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LINE REGULATORS are single stage regulators that are used toprovide point-of-use pressure monitoring and control. For example, a lab may have gas cylinders located in a room on the first floor.The gas may be piped to instruments located in a lab on the second floor. In this case, it is difficult to monitor the gas pressure directly at the instruments, since the regulators are located on the cylinders on the first floor. Aline regulator may be installed near the instruments for convenience of monitoring the delivery pressure at the point of use. These regulators are installed directly into gas lines, and have a single delivery pressure gauge. SINGLE STAGE regulatorsperform the same function as the two stage regulator using a single step reduction of source to outlet pressure. For this reason, the outlet pressure cannot be as accurately controlled as the source pressure decays. We highly recommend single stage regulators only be used in circumstances where the operator can monitor and adjust the regulator as needed or where the regulator is supplied a nearly constant source pressure. DUAL STAGE regulatorsreduce the source pressure down to the desired delivery pressure in two steps. Each stage consists of a spring, diaphragm, and control valve. The first stage reduces the inlet pressure to about three times the maximum working pressure. The final pressure reduction occurs in the second stage. The advantage of a dualstage regulator is its ability to deliver a constant pressure, even with a decrease in inlet pressure. For example, as a cylinder of gas is depleted, the cylinder pressure drops. Under these conditions, single stage regulators exhibit a “decaying inlet characteristic”; wherethe delivery pressure increases as a result of the decrease in inlet pressure. In a dual stage regulator, the second stage compensates for this increase, providing a constant delivery pressureregardless of inlet pressureconditions. The dual stage regulator is recommended for applications where a continuous supply of gas is required; such as the gas supplied to analytical instruments whereconstant delivery pressureis critical.

Regulators

Regulators - 30801 Introduction

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Regulators

Basic Regulator Types Regulators are used in gas delivery systems to reduce the pressurefrom a high pressure source to a safe working pressure for use. A pressure regulator should always be used when positive control of the pressure in a gas stream is required. Apressure regulator is as much a safety device as it is an important tool. All Matheson regulators are cleaned for oxygen service except as noted. There are two basic types of pressure regulators: a single stage type and a dual stage type. The outward appearance of the two distinctly different types is somewhat similar and may be difficult todistinguish. Most pressure regulators are fitted with two gauges to monitor pressures (most line regulators only have one). Established convention in the United States and Canada has situated the high pressure gauge being connected internally to the inlet side of the regulator (the right side of the regulator when facing from the front). This gauge is used to monitor the source pressure. The low pressure gauge connected internally to the outlet side of the regulator is situated on the left side of the regulator when facing from the front. This gauge is used to monitor the outlet pressure (this is the gauge commonly installed on most regulators).On occasion, an outlet valve is affixed to the outlet port of theregulator. This valve is to be used to turn the flow of gas on or off for brief periods of time. It should never be used to throttle or control the flow of gas emitted from a regulator. This practice could cause serious damage to both the regulator and its operator. Flow should always be controlled by some other piece of equipment such as a rotameter or mass flowmeter.
Regulators

Gauges

Gauges areused to monitor the pressurewithin a gas delivery system. The basic component of a gauge is a hollow metal tube that expands and contracts a very exact amount under varying pressures. This tube is connected to the part of the gauge usually screwed into a regulator and is also connected to a series of gears. These gears are further connected to a needle, which is what the user can view at the front of the gauge.

Matheson Regulators

HIGH PURITY – These products are suitable for applications wheremaintaining the purity of a gas or mixture is the overriding concern. Generally,these products are best suited to applications involving gases that are greater than 99.995% purity level (for pure gases) or analyzed mixtures. These products are also highly recommended when dealing with more hazardous gases that are either corrosive, toxic or pyrophoric. Typically these products are used in analytical laboratory applications or special process situations. GENERAL PURPOSE – These products are suitable for applicationswherecost is an overriding factor.Generally, these products are best suited to applications involving gases that are less than 99.995% purity level (for pure gases) or unanalyzed mixtures. Also, these products should not be used when there is a concern of moisture, air or hydrocarbon contamination to the gases under control.

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