Gas pressure regulators are devices used to reduce the pressure of a gas supply, and to maintain the pressure at lower, usable levels. They are made up of a loading mechanism for controlling the delivery pressure, a sensing mechanism and a control mechanism that reduces the pressure. The four main types of gas pressure regulators are line regulators, general purpose regulators, high purity regulators and special service regulators. Gas pressure regulators can be found in single stage or two-stage configurations.
Line gas pressure regulators are point-of-use regulators designed for use on low-pressure pipe lines, but may also be used as the second stage in a two-stage regulator configuration with a high-pressure cylinder regulator. They typically have their inlet and outlet opposite each other, with a single gauge that indicates the outlet (reduced) pressure.
General Purpose Regulators
General purpose gas pressure regulators are low-cost pressure regulators for long life in non-corrosive environments. They are typically made of brass with diaphragms made of neoprene or other elastomeric materials (materials with the elastic properties of natural rubber). Because some elastomeric diaphragms are permeable to oxygen they are not suitable for use in gas chromatography or other applications in which contamination can not be tolerated. General purpose gas pressure regulators are typically equipped with two gauges, indicating the inlet pressure and the delivery pressure.
High Purity Regulators
High purity gas pressure regulators are designed to keep contamination from the atmosphere to a minimum. Instead of neoprene or other elastomeric material, the diaphragms in these regulators are made of stainless steel or other corrosion-resistant metals.
Special Service Regulators
Special service gas pressure regulators are designed and constructed for specialized applications such as ultra-high-pressure processes or processes that use corrosive gases. An example of an ultra-high-pressure process is the sterilization of foods or pharmaceuticals. Many manufacturing processes use corrosive gases such as ammonia, hydrogen chloride, chlorine or methylamine. Some special service regulators are specifically designed for use with certain gases such as oxygen, acetylene and fluorine. Compressed oxygen and acetylene typically are used in welding applications; compressed fluorine is widely used in manufacturing and chemical laboratories.
Single Stage vs. Two-Stage Configurations
Any of the four main types of gas pressure regulators can be found in either single stage or two-stage configuration, depending on the application.
Single stage gas pressure regulators reduce the pressure from the source to the end-use equipment in one step. They are useful for short-duration uses and when the delivery pressure doesn't require precise control. Supply pressure variation makes precise control with a single stage regulator impractical. The pressure in a gas cylinder, for example, decreases as the cylinder empties.
A two-stage regulator reduces the pressure from the supply to an intermediate, constant level that is used as an input into a second pressure regulator. The constant input pressure into the second regulator makes precise control of the delivery pressure possible even when the supply pressure varies.
- Photo Credit pressure gauges image by laurent dambies from Fotolia.com gas mixing valve image by Steve Lovegrove from Fotolia.com
- What Is a Gas Regulator?
How to Size a Gas Regulator
Gas regulators control the overall amount of pressure in a combustible gas line. All gas appliances require low gas pressure for safe...
How to Tell the Differences in Propane Regulators
Propane regulators control gas flow and lower the pressure from the tank to the appliances in the gas system. They act as...
The Fisher Propane Regulator R232-BBF Specifications
A propane regulator manages the pressure inside your propane tank, which keeps the pressure from blowing out hoses or potentially causing an...
- What Nutrients Are in Seaweed?