Introduction
This guide focuses on selecting actuators for McCANNA ball valves, highlighting the need for valve automation due to rising labor costs and the demand for reliability, speed, productivity, and safety. Flowserve provides various automated valve packages assembled by factory or trained distributor personnel.

Actuator Sizing Procedure
Actuator sizing involves calculating the actuator sizing torque using the formula: Actuator sizing torque = Basic valve torque x service factor x control factor x design factor. An example calculation is provided for a 3" McCannaseal valve.

Factors Affecting Actuator Sizing

• Seat Materials: Materials such as TFE, RTFE, graphite, and metal influence valve torque.
• Service Conditions: Media conditions like slurry or dry gas affect torque requirements.
• Actuator Design: Options include electric, double-acting pneumatic, or spring-return pneumatic actuators.
• Type of Control: On-off versus throttling impacts torque needs.
• Failure Mode: The actuator's failure mode affects torque calculations.

Torque Tables
Detailed tables list basic sizing torques for various valve types and sizes under different pressure conditions, essential for selecting the appropriate actuator based on valve size, seat type, and line pressure.

Recommendations
For clean lubricating media, refer to torque charts on pages 4-10. For modulating services or non-lubricating media, use factor multipliers to adjust torque calculations. It is crucial to consider all factors affecting torque to ensure proper actuator selection.

Conclusion
Proper actuator selection requires understanding the minimum and maximum air supply pressure for pneumatic actuators and the desired cycle time and voltage for electric actuators. Comprehensive guidelines and tables are provided to assist in selecting the correct actuator for McCANNA ball valves.