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What is the importance of Helium Leak Integrity?
Helium Leak Integrity gives a measure of how well a regulator will prevent leakage both, outward and inward. A regulator with a leak integrity of 1x10-9 cc/sec. will protect the process gas better than a regulator with a leak integrity of 1x10-8 cc/sec.

Why is there a 30 psig gauge on a regulator with an outlet pressure range of 0-15 psig?
For safety and reading accuraracy the American National Standards Institute (ANSI) recommends that pressure gauges never be used to more than 75% of full scale. Due to the fact that gases are compressible, the gas industry has standardized, where practical, on using guages to approximately 50% of full scale. From an accuracy standpoint, the standard guages on a regulator are ± 3% - 2% - 3%. This means that the bottom and top third of the scale have a ±3% error. The middle third of the scale will have ± 2% error.

Is the relief valve on a regulator designed to protect down stream equipment?
NO! The purpose of a regulator relief valve is to protect the regulator. If you have pressure sensitive equipment down stream from the regulator, it is recommended that a separate relief valve be installed down stream of the the regulator.

How do I determine the proper CGA connection for my regulator?
The Compressed Gas Association (CGA) has developed a group of connections for the outlet valve on a cylinder, CGA V-1. The purpose of the standards is to avoid the possibility of installing a regulator on the wrong type of gas cylinder. Most of the gas suppliers in the United States adhere to these standards. However, there are a few gases and mixtures where there are differences between suppliers. Therefore, CONCOA can not make the recommendation as to which CGA connection to use. There are markings on the cylider valve indicating the proper connection for that valve. If you can not find any markings contact your gas supplier.

In other parts of the world, there are similar standards. In particular DIN 477 (Europe and parts of South America) and BS 341 (Great Britian). CONCOA stocks most of these connections in brass, chrome plated brass and 316 stainless steel.

Do I need a single or dual stage regulator?
Both single and dual stage regulators will control pressure very well depending on the application for which the regulator is used. A single stage regulator will provide a constant outlet pressure provided that there is a nearly constant inlet pressure. If there is a large decay in the inlet pressure, there will be a slight rise in the outlet pressure when a single stage regulator is used. This may be acceptible if you are able to periodically readjust the pressure. If you can not and your application requires a constant pressure over the life of the cylinder, a dual stage regulator is recommended. A dual stage regulator performs the pressure reduction in two steps, there by negating the effects of a decaying inlet pressure.

What is the purpose for a diaphragm valve on a regulator?
The purpose of any valve on the outlet of a regulator is to either control flow or turn the flow of gas on or off. The diaphragm valve is primarily used to turn the flow on or off. For precise flow control, a needle or other type of valve is necessary. Keep in mind that regulators control pressure and valves control flow.

Can I use a brass regulator for a mixture containing 200 ppm H2S balance Nitrogen?
NO. A stainless steel regulator is recommended. While this mixture or similar mixtures containing small quantities of corrosive gas, may not be terribly corrosive to the brass regulator, part of the corrosive component will react with the regulator body. This means that even though there maybe 200 ppm H2S in the cylinder, you will not get 200 ppm out of the regulator.

What is captured venting?

Captured venting is a safety feature built into a regulator bonnet so if the diaphragm fails any gas which enters the bonnet can be piped away to a safe location. This feature is recommended for regulators in toxic, corrosive, or in some cases, flammable gas service.

When is purging a regulator recommended?
There are three reasons to purge a regulator:
1.Safety - to remove toxic or poisonous gases from the regulator before disconnecting the regulator from the cylinder.
2. Corrosion Resistence - many of the corrosive gases are non-corrosive provided that they do not come in contact with moisture. If they come into contact with moisture they form the acid phase of the gas which is extremely corrosive to most materials, including 316 stainless steel.
3. Purity - the removal of the air from inside a regulator after a cylinder change out prevents the air, which has entered the system, from being sent down stream to the process or analyzer.

How do you determine the flow capacity of a regulator?

There are two ways to determine a regulator's flow capacity. The first method is by calculation using the regulators Cv (value found in the specifications for each regulator). These calculations can be very complex when dealing with gases because they are compressible. The second, more accurate method, is to refer to the flow curves in CONCOA's catalog. These curves plot outlet pressure vs. flow for each available pressure range. The individual curves are developed through individual tests and are very accurate.

If you can not find the question you are looking for, contact us directly and we will be happy to help!

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