In compliance with ISO 5210, a multi-turn actuator is capable of withstanding thrust applied to the valve and transmits torque to the valve for at least one revolution. In general, multi-turn actuators are required to perform more than one revolution. Consequently, gate valves are often equipped with rising valve stems. They are operated on the basis of several revolutions performed by the multi-turn actuator. Therefore, the multi-turn actuator is equipped with a hollow shaft housing the gate valve stem for these applications.
Slide/Sluice Gates. For example any Fontaine actuated gate
Knife Gate and Traditional wedge and double disk gate valves
Any valve that requires more than 90deg of travel. Often due to torque/rimpull customer requirements.