Stud tensioning device, in particular for the bolting of covers and in particular of pressure vessels of reactors.

摘要

Apparatus for tightening and releasing nuts on screw-threaded studs to fit or release a cover on a pressure vessel employs several devices each for subjecting a respective one of the studs to tension to clamp the stud whilst the nut is rotated thereon. Each device employs a coupling mechanism for clamping a rod-like extension piece in end-to-end relationship to one of the studs to apply tension force thereto from a hydraulic piston and cylinder unit. The coupling mechanism takes the form of a sleeve containing several arcuate coupling segments guided for displacement radially of the stud and its extension piece. Cam surfaces on the coupling segments and the sleeve inter-engage as the sleeve is rotated to effect the displacement of the coupling segments between open and closed positions.