ABSTRACT
Control valves are essential components of any piping system. When we use the term valve, it is manually operated whereas a control valve is one with an actuator that automatically opens or closes the valve fully or partially to a position dictated by signals transmitted from the controlling instruments. Based on actuation, control valves can be mainly classified into quarter turn valves, multi-turn valves and check valves. Quarter turn valve allows only 90o rotation and it includes ball valves, butterfly valves spherical valves and plug valves. In this work a ball valve is used for characterization study. A multi-turn valve allows 360o rotation and it requires 4-5 turns to completely open or close the valve. Gate valves, globe valves and pinch valves are all multi-turn valves.
