While all regulators can reduce pressure in a gas system, high purity regulators conform to very exacting standards of pressure control. Below, we discuss some basis of comparison that can help you choose a regulator that best suits your needs. Of course, our Sales and Customer Service teams would be happy to answer any further questions you may have about regulator design and operation.
Single Stage vs. Dual Stage Regulators
Single stage regulators reduce pressure in a single step to deliver a pressure within a specific range. Regulators designed in this way will show a slight variation in delivery pressure as the cylinder pressure falls during use. For this reason, single stage regulators are best suited for applications where a constant outlet pressure is not critical, where an operator can monitor and readjust pressure, or where inlet pressure is constant.
Dual stage regulators perform the same function as single stage regulators. However, delivery pressure remains constant as cylinder pressure decreases, and greater accuracy in pressure control is maintained because the pressure reduction is performed in two steps. Dual stage regulators are recommended for applications requiring a constant outlet pressure over the life of a gas cylinder.
In the US, the Compressed Gas Association (CGA) has designated specific cylinder connections for each gas service and pressure rating. Refer to CGA publication V-1 for more information. Noble Gas Solutions provide regulators with CGA connections to fit cylinder needs. Please note that a CGA connection limits the temperature range of a regulator to the guidelines of the connection.
Helium Leak integrity is a measurement of how well a regulator prevents gases from leaking into or out of a regulator body. Helium is used as the test gas because it is chemically inert, it is easy to detect, and it is an extremely small molecule with the ability to pass through the smallest leak. The lower the Helium Leak specification, the better the regulator will be at preventing leaks into the atmosphere and at minimizing contamination from gases outside the body.
Materials of Construction
The materials of construction for a regulator should be selected based on the properties and purity of the gas being used. Noble Gas supplies regulators made from brass, aluminum, and 316L stainless steel. Brass is compatible with most of the non-reactive gases. A choice of forged body or barstock construction is available. Forged body regulators are economical; however, their internal surface finishes are relatively rough as compared to barstock body regulators. Barstock body regulators have all wetted surfaces machined to a smooth finish, which reduces the possibility of contamination. 316L stainless steel is highly corrosion resistant and is suitable for use with many of the highly corrosive gases in their anhydrous form. Aluminum is an economical lightweight alternative to stainless steel for many of the mildly corrosive gases.
Special Application Regulators
While a single or dual stage regulator of the appropriate material will suffice in most gas services, some applications require specially designed regulators. If you are unsure about your requirements, please contact Noble Gas Solutions for assistance. To learn more about specialty gases and equipment you can view the Purity Plus catalog here.
About the Author: Christian Card
Christian Card is Sales Manager at Noble Gas Solutions. He has over 10 years of experience supporting the Capital Regionâ€™s specialty gas market. Christian works primarily out of the corporate office in Albany, NY. When out in the field he focuses on complex applications requiring absolute precision and reliability. In 2019, Christian earned Noble Gas Solutions’ Spotlight of the Year award for his outstanding performance in sales, service, and sales training.