A SCHAAF Hydraulic Nut of this design has a circular groove which is sealed to the exterior by an axially sliding ring piston and, thus, forms an annular hydraulic chamber. When pressurized, the ring piston is pushed out, contacts the counterface and generates an axial pressure force. Since the ring piston is self aligning it can, within certain limits, adapt to errors in run-out and to an uneven counterface. This characteristic offers a great advantage, in a lot of applications.
In the case of the Hydraulic Nuts, type A 4601 and A 4651, the pressure is generated by turning an actuator screw with a simple Allen key, which, in turn, displaces the actuator piston. The nominal clamping force has been achieved as soon as the Pressure Indicator Pin is flush with the face of its cartridge.
- Stroke limited to 2 mm or 4 mm max. resp. (bigger stroke on request)