When the pressure in a piece of equipment like pressure vessels or boilers continues to increase beyond a particular value, the buildup of excess pressure can cause a catastrophic failure to the machine. To keep this from happening, pressure relief valves are used to help predetermine set pressures, and this protects the equipment as it helps relieve excess pressure. Here are the different types of relief valves that protect equipment like boilers and pressure vessels from excess pressure:
A Bailey safety valve is a regulator, which acts like a fail safe that protects equipment from damaging or exploding. A safety valve is mainly installed in different pressure vessels like electric power boilers, chemical plants and gas storage tanks. This type of valve automatically activates when the inlet-side pressure of the valve rises to a preset pressure. This causes the valve disc to open and discharge the gas or steam.
Once the pressure decreases to a set value, the safety valve closes. Not only does this valve control pressure, it also discharges fluid by itself with no electrical power support.
A relief valve is a category of safety valve that is used to limit or control the pressure in equipment. Pressure buildup can cause equipment or instrument failure, process upset or even a fire. To relieve the pressure from the system effectively, the pressurized fluid is allowed to flow out using an auxiliary system.
The relief valve is designed to open at a set pressure, and this helps protect pressure vessels from exceeding their designed pressure limits.
A pressure-reducing valve provides steady pressure to the part of the equipment that operates at a lower pressure than the standard system pressure. The most significant advantage of having a reducing valve in a boiler or pressure vessel is that you can set it to any desired downstream pressure, as long as it is within its limits.
Once the pressure-reducing valve is set, the pressure is maintained regardless of the changes in the system load variations and supply pressure. Reducing valves come in different types, and they include the following:
Spring-loaded relief valves: This is a reliable and simple system that provides over-pressure protection using spring force to reduce the pressure.
Balanced piston valves: This type of pressure valve is used when overlaid pressure is adjustable.
All valves are designed to reduce built-up pressure in different vessels. Make sure the valve you choose fits the equipment.