DBB Ball Valves

• —Compact design with full-bore, piggable, low-flow-resistance performance
• —Inlet and outlet close independently for true block-and-bleed isolation
• —Fire-safe design
• —Anti-blowout stem allows maintenance in the pipeline
• —Self-relieving (single piston effect): the seat relieves body-cavity overpressure to the line on either side — fully bi-directional
• —DIB-1 (double piston effect): the seat stays in tight contact with the ball in both directions, fully isolating the body cavity from the line — suited to services where trapped media is subject to thermal expansion
• —DIB-2: one self-relieving seat paired with one double-piston seat, for a unidirectional valve with built-in cavity relief on one side

High-Pressure Pneumatic Shell Test

For all cast steel gate, globe, and check valves, as well as cast trunnion and floating ball valves, RANGER-FZV submerges the completed, uncoated valve in water and pressure tests the casting with nitrogen or compressed air. Pinholes or casting deficits invisible to a standard hydrotest are revealed as bubbles in the water — castings have failed this test after passing hydrotest.