# Hollow shaft vs Solid shaft – Difference (Explained)

The key point that differentiates the Hollow shaft vs Solid shaft is that the cross-sectional area of the hollow shaft is spread away from the axis of rotation while the cross-sectional area of the solid shaft is spread closer from the axis of rotation.

## Solid and Hollow shaft:

As shown in below figure-A, the solid shaft doesn’t have any hole at the center while the hollow shaft has a through-hole at the center of the shaft cross-section.

The profiles of the circular solid shaft and hollow shafts are shown below.

As shown in the above figure, for the hollow shaft, the cross-sectional area is spread away from the axis of rotation. For the same weight per unit length, the hollow shaft has a high moment of inertia than the solid shaft. Therefore the hollow shafts are stiffer than the solid shafts for the torsional and bending load.

Thus for the same weight, the hollow shafts have higher torsional stiffness and bending stiffness than the solid shafts.

## Hollow shaft vs Solid shaft:

FAQs:

1. Why is a hollow shaft better than a solid shaft?

The hollow shafts are lighter and provide more stiffness than the solid shaft of the same weight, thus hollow shafts are better than the solid shafts.

2. Is a hollow shaft transfers more torque than a solid shaft?

For the hollow shaft and solid shaft of the same weight, the hollow shaft transfers more torque than the solid shaft.

Pratik is a Graduated Mechanical engineer. He enjoys sharing the engineering knowledge learned by him with people.