Under the misalignment condition of two shafts of the equipments, the teeth contact in case of straight cut hub will be as minimum as shown in the figure No.1
Under heavy loads the ends of the hub teeth will get damaged resulting in the excessive play between hub & sleeve. And, therefore the reduction in life of coupling.
Triple-Crowned Teeth
The triple crowned teeth hub is manufactured on a fully automatic hobbing machine with built in crowning attachment which is controlled by hydraulic & electronic system.
Under the misalignment condition of two shafts on the equipment, due to the curvature on teeth flank the contact area is much more and therefore , there is increase in life of coupling.