How is preload in a bearing typically measured?

Preload in a bearing is typically measured using a torque wrench because this tool allows for the precise measurement of the torque applied to the bearing assembly. Preload refers to the initial load applied to the bearing, which helps to reduce play and is critical for maintaining proper alignment, load distribution, and operational performance.

When measuring preload, a torque wrench can provide the necessary readings that indicate how much force is being applied when tightening the bearing components. This measurement is crucial in achieving the ideal preload specifications as per the manufacturer's recommendations.

Using other tools, such as a digital multimeter, a straightedge, or a micrometer, is not suited for measuring the preload directly. A digital multimeter is generally utilized for electrical measurements, while a straightedge is used for checking flatness or alignment, and a micrometer measures small distances or thicknesses. None of these tools can effectively measure the torque or preload in a bearing setup.