STRAIGHT THROUGH DESIGN
SEVERE SERVICE CONTROL VALVE
Precise control throughout the entire stroke
Ball is a solid round ball (no opening) usually made of solid stellite.
Because of the Venturi flow shape, when cavitation occurs it is concentrated
in the center of the flow stream and gradually dissipates downstream.
Section View
Close Throttling
Intermediate Throttling
Full Open
Control Valves Overview
The presence of a pressure differential at full open, and during all positions of the cage and ball, prevents suspended particles in the stream from settling out in the body, thereby keeping the valve clean and free of any material deposits. Also, in the full open position, any suspended particles flowing through this Venturi configuration tend to concentrate in the center of the diverging cone and through the orifice. This obviously helps in lessening the erosive action of the fluid on the valve surfaces, in particular the seat face. There is a slight rotation of the ball during the initial opening travel resulting in a new seating surface contacting the seat each time the valve is closed. Due to the freedom of movement of the ball in the conical seating surface, temperature changes will not affect a tight shut-off.