It is a multi-purpose rotary segmented valve with eccentric plug, combining the best features of lift and rotary control valves and featuring high capacity and cavitation resistance, as well as wide range and accuracy of control. The shut-off and control valves operation principle is based on an eccentrically rotating spherical plug contained in a free flow body design. The plug seating surface is joined by flexible arms to a hub which slides onto a rotating shaft. The plug is free to center itself along the axis of the shaft. A positive seal between plug and seat is achieved by elastic deformation of the plug arms. The chamfered seat ring is fixed in the valve body by a threaded retainer. The plug and shaft are rotated through an angle of 50° by a lever linked to a powerful spring-opposed rolling diaphragm actuator. This actuator is used in a standard design. It is possible to produce various types of actuators depending on the project requirements. This equipment can be applied within the wide range of operating temperature.