Delval Flow Controls offer a wide range of Delval Trunnion Mounted Ball Valves. All Delval Ball Valves are manufactured and tested in conformance with API 6D specifications and designed to meet our customers’ demanding service conditions.
In Trunnion Mounted Ball Valves, the ball is held in a fixed, axial position by upper and lower trunnions and can move only in a rotational mode. The seats are contained in metal carriers that are spring loaded against the ball. Line pressure applied to a closed valve increases the spring loaded upstream seat to effect a tight seal. The primary seating is therefore on the upstream seat, permitting trunnion mounted ball valves to be used for “block and bleed” services.
- Spring loaded floating seats maintain contact with the ball and provide a tight shut off even at low pressure differential. Independent sealing of upstream and downstream sides facilitate draining of fluid from body cavity, and thus double block and bleed operation.
The anti-blowout stem permits the replacement of the stem seals with the vale in the fully closed or open position. As the stem motions from full open to full close, there is a 90 degree rotation, and ball valves are ideally suited for automatic operation.
All Delval stems feature anti-static grounding device as standard. These devices ensure electrical continuity between valve ball, stem and body, thus eleminating the possibility of static electrical charges creating sparks within the valve.