FAG Hydraulic nuts HYDNUT are used to press parts with a tapered bore onto a tapered seat. They are mainly used if the drive-up forces required cannot be applied using other accessories, e.g. shaft nuts or pressure screws.

Hydraulic nuts are used mainly for the assembly of rolling bearings with a tapered bore. The rolling bearings can be seated directly on a tapered shaft, on an adapter sleeve or on a withdrawal sleeve. If the bearing is fitted using a withdrawal sleeve or an adapter sleeve, the hydraulic nut can also be used for removal.

A hydraulic nut is also suitable for the assembly and loosening of press-fit parts such as ship propellers, rudder blades, shaft couplings and toothed gears.