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* A floating ball valve is one where the ball is not held in place by a trunnion. In normal operation, this will cause the ball to float downstream slightly. This causes the seating mechanism to compress under the ball pressing against it. Furthermore, in some types, in the event of some force causing the seat mechanism to dissipate , the ball will float all the way to metal body which is designed to seal against the ball providing a somewhat failsafe design. | * A floating ball valve is one where the ball is not held in place by a trunnion. In normal operation, this will cause the ball to float downstream slightly. This causes the seating mechanism to compress under the ball pressing against it. Furthermore, in some types, in the event of some force causing the seat mechanism to dissipate , the ball will float all the way to metal body which is designed to seal against the ball providing a somewhat failsafe design. | ||
Manually operated ball valves can be closed quickly and thus there is a danger of water hammer. Some ball valves are equipped with [[Actuators]] that may be pneumatically or motor operated. These [[Valves]]can be used either for on or off or flow control. A pneumatic flow control valve is also equipped with a positioner which transforms the control signal into actuator position and valve opening accordingly. | Manually operated ball valves can be closed quickly and thus there is a danger of water hammer. Some ball valves are equipped with [[Actuators]] that may be pneumatically or motor operated. These [[Valves]] can be used either for on or off or flow control. A pneumatic flow control valve is also equipped with a positioner which transforms the control signal into actuator position and valve opening accordingly. | ||
==Sources== | ==Sources== | ||
[http://en.wikipedia.org/wiki/Ball_valve Wikipedia Ball valve] | [http://en.wikipedia.org/wiki/Ball_valve Wikipedia Ball valve] |