A high torque rotating actuator is disclosed. The high torque rotating actuator has a variable helix angle that allows the actuator to generate greater torque near the end of its travel when it is needed to close a valve or operate a choke. The high torque rotating actuator is designed for use with valves and chokes. In a second embodiment, a high torque rotating actuator is configured to give a shorter overall assembly. As in the preferred embodiment, a variable helix angle is used to generate greater torque near the end of its travel when it is needed to close a valve or operate a choke.