A pressure regulator is a useful valve for controlling the flow rate of a gas or liquid. The valves automatically cut off the flow of the gas or liquid when the pressure inside the tank reaches a predetermined point. Usually, a pressure regulator is used to prevent high-pressure fluid or gas supplies from exploding, or to regulate the safe pressure range for less volatile materials.
Pressure regulators vary depending on whether they are regulating the pressure of a gas or liquid. Pressure regulators are not interchangeable with flow regulators. For pressure regulation in gasses and liquids, flowmeters, mass flow controllers, and rotometers are used. In some cases, it may be necessary to have a flow rate regulator and a pressure regulator in the same line.
Since many industrial and commercial processes use high-pressure processes, there is actually a large demand for pressure regulators of various kinds. The main industries that use pressure regulators include:
- Propane and gas tanks
- Oil and petroleum processing and refining plants
- Gas and power companies
- Mining equipment
- Oxygen-fueled welding and metal processing
- Water pressure reduction
- Air compressors
Pressure regulators come in two unique varieties- the single stage and the double stage regulator. The single stage regulator allows high pressure gas or liquid in when the valve is opened. The interior pressure rises as the valve fills with the liquid or gas. When the pressure reaches the predetermined pressure rating, the valve automatically closes. This form of regulator can be adjusted by hand to allow different pressures through.
The double stage regulator works just like the single stage, but it uses two separate valves and regulators instead. This allows the pressure rating to change gradually, and to maintain a more consistent level.