MATERIALS OF CONSTRUCTION AND COMPATIBILITY
Mechanical designs are becoming smaller, more compact, and lighter in weight. Beswick Engineering is the leader and innovator in miniature pressure regulator technology. If your high technology application requires a high performance pressure regulator in a miniature package, please contact one of the mechanical engineers in our applications engineering department to discuss your requirements. A wide range of materials are available to handle various fluids and operating environments. Common regulator component materials include brass, plastic, aluminum, and various grades of stainless steel. Springs used inside the regulator are typically made of music wire (carbon steel) or stainless steel. Before selecting a regulator material, chemical compatibility between the fluid that will be passing through the regulator and the wetted materials within it must be considered. External environmental conditions should also be considered. For example, if the pressure regulator will be used on a ship at sea, then salt in the water and air may corrode the regulator if the proper materials are not selected. Even if a media is not particularly corrosive, it may still require special consideration. High pressure compressed CO2 for example, requires careful selection of seal materials, due to the possibility of explosive decompression and evaporative cooling as the media transitions from liquid to gas. Trace oils within gas cylinders or compressors may also become miscible with liquid CO2. These oils can then be deposited within the regulator when the CO2 evaporates. Seal compatibility with these oils must also be considered when selecting a regulator. Applications involving pure oxygen or breathing gas service require special attention to the cleanliness of the products selected, as well as a review of the lubricants/greases used in the assembly. Special lubricants may be required inside the regulator in order to reduce flammability and outgassing potential. When in doubt, it is always best to contact the manufacturer and discuss compatibility concerns. If the fluid coming into the regulator could contain debris, it is good practice to install a filter to protect the regulator. Some regulators come with integrated filter elements, while others would require a separate filter installed in front of the regulator. Without a filter, particulate matter could become lodged in the valve seat or damage the seals, preventing the regulating valve from fully closing. This would lead to a slow increase, or upward “creep” in outlet pressure over time.