Constant-Pressure Preload

A constant pressure preload is achieved using a coil or leaf spring to impose a constant preload. Even if the relative positions of the bearings change during operation, the magnitude of the preload remains relatively constant.

A preload diagram for duplex bearings under a constant-pressure preload is shown in the figure. The rigidity of springs is much less than that of bearings. As a result, the rigidity under a constant-pressure preload is approximately equal to that for a single bearing with a preload Fa 0 applied to it.