Explain the meaning of an interference fit between a shaft and hole. - Leaving Cert Engineering - Question (e) - 2010

An interference fit occurs when the diameter of a shaft is larger than the diameter of the hole it is intended to fit into. This results in a tight assembly, where the shaft must be pressed into the hole.

Key Characteristics:

1. Tight Assembly: The interference fit ensures a secure connection between the two components, preventing any relative motion.
2. Force Application: Usually requires the application of significant force to assemble the components due to the snug fit.
3. Applications: Commonly used in machinery where precise alignment and strength are critical, such as in gears and pulleys.

Practical Implications:

• This type of fit is particularly valuable in applications demanding a robust connection that can withstand torque and stresses.
• Designers must carefully consider tolerances to ensure that the interference fit achieves the desired interference without damaging the components.