This European Standard specifies requirements for the attachment of part-turn actuators, with or without gearboxes, to industrial valves.The attachment of part-turn actuators to control valves is in accordance with the requirements of this standard only when subject to an agreement between the supplier and the purchaser.This standard specifies :flange dimensions necessary for the attachment of part-turn actuators to industrial valves (see Figure 1a) or to intermediate supports (see Figure 1b);driving component dimensions of part-turn actuators necessary to attach them to the driven components;reference values for torques for interfaces and for couplings having the dimensions specified in this standard.The attachment of the intermediate support to the valve is not the subject of this standard.