Modeling dynamics of parallel turning operations

Parallel turning operations are advantageous in terms of productivity since there are more than one cutting tools in operation. However, the dynamic interaction between these parallel tools may create additional stability problems and the advantage of parallel turning may not be utilized to full extent. For that reason, dynamics and stability of parallel turning processes need to be modeled. In this paper, dynamics of two different parallel turning operations where two turning tools cut a common workpiece are modeled. In the first case, the tools are directly coupled to each other whereas in the other case the coupling occurs through the vibration waves left on the workpiece. For these two cases, stability models in frequency and time domain have been developed. The frequency and time-domain solution results are compared and a reasonable agreement is observed. The predicted stability limits are also compared with experimental results where good agreement is demonstrated.