Mwinuka, Tito E.; Mgwatu, Mussa I.
Description:
Most of CAD/CAM systems lack fully‐automated process planning capabilities
and depend on semi‐automatic capabilities that necessitate the traditional
selection of tools and cutting parameters. This paper attempts to determine
proper combinations of cutting tools through the generation of tool paths and
optimisation of machining parameters using an example of the CNC milling
process. Several machining simulations with different combinations of tool
sizes were performed using MasterCAM software. Based on these simulations,
substantial variations in tool paths were observed for different tool combina‐
tions and as such the optimum tool combination could only be obtained arbi‐
trarily. The tool paths derived from machining simulations were used to opti‐
mise machining parameters, that is, cutting speed, feed rate and depth of cut
with the objective of minimising production time. In this case, an optimisation
model was developed as a nonlinear programming problem and solved using
extended LINGO nonlinear software. The results show that the subjectivity
when selecting cutting tools can be avoided when appropriate tools are chosen
alongside with the generation of a tool path within a CAD/CAM system using
optimised machining parameters. As a consequence, CNC machine tools could
be effectively utilised and the productivity significantly improved at shorter
production time and cost.