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Valbart designed the VB2 & VB3 Side-Entry Trunnion-Mounted Ball Valves to assure bi-directional sealing of the valve with two independent floating seats. The design of these seats minimizes the torque required to operate the valve without losing the sealing power. This power is assured by zero differential pressure to the valve's maximum rated pressure. In addition, these repairable valves are manufactured to seal off both seats at the same time and to allow bleeding of the entrapped cavity pressure (DBB) with the ball in the closed position. The DBB feature allows for verifying that the seats are properly sealing.   

Features

• Trunnion-mounted ball: Features a fixed ball and floating seat rings. Bearings absorb the side load generated by the pressure acting on the ball. 
• Independent ball and stem: The ball and stem are independent to minimize the effect of side thrust from pressure acting on the ball.
• Double block and bleed (DBB): Both seats hold their respective pressure independently of the body cavity pressure, which is ideal to verify that the seats are sealing. 
• Soft-seated valves: In valves designed for standard service, a resilient material is inserted into the metal seat holder to provide a soft-seating action in addition to the metal-to-metal seating between the ball and seat rings.
• Self-relieving seat rings- two seat rings assure bi-directional sealing of the valves.
• Anti-blowout stem maintained because the stem is retained by the stem cover. 

Optional features

• Emergency sealant injection stem seals and seat face
• Metal seated valves
• Double piston effect seats 
• Extended stem and fittings for below ground service
• Numerous types of body, trim, seal area overlay and seal materials available   

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