Double block and bleed valves operate on the principle that isolation can be achieved from both the upstream and downstream process flow / pressures. This is achieved by two ball, gate, globe, needle, etc. valves placed back to back, with a third "isolatable" valve in the centre cavity. Once isolation has been achieved in one or more of the main process isolation valves, the cavity that is created between these isolations can be drained. This is useful for flow diverting, sampling or injection situations, and for maintenance / integrity check situations where seat leakage can be monitored through the third "bleed" valve.

• Multiple Configurations with Ball, Gate, Globe, Needle Options
• Full or Reduced Bore
• Manual Lever, Gear or Actuator Operated
• Special Seat Design Options - Self Relieving / Double Piston Effect
• Operating temperature and fluids suitability - further information on request
• Firesafe / Cryogenic / Gas Service certified options
• Modification service available for all stock options

• ANSI 800, 1500 & 2500lb - Threaded, Socket Weld and Butt-Weld ends
• ANSI 150, 300, 600, 800, 1500 & 2500lb - Flanged RF, RTJ, Butt-Weld and Hub ends
• PN, API and other Pressure Class Valves available on request