Patent ID: 6134973
Filing Date: 2000-10-24
Classification: B25B

Abstract:
A method for controlling a screw joint tightening process wherein the screw joint is to be tightened to a predetermined torque level by means of a torque impulse delivering tool, comprising:measuring an instantaneous value of an applied torque delivered to the screw joint during each one of a number of succeeding torque impulses delivered to the screw joint,detecting continuously a rotational movement of the screw joint during each one of said torque impulses,indicating when the rotational movement of the screw joint ceases at each impulse,indicating a value of the applied torque at the instant the rotational movement of the screw joint ceases at each impulse,comparing the indicated value of the applied torque at cessation of the screw joint rotation for each one of the number of succeeding impulses with said predetermined torque level, andinterrupting the tightening process as said indicated value of the applied torque reaches said predetermined torque level.