External “Pop-Action” Supplementary Pressure Relief Valves for Small ASME Containers and DOT Cylinders 3127 and 3129 Series

Designed for use as a supplementary relief valve in small ASME containers above ground and underground. They can also be used as a primary or secondary relief device in DOT cylinders, or as hydrostatic relief valves.

All operating components of these relief valves are out of the container connection, so the valves must be protected against physical damage.


    • Generous flow channels for low pressure drop.
    • Heavy-duty construction for long service life.
    • Soft seat valves have synthetic rubber seat disc for positive seals.


Body Brass
Spring Stainless steel
Seat disc Resistant rubber