Kunkle Stainless Steel Sentinel Steam Relief Valve Models 40R, 40RL

This non-code steam relief valve is made from durable stainless steel. Used as an audible warning (sentinel) valve on steam equipment, this valve is not meant for pressure relief. Used on steam turbines, these valves springs are made with high temperature alloy steel for stability at super heated temperatures.

Model Descriptions:

Non-code Steam Service, Sentinel Relief Valves

  • Model 40R: ½” or ¾” male NPT inlet with top discharge to give visible warning of system overpressure. Overall height: 5 ¼”. Weight: 1#.
  • Model 40RL: Same as 40R with plain left lever. Overall height: 6 ½”. Weight: 1 ¼#.


  • All parts are stainless steel (SS).
  • Precision-lapped beveled seats for optimum performance.
  • Pivot between spring and disc corrects misalignment and compensates for spring side thrust.
  • Each Kunkle valve is tested and inspected for pressure setting and leakage.


  • Sentinel (warning) on steam equipment. Intended as audible warning device, not for pressure relief.
  • Steam turbines.

Pressure and Temperature Limits:

  • 1 to 400 PSIG
  • -60° to 850°F

Please refer to the Kunkle Model 40R and 40RL Catalog or Contact Us for additional information.

Request A Quote