SECTION A6.3 EXAMPLE1

A 1/2 HP motor operating at 1000 RPM rotates a 30 in long, 0.75 in diameter, 0.035 in thick aluminum alloy torque tube which drives the gear mechanism for operating a wing flap. Determine

- the maximum shear stress in the torque tube under full power and RPM,
- the angular deflection of the shaft at one end relative to the other.

EQUATIONS USED

SOLUTION

First, based on the maximum power and RPM the torque applied to the tube is

Note that this external torque is reacted by an internal torque of the same magnitude at every section along the length of the tube.

Based on the above value of torque the maximum shear stress in the tube is

The resulting angular deflection (angle of twist) is determined to be

To Section A6.3