On Systematic CAD/CAM Modeling of Blow Molds for Plastic Bottles

摘要

A systematic and detailed approach in design and manufacturing of blow molds for bottles made of PET and PP plastic material with CAD/CAM software tools is presented, as many production errors and product deficiencies stem from inaccurate and imprecise tooling. Apart from high mold accuracy, proper planning also includes the minimization of mold machining costs, which mainly derives from CNC machining time and cutting tool wear. Blow mold design and manufacturing revolves around two major axes: (a) mold material and (b) machining parameter values. The former is critical in terms of production rates and mold life-cycle and the latter has a great impact on mold manufacturing cost, as well as on quality of the produced plastic bottles. Proper choice of machining parameters has a significant impact on thermal conductivity, durability, hardness, stiffness and roughness of the mold. The proposed methodology was implemented on three different test cases (beverage plastic bottles molds) and it was concluded that even the same machining parameter values offer the same mold quality.