Review of Shrink Fit Shaft Vibration Analysis

A drive shaft is a mechanical device for transferring power from the engine or motor to the point where useful work is applied. Most engines or motors deliver power as torque through rotary motion. This is extracted from the linear motion of pistons in a reciprocating engine. From the point of delivery, the components of power transmission from the drive train. The drive shafts are carriers of torque which are subject to torsion and shear stress, which represents the difference between the input force and the load. Thus it needs to be strong enough to bear the stress, without imposing too great an additional inertia by virtue of the weight of the shaft. A shrink-fit is a semi-permanent assembly system that can resist the relative movement or transmit torque between two components through the creation of high radial pressures at the interface of its constituent parts. It provides a low cost joining method and is widely used in - industry, with applications to cutting tool holders, Wheels and bands for railway stock, turbine disks, rotors for electric motors and for locating ball and roller Bearings. Shrink-fits are also an effective way of assembling machine elements such as a gear to a shaft to Transmit torque. The underlying principle involves establishing a pressure between the inside diameter of the gear hub and the outside diameter of a shaft through interference in dimensions at their radial interface. Commonly, expansion of the external part by heating, or cooling of the shaft is employed, the part located and then the whole assembly returned to operating temperature whereupon the pressure maintains part location to allow transmission of a torque and vibrations. Initially, the friction moment is carried out at the contact surface of outer hollow shaft and inner solid shaft while solid shaft is inserted in hot hollow shaft (150-300 ℃) Resulting hole inside hollow shaft expanded and semi-permanent assembly between hollow and solid shaft formed. When this composite shaft assembly is cooled up to room temperature (27 ℃), the outer shaft gets compressed and it exerts pressure on the inner solid shaft. This can be calculated using Lame's equation [1]