The main task when designing a tool for roll-formed shapes cutting is to select the optimal configuration of the cutting knife, which shape should provide high-quality profile cutting, no defects in pre-end zones and the minimum cutting force. The main factor that can ensure these conditions is the angle of profile cutting.

To evaluate the impact of the cutting angle on the energy and force parameters of the process, the guillotining model was investigated, where the impact of angle ‘a’ on the force and energy of cutting was determined. The study was conducted in the program LS-DYNA.

 

Animations of the profile cutting process at different cutting angles (0, 10, 45, 85 degrees) are presented below. 

Waste forms are different at different cutting angles. Plasticity propagation in the cutting zone can also be seen. If deformation is mainly concentrated in the cutting zone at an angle of 10 deg., then at an angleof 70 deg. deformation is concentrated both in the cutting zone and across the most part of waste, and as a result we have an increase in the internal energy of cutting.

Selection of optimum cutting angles is associated with minimum costs for the applied force and cutting energy. Diagrams of the dependence of force and internal energy on the cutting angle were constructed. Then the diagrams were compared to find the optimum cutting angles, which presuppose the minimum force and internal cutting energy. As a result, it was found that the working range of cutting angles is8-33 degrees These values ​​can be used to design knives for roll-formed shapes cutting with minimum energy consumption.

LS-Dyna is well suited to model separation operations of metal forming processes. As a result of the research, stages of work piece deformation and separation during guillotining were studied, the optimum range of cutting angles corresponding to 8-33 degrees was found under conditions of minimum effort and internal energy of cutting, and cutting processes for certain roll-formed shapes were investigated.