Theoretical modelling of the self-tapping screw fastening process

Abstract

The results of a theoretical study of the self-tapping screw insertion process are presented. Fundamental concepts of engineering mechanics are employed to analyse the axial torque required to complete a general self-tapping screw insertion operation. Equations for the screw insertion torque as a function of screw, hole and material properties are presented. Experimental results for torque signature signals are compared with the predictions of the theoretical model, con®rming the validity of the model. The theoretical model provides a basis for developing automated monitoring and control strategies for self-tapping screw fastenings.

Online Identification for the Automated Threaded Fastening Using GUI Format

“…This methodology has been applied with the appropriate ability for this work on simulation tests and experimental tests . This paper has used the mathematical model that is presented in (Seneviratne et al, 1992); (Seneviratne et al, 2001); . A model of the self-tapping screw fastening process has used the equation of five stages.…”

“…These self-tapping screw sizes are the most common sizes in manufacturing. The corresponding theoretical profiles of a curve of the torque signature signal and rotation angle for each set of insertions have been also generated using the mathematical model by (Seneviratne et al, 2001). The mechanical properties of the plate materials have used the theoretical model that was obtained from (Ngemoh,1997).…”

A Neural Network Clamping Force Model for Bolt Tightening of Wind Turbine Hubs

“…Various models of bolt tightening have been already reported in the literature: some of them were model-based or model-free controllers [25][26][27], the latter bypassing the need to estimate the parameters of the physical model [28][29][30][31]. For instance, in [25], authors presented the equations of screw insertion torque in function of the screw itself, the hole and the properties of the material; then, a theoretical model was validated by comparing experimental data with predictions of the model, providing basis for computerized monitoring of screw fastenings.…”

“…For instance, in [25], authors presented the equations of screw insertion torque in function of the screw itself, the hole and the properties of the material; then, a theoretical model was validated by comparing experimental data with predictions of the model, providing basis for computerized monitoring of screw fastenings. Other approaches attempt to tailor the values of the model parameters according to physical observations: Izumi et al [32] developed a finite element analysis approach describing the interactions between the threads of bolts and nuts during their tightening and showing as previous theory overestimates the tightening torque.…”

Analytical study of maximal tapping torque during forming screw process

“…1: screw engagement, screw advancement, and tightening. For each phase, Seneviratne et al (2001) proposed a model based on a quasi-static analysis which was set up to establish the respective tightening torque, screw engagement torque and screw advancement torque, which could be further decomposed into thread forming and friction resistance components. Two experimental samples, one made of thermoplastic plates (ABS) and the other of polycarbonate, with circular core screws and triangular cross section threads were used to validate the model.…”