Research on prediction model of slot milling forces for hollow thin-walled welded structural parts

Abstract

The milling force of hollow thin-walled welded structural parts varies greatly at each position, and the analytical model was less studied, which affects the prediction accuracy of milling force. In order to construct an analytical model of the milling force, a model was constructed to calculate the cutting depth of the tool slot milling based on the contact relationship between the cutter and the workpiece. Moreover, based on the structural properties of the hollow thin-walled welded structural parts, the effective cutting depth function at different locations was derived by using infinitesimal element integration method, and the dynamic milling force prediction model was solved at each location. Furthermore, the differences between the theoretical and experimental values were compared and analyzed from the viewpoint of the peak value and the trend of the milling force, and the chip thickness was verified. The results show that the milling force is minimal in all directions at the position of the upper and lower skin zone, and maximal at the position of the inclined rib zone. What’s more, due to the large cutting depth at the position of the vertical plate zone, the milling force in X direction increases first and then decreases, and continue increases at the position of the vertical plate zone, besides, the milling force in Y and Z directions increases first and then decreases. What’s more, the prediction errors of the forces in X, Y and Z directions at the position of the upper and lower skin plate zone are 7.01%, 2.04% and 8.24%, respectively, the prediction errors of the forces in X, Y and Z directions at the position of the inclined rib plate zone are 3.22%、8.76% and 7.77%, respectively, and the prediction errors of the forces in X, Y and Z directions at the position of the vertical plate zone are 7.01%, 2.04% and 8.24%, respectively.

Keywords

• dynamic milling force
• thin-walled structure
• infinitesimal element integration method
• slot milling
• cutting depth function