All About Safety Valves: Frequently Asked Questions
The safety valve operates on a simple but effective principle: it maintains a balance between the force exerted by the pressure inside the system and the force exerted by a spring or a weight mechanism.30 Nov 2023
The primary purpose of a safety valve is the protection of life, property and environment. A safety valve is designed to open and relieve excess pressure from vessels or equipment and to reclose and prevent the further release of fluid after normal conditions have been restored.
PRV: PRVs are adjustable and can be set to relieve pressure within a specific range, making them suitable for processes with varying pressure requirements. PSV: PSVs are typically set to open at a specific, non-adjustable pressure level, ensuring consistent safety margins.
There are two main types of safety valves. Spring loaded safety valves and pilot operated safety valves. Overpressure is the pressure increase above the set pressure necessary for the safety valve to achieve full lift and capacity. The overpressure is usually expressed as a percentage of the set pres- sure.
Among the primary devices utilized for preventing overpressure and potential catastrophic failures are safety valves. These valves are designed to release a controlled volume of fluid from within a system when a predetermined maximum pressure is reached, thereby reducing excess pressure in a safe manner.
The generic term is Pressure relief valve (PRV) or pressure safety valve (PSV).
Pressure relief and safety relief valves will leak if the valve isn’t fully closed. This is a common problem in industrial settings where environments are often dusty or dirty. If there is debris in the valve, it can obstruct the valve from fully closing, causing it to leak.
