Shim Type ( Data Sheet DS 810 )

This nut has a flanged piston. A shim gap is created between the body and the piston when the nut is pressurised. The size of the shim gap is a combination of the compression of the bolted joint and gasket, if fitted, plus the elongation of the bolt.

In use the nut is pressurised until the hydraulic jack develops the desired pre-load. The shim gap is measured and shims are made to fit. The pressure is increased slightly to allow the shims to be inserted. The pressure is released and the pre load is transferred onto the shims. A very high percentage of the load is retained in the bolt. The shim type nut is the most accurate type of hydraulic nut.