The CeraValve type KST is a ball valve with ceramic lining for open / close function and control tasks to be used in excessively abrasive and corrosive media. It is to be preferably used if special requirements are placed on the stem sealing, on the housing materials (PVDF, titanium) or if there are very high or very low operating temperatures and high pressures. The basic principle is based on the floating ball design. The seats are rigid (fixed), the ball has a defined clearance and is pressed against the downstream seat by the differential pressure, sea-ling it. The ¼-turn movement of the ball between 0 and 90 ° releases an accurately defined opening cross-section. The geometric shape of the ball defines the function and control characteristics. This ball valve has a “three part body” design. Consequently, it can be adapted to existing pipelines and the flow and control characteristics can be optimised. These valves are available with manual lever or gear box, as well as with pneumatic, electric and hydraulic actuators. The actuator is mounted by means of a yoke and adapter arrangement. All customary actuators can be used as part-turn valve actuators. Special connections are possible.