What Are Pressure Relief Valves and How to Properly Install Them?

As the name indicates, a pressure relief valve provides relief or protection against overpressure in a pressurized system. When the pressure in a vessel or system goes beyond its limits or exceeds the maximum allowable working pressure, it is known as an overpressure event. This is where the pressure relief valve comes into play, like the 3 bar pressure relief valve. Electronic pneumatic and hydraulic systems control fluid system variables such as pressure, temperature, and flow. These systems require a source to draw their power to operate like electricity or compressed air. A pressure relief valve is expected to perform its function typically even when power control failures in systems when they become uncontrollable. The process fluid is thus considered the only source of power for the pressure relief valve. 

Installation of Pressure Relief Valves

Proper installation of pressure relief valves is critical in ensuring safe operating pressures. If they are not installed correctly, it can lead to some dangerous outcomes.


The following steps should ensure that the 3-bar pressure relief valve is installed correctly. If not installed correctly, it can lead to leakages and post safety problems. 

Remove Dirt and Debris

When a lot of dirt and debris go into the system, it can cause damage to the seat of the valve. Therefore you must flush the system to remove any dirt and debris, preventing them from getting into the valve-like 3-bar pressure relief valve Screwfix before installation. Additionally, you should make sure not to install the valve in a place where any dirt and debris can be collected. Hence taking precautions is better than later on dealing with the consequences. 


  • Firstly, you need to mount the safety valves in a vertical position because they perform effectively upright. Whereas installing it in a horizontal positional can lead to problems and improper functioning. 
  • All the bolts need to be tightened relatively and equally when using flanged versions. If they are not pulled equally, that can affect the tightening of other bolts. Valves made from cast iron may even crack due to the uneven pressure loads exerted.
  • Tightening it to enough is essential but preventing over-tightening of the valve is even more critical. Both inlet and outlet threads can be damaged due to too much pressure, leading to leakages.
  • To prevent contamination of your system, apply a sealant to the male thread and not to the female line. Support is required if the valve is too tall, as much as 10 feet above a vessel. If there is no support, the valves and other parts of the systems will be damaged due to the reaction forces in a 3-bar pressure relief valve Toolstation. 

Inlet Piping

  • The inlet piping system must be short and direct. The diameter of the inlet piping should always be more significant than or equal to the valve inlet diameter, like a 3-bar pressure relief valve 15mm. This will compress the flow. 
  • Ensure that the inlet is not installed in a vessel near areas with high turbulence.
  • Ensure that the process lines are not connected to the relief valve inlet piping.
  • Ensure that you install the valve with a diameter of at least 8 to 10 compared to the Y bending fittings.

Valve Operation

For the valves like 3-bar pressure relief valves to properly operate, their set pressure must be at least 10% higher than operating pressure to ensure any leakages do not occur. When the valve pressure approaches 80% or 90%, it will relieve valve leakages.


If you do not have much time to test out the valves more frequently, at least make sure to test them once a year. Sometimes testing often poses risks of dirt and debris getting into the system and leading to leakages. 

Installation for Steam Systems

In steam systems, relief valves are commonly used for safety purposes. It is essential to avoid collecting condensate on the upright part of the valve’s disc by installing them correctly. This can be achieved by installing the valve above the steam pipe. But if you install it below the line, this can lead to the collection of 3-bar pressure relief valve compression in connection to the valve. This can cause enormous damage to the valve seat and its operations.