But might fail due to fatigue due to stress concentration in the root of the flanks. They can transmit higher torque compared to involute splines and serrations because of their large tooth thickness from minor to the major diameter of the profile. These have straight and parallel tooth flanks a shown in the figure below and as per various standards number of teeth can vary from 4 to 12.

Fixed spline as the name suggests is a joint that does not move axially such as gears, pullers, turbine wheels etc.įlexible splines slide axially, mainly used between shafts couplings and do not carry much torque as fixed spline joints.Īdvertisement Parallel-sided or Straight-sided spline

Splines and serrations can also be grouped as fixed spline or flexible spline depending on their relative axial movement.

Parallel-sided or straight-sided spline.

The term “spline” provides an umbrella term for all profiles and the splines can be divided into the following three groups based on their flank form. Surface wear, fretting corrosion, tooth breakage and fatigue failure are the most common failure modes associated with spline joints. Good spline joint provides very high secure torque transmission, little clearance, minimum backlash, good centring between the coupled components, low noise, low wear and small or no axial forces.

Relative axial movement of the mechanical transmission element is required for functional purposes such as speed reducers and clutches.

Mechanical transmission elements such as gears and pulleys might need removing from the shaft due to design for manufacture and assembly (DFMA) ie during assembly or to aid manufacturing.

They are used mainly for the following reasons.

Advertisement Application of splines and serrationsĪlthough they look like gears, Splines are only used to transmit torque and rotation on the same axis.

Sae 6b spline