121-8203 - Miller Smith Silverline 2-Stage Regulator CGA 326 0-60 PSI

Technical Overview of the Miller Smith 121-82-03

The Miller Smith 121-82-03 is a precision-engineered device from the Silverline 120 Series, designed to meet the rigorous demands of laboratory, general plant, and maintenance shop environments. As a general-purpose two-stage regulator, it excels in applications requiring unwavering delivery pressure despite fluctuations in cylinder pressure. This model is specifically configured with a CGA 326 inlet connection and provides a delivery pressure range of 0-60 PSIG, making it suitable for applications requiring fine low-pressure control.

Construction and Durability

Engineered for longevity and reliability, the 121-82-03 features a rugged brass construction machined from bar stock. To enhance its resistance to environmental factors and maintain a clean aesthetic suitable for laboratory settings, the body, bonnet, and gauges are fully plated. This plating offers superior protection against oxidation and minor corrosive elements found in industrial atmospheres. The internal mechanism includes a filtered seat design, which is critical for maintaining gas stream purity and preventing particulate damage to the seating surface, thereby extending the service life of the regulator.

Performance Specifications

The core performance advantage of this unit lies in its two-stage regulation capability. By reducing pressure in two steps, the regulator compensates for the drop in cylinder pressure as gas is consumed, ensuring the outlet pressure remains constant without manual adjustment. Control is managed via a large 1-7/8 inch diaphragm, which provides exceptional sensitivity and response to pressure changes. The unit is rated for a maximum inlet pressure of 3500 PSIG and includes a preset safety relief valve that vents to the atmosphere, ensuring safe operation with non-hazardous gases. The outlet is equipped with a standard 9/16-18 RH connection, and the unit features large 2-1/2 inch single-scale gauges for precise monitoring.

Gas Compatibility

While the CGA 326 fitting is specific, the manufacturer designates this regulator for use with inert and non-corrosive gases such as Air, Nitrogen, CO2, and Argon. Users must ensure their cylinder connections match the CGA 326 standard or utilize appropriate adapters where safe and applicable. This regulator is not recommended for applications where inboard diffusion of air or outgassing of elastomeric components could compromise the work, nor is it suitable for hazardous gas service.