Both pressure relief valves (PRV) and pressure safety valves (PSV) are used for process safety to relieve excess pressure. Although they’re often used interchangeably, they do have different functions and it’s important to know the difference. Don’t miss out on new

In the most basic terms, the difference is that pressure control valves are the first line of defence and is therefore used for primary safety, 

Thermal relief valves are also known as thermal safety valves, temperature relief valves, or thermal expansion relief valves. It is a safety device employed in liquid piping and pipeline systems to protect the equipment and system. When the thermal expansion of a liquid creates excessive pressure inside a closed system, the thermal relief valve

A safety valve is a valve that acts as a fail-safe. An example of safety valve is a pressure relief valve (PRV), which automatically releases a substance 

That stated, relief valves and safety valves do function slightly differently: Relief Valves are made to control pressure inside a system, most frequently in fluid or compressed air systems. These valves open compared to the rise in system pressure. What this means is it normally won't fly completely open once the product is slightly overpressure.

The safety valve belongs to the pressure release device, which can only operate when the working pressure exceeds the allowable range to protect the system. The relief valve can make the high-pressure medium quickly to meet the pressure requirements of the system and its working process is continuous.

8/13 · Here's a list of common mistakes with boiler-safety-relief valve installations: Relief valve piping. In one application, the boiler contractor installed a bushing on the outlet of the safety relief valve. Instead of 1 1/2-in. pipe, the installer used 3/4-in. pipe.

A safety Relief Valve is a pressure Relief Valve characterized by rapid opening or pop action, or by opening in proportion to the increase in pressure over the 

2. The opening of a relief Valve is directly proportional to the increase in the vessel pressure. 2. A safety valve opens almost immediately and fully in order to prevent over pressure condition. 3.

1/14 · The basic difference in their operating principle: The safety valve relieves the pressure into the atmosphere i.e. out of the system, it can be a pressure relief device of fluid vessels, when the set pressure value reached then the valve opens almost fully. On the contrary, relief valve relieves the pressure by relieving the fluid back into the

Safety valve — This device is typically used for steam or vapor service. It operates automatically with a full-opening pop action and recloses when the pressure drops to a value consistent with the blowdown requirements prescribed by the applicable governing code or standard. • Relief valve — This device is used for liquid service.