Segment ball is quarter turn control valve mainly recommended for throttle service, but it is also applicable for shut off service. Segment ball is in V-notch design with strong cutting force and self-cleanness, especially suitable for control of medium containing fibre and tiny solids. Therefore, it is widely used in the control systems in industries such as pulp and paper, petrochemistry, petroleum, chemical fibre, power, metallurgy, pharmacy, environtental protection etc.