Research on Bolt Tightening Control Method Based on Electric Tightening Machine

With the rapid development of manufacturing automation, traditional bolt tightening methods are difficult to adapt to the fast and high quality requirements of modern industry for product assembly. Even electric tightening has been put forward higher requirements, especially for those products that require high axis force control after bolt tightening. Therefore, it is particularly important to control the bolt tightening process and results. In this paper, three tightening methods are compared by experiments, and the torque-angle twice tightening method is chosen as the best one, which has the least attenuation and the minimum discrete rate of the axis force after 24 hours. Aiming at the difficult problem of how to control the axis force after tightening, a set of automatic control method using electric tightening machine is put forward. This method can accurately control the tightening position even if the workpiece with variable. At the same time, it can control the tightening process effectively by monitoring the relative relationship between tightening angle and Torque, in order to effectively ensure the modern manufacturing industry on Bolt Tightening axis force requirements.