What is a Torsional & Axial Deflection?
Screw torsional deflection (sometimes called “windup”) may occur when loads are high (resulting in high drive torques) and when the screw is long.
Also, screw axial deflection caused by high compression or tension loads may be significant when loads are high and the screw is slender.
When rotation is used for feedback on a drive system, the engineer needs to be aware of these phenomenons. When the load is not where it is supposed to be, based theoretically upon the screws rotational position, screw deflections must be evaluated.
For more detailed information and a listing of the governing equations for torsional and axial deflection, see Roton Engineering Bulletin No. 974.