Tensioning device for extending a threaded bolt

US10239194B2 · kind B2 · utility

Inventors

• Frank Hohmann · Warstein, DE
• Jörg Hohmann · Meschede, DE

Key dates

• Filing date: Mar 18, 2016
• Grant date: Mar 26, 2019
• Expiry date: Mar 23, 2037

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16B31/043
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A tensioning device for a thread end portion of a bolt has a cylindrical housing and a piston, moveable in longitudinal direction therein and connectable to a hydraulic supply. An interchangeable sleeve extends centrally through the piston. At its end it has an internal thread with engagement length to be screwed onto the thread end portion. The sleeve has a radially expanded portion carried axially by a carrier face of the piston. In order to prevent the sleeve from prematurely contacting the threaded bolt when mounting the bolt tensioning cylinder and prevent damage to the threads, the sleeve is moveable longitudinally relative to the piston. The longitudinal sleeve travel is defined by the carrier face as first longitudinal stop and by a second longitudinal stop. The longitudinal sleeve travel is at least equal to, preferably greater, than the engagement length of the internal thread of the sleeve.