A device for measuring the prestressing of a bolt 1 shows an axial half cross section that is used in particular to close an enclosure under pressure of a resonance

摘要

An apparatus for measuring the pre-tension of a threaded bolt by means of a two part measuring rod introduced into a central hole of the threaded bolt and of a length measuring device. The measuring rod includes an upper rod threaded to a lower tube which is secured against rotation. Rotation of the threaded rod by a motor moves the end of the measuring rod in or out of the central hole.