MECHANICAL POWER TRANSMISSION MADE EASY
Why Flexible Shaft? - Selection Criteria

There are Four principle criteria;
    Direction of Rotation
    Flexibility required (radius of bends)
    Speed (rpm)
    Torque to be transmitted

Other considerations;
    Number of bends
    Duty cycle
    Torsional deflection required (or maximum allowable)
    Environment

Direction of Rotation
Direction of rotation is determined by viewing the shaft from behind the driving end towards the driven end. Rotation is either Clockwise (C), or Anti clockwise (A) or Bi directional (B). It is important to correctly identify the direction of rotation as uni directional shafts are manufactured to suit the selected direction.

Flexibility

Speed
When considering the speed of the shaft, use the maximum rotational speed (rpm) of the application when making a selection. For maximum life, where possible, select a shaft that will operate significantly above that of the application.

Torque
Use the following formula to estimate the running torque for your application. Consideration must also be given to the stall and start up torque. Use the lowest running speed to determine the torque.
Torque (Nm) = P(kW) x 9550
                             r.p.m.