Modeling and simulation of the geometry and forces associated with the helical broaching process

Helical broaches have a very complex geometry, and some of them have hundreds of teeth with different sizes and spatial positions. This paper describes the geometric modeling of a helical broach using the equations that represent this geometry. This mathematical modeling is carried out using a MatlabA (R) code and the results are compared with a CAD model, which is adopted as a reference. The Kienzle equation is then used to obtain the traction force and torque acting on the broach shank. Experiments were performed to determine the Kienzle equation constants using the longitudinal movement of a CNC lathe with low cutting speeds. Very close results were found comparing the geometric model with the CAD drawing, and the Kienzle constants obtained are consistent with those described in the literature, which implies that the resultant traction force at the tool shank during a real process is close to that predicted in the simulation.