Press fit

An interference fit refers to a connection technique in which a cylindrical component (e.g. shaft or bushing) is connected to another component (e.g. hub or housing) by pressing it on. The outer diameter of one component is dimensioned in such a way that it fits into the inner diameter of the other component, but must be pressed in with a certain pressing force.

Dimensioning and tolerances

The dimensioning of a press fit takes into account the specific requirements of the application, such as torque transmission, axial loads and environmental influences. The tolerances are kept tight to ensure an optimum fit and secure fixing.

Advantages of a press fit

Press fits offer several advantages:

• High strength: The press fit creates a robust and resilient connection.
• No additional fastening elements: reduction in the number of parts and costs.
• Maintenance-free: Once fitted, the press fit generally requires no further maintenance.

Applications of press fits

Press fits are used in various applications:

• Transmission shafts: Connection of gears and shafts in gearboxes.
• Bearing housing: Fixing of bearings in housings.
• Hydraulic cylinders: Connection of piston rods with cylinder tubes.

Production and assembly

The production of press-fit connections requires precise machining techniques such as turning, grinding or honing in order to achieve the required tolerances and surface finishes. Assembly is often carried out by pressing or cooling assembly, in which the temperature-related expansion difference is used.