Safety valves and pressure relief valves are an important measure in order to ensure safe operating pressures. Therefore, it is important that they are installed properly. In this article, we will provide you with the needed information.
As previously stated, it is important that your pressure safety or relief valve is installed correctly. If the installation is not performed with caution it can lead to leakage or pose safety problems. In order to correctly install a safety valve onto your system, the following points should be taken into account.
The valve seat can easily be damaged by dirt and debris that is present in the system. To prevent dirt and debris from passing through the valve the system must be flushed prior to installation. Additionally, the valve should be installed in places where dirt and debris cannot collect.
Figure 1: Correct safety valve and pressure relief valve inlet piping
It is recommended that the valve’s set pressure should at least be 10% higher than the operating pressure in order to avoid leaking. Safety valves are known to exhibit leaking when it approaches 80% to 90% of the valve’s set pressure.
Although it is recommended to test safety valves over time, this should be done about once a year. Testing too will often pose risks of dirt or other forms of contamination to get into the valve seat and lead to leaks.
Safety valves are a common safety measure within steam systems. It is important to install the valves such that no condensate can collect on the upstream side of the safety valve’s disc. This is commonly done by installing the valve above the steam pipe. If the safety valve is installed below the steam pipe, the condensate will fill up the connection to the valve. The condensate can damage the valve seat and influence the valve operation. Figure 1 shows the correct installation for steam systems.
Figure 2: Correct vs incorrect safety valve installation for steam systems