Featured Valve: Kunkle Series 900

Bronze, steel and stainless steel safety relief valves for air, gas, steam, liquid and vacuum service that meet ASME Section VIII, ‘UV’; Section I, ‘V’, are National Board certified and PED certified for non-hazardous gas. Of course, we have them in stock.

Kunkle Series 900 valves are suitable for air/gas compressors, liquid filled pressure vessels/systems, high temperature/pressure hot water boilers, for pressure vessels containing air, gas or steam and process and industrial applications requiring steel/stainless steel construction, as well as for vacuum service. Featured Valve: Kunkle Series 900


  • Heavy duty cast valve bodies
  • Seats lapped to optical flatness
  • Available with resilient soft seats for superior leak-free performance
  • Standard SS spring for temperatures to 550°F (288°C) and optional alloy spring to 800°F (427°C)
  • Threaded cap standard (back pressure tight) and maximum back pressure 50 psig [3.4 barg]
  • Hex on valve nozzle provides for easy installation
  • Warn ring offers easy adjustability
  • Pivoting disc design offers exceptional seat alignment
  • Guide to nozzle ratio reduces friction
  • Full nozzle design for optimum flow performance
  • Threaded side outlet for piped off discharge to eliminate fugitive emissions
  • Each valve tested and inspected for pressure setting and leakage

Did you know Erastus B. Kunkle invented the safety valve to prevent overpressure in locomotive engines? Kunkle patented it in 1875. Since that time, Kunkle has earned its reputation for high-quality valves, and other equipment manufacturers ship their products with Kunkle’s valves pre-installed.

NASVI has stocked Kunkle safety relief valves since the 1990’s, so we are confident when we call ourselves Kunkle safety valve experts.