This ONIS D3B (Double Barrier, Bleed & Blind) is a combination of an
ONIS Line Blind and one or two ball valves. It offers many benefits such as:

  • Reduced flange to flange dimensionn as ball valve is part of the ONIS
  • Dead chamber is minimized, the product loss during operation is lower
  • ONIS D3B uses less spiralwound gaskets when installed
  • Mechanical safety interlock between the Line Blind and the valves prevents any operation of the Line Blind if the valves remain open
  • Drain ports are included


Like all our products, the D3B is available in special steels (carbon steel, stainless steel, Ni-Alloys, duplex, inconel,…) for a wide range of temperatures, pressures and mediums and also available in fire safe design with graphite gaskets.

Bodies and flanges: Carbon steel, Stainless steel…
Line Blind slide gate: stainless steel, Ni-alloys…
Manual lever or gear operator
Pneumatic, electrical or hydraulic actuator