Übermaßpassungen

Übermaßpassungen, also known as interference fits or press fits, are a type of mechanical fit where two cylindrical components are assembled with a slight overlap in their dimensions. The outer component, or housing, has a slightly smaller internal diameter than the inner component, or shaft, or vice versa. This difference in size, known as the interference, is carefully calculated to ensure a secure connection when the parts are assembled.

Assembly of an Übermaßpassung is typically achieved through force. The interference creates a condition where the outer part is stretched and the inner part is compressed during insertion. Once assembled, the inherent stresses within the materials hold the components together without the need for additional fasteners like screws or rivets. The tightness of the fit is crucial; too little interference will result in a loose connection, while too much can cause damage to the components during assembly or lead to excessive stress.

Heating the outer component or cooling the inner component can facilitate assembly by temporarily increasing the size difference. Once the temperature equalizes, the interference fit is established. Übermaßpassungen are widely used in engineering applications where a strong, permanent, and vibration-resistant joint is required. Examples include fitting gears and bearings onto shafts, assembling crankshafts, and in the construction of certain types of tools and automotive components. The design and selection of appropriate interference values depend on factors such as material properties, operating loads, and desired assembly method.