Patent attributes
A tension device for straining a threaded bolt by applying a pulling force on a threaded end portion has a housing and a piston moveably disposed therein. A hydraulic supply is connected to the housing. A supporting tube is arranged on the housing. The supporting tube is arranged between the housing and a base surrounding the threaded bolt and transmits tension forces acting in the housing to the base surrounding the threaded bolt. A pull nut to be fastened by threaded engagement on a threaded end portion of the threaded bolt is provided. The pull nut has a pressure face supported in longitudinal direction on a pressure transmission face of the piston. A return spring acting on the piston in a direction toward the supporting tube has a first end bearing against a housing-side spring support and a second end bearing against a piston-side spring support.
