When installing a bearing with a press fit onto a shaft, where should the pressure be applied?

When installing a bearing with a press fit onto a shaft, applying pressure to both races evenly is essential for ensuring proper alignment and distribution of forces throughout the bearing. Pressing on only one race, particularly when using a significant amount of force, can lead to deformation or damage. This technique helps to maintain the integrity of both the inner and outer races, preventing issues such as misalignment or excessive stress that could ultimately shorten the bearing's lifespan or cause failure.

Maintaining balance in the pressure applied allows for smoother installation, reducing the risk of the bearing binding or seizing during operation. Moreover, this method supports the overall performance of rotating equipment, ensuring that the bearing aligns correctly with the shaft and housing.

When considering the other options, pressing on only the outer or inner race would risk introducing stress concentrations that can lead to premature failure. Applying pressure to a threaded shaft area is also inappropriate, as it may not effectively transfer the force needed for installation and could lead to damage at the threads or other structural concerns. Thus, applying pressure evenly to both races is the best practice for bearing installation.