|Butterfly, ball and plug valves are all parts which work in a rotary motion. These valves typically have a rotation angle of 90° which is why they are defined in the industry either as “quarter-turn valves” equipped with “quarter- turn actuators” (if automated) in the industry. Valves requiring a different rotation angle, e.g. 3-way ball valves are automated with “part turn actuators” .
Definition of „part turn actuator“ according to EN ISO 5211“
A part-turn actuator is an actuator which transmits a torque to the valve for less than one full revolution.”