Series 69 is an industry standard liquid relief valve used for pressure relief and by-pass.
Engineered and designed for heavy duty, industrial and commercial usages. A single piece bonnet to eliminate leakage while allowing for simple cleaning. Easy removable sealed hex-cap to adjust pressure.

Series 69

Series 69 Liquid Relief Valves are calibrated (set to pressure) based on a range of flow-rates (GPM) versus seat size and set pressure. Standard valve is set to pressure to achieve flow rate maximum and minimums within each set pressure range. See capacity chart for details.
Temperatures -60°F (-51°C) to 406°F (208°C), low reduced to -320°F (-196°C) with PTFE option, high increased to 425°F (218°C) with stainless option.

Liquid Relief Valve Model Choices:
Brass/bronze valve with stainless steel springs
Stainless steel body / disk and springs with bronze bonnet

Wide Range:
Series 69 is available with a wider adjustable range (as an option). Valves are set to the mid-level pressure (or as specified). Typical wide-range is 150 psig increments. Note: Flow rates are not showing.


Include liquid by-pass, regulation, continuous pressure relief and over-protection. Also used on pumping stations, tanks, hydraulics, fluid / piping lines, oil fields, gas lines where a Liquid or Water Relief Valve is needed.


  • Field adjustable by simple removal of the hex-cap
  • Metal to metal precision lapped seating
  • Back pressure tested
  • Ease of cleaning and maintenance with simple bonnet removal
  • Stainless steel springs
  • Single piece - 100% leak free bonnet
  • Cryogenic compatible


  • BSPT and BSPP connections
  • Female Inlet
  • Viton embedded o-ring at hex cap
  • Packed lift lever
  • Wide range (WR) adjustable (150 psig increments)
  • Stainless steel body and disc
  • Low Lead Configurations (for a potable Water Relief Valve)
  • PTFE Seating
  • Tamper proof wire seal
  • O2 Cleaning
  • Adjustable wheel handle

Series 55

Series 55 are small compact non-code (liquid) water relief valves with a maximum pressure of 200 psig.

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