strictly follow the operating specifications.
The safety valve is a precision mechanical instrument, and its installation and use requirements are relatively high. For the continuous process industry, after a set of devices is built, it will go through several procedures such as purging, air tightness, and pressure testing, and then will be put into a trial run. A common mistake made by users is to install the safety valve on the process pipeline during purging. Since the safety valve is closed, during the purging process, debris enters the inlet of the safety valve. During the pressure test, the safety valve jumps and returns. Due to debris when seated, the safety valve will fail.
According to national standards, when purging, the following measures must be taken:
1. The safety valve is allowed to be installed on the process pipeline, but a blind plate should be added to the inlet of the safety valve for sealing.
2. Do not install the safety valve, use a blind plate to seal the connection between the safety valve and the process pipeline, and reinstall the safety valve after the pressure test.
3. The safety valve is locked, but there is a risk in this measure. The operator may forget to remove it due to the negligence of the operator, resulting in the safety valve not working properly.
In the process of use, the process operation must be stable. If the pressure fluctuation is relatively large, the safety valve will jump. According to the national standard, once the safety valve jumps, it must be re-calibrated.
In addition, the technical parameters provided by the user must be accurate, and the application medium must be fixed. For example, the medium in the technical parameters provided is air, but if chlorine gas is added during use, the chlorine gas will combine with water vapor to form hydrochloric acid, which will affect the safety valve. Cause corrosion; or the medium in the technical parameters provided is water, but the actual medium contains sand and gravel, then it will cause wear on the safety valve. Therefore, the user cannot change the process parameters at will. If it is necessary to change, it is necessary to check whether the safety valve provided by the valve manufacturer is suitable for changing the working conditions in the future, and communicate with the manufacturer in time.
If all of the above can be properly operated in accordance with the standard specifications, the safety valve must be tested every year, and the operator should obtain a “special equipment operator certificate”.