Ferenc Szabó

Enhanced Injection Molding Simulation of Advanced Injection Molds

The most time-consuming phase of the injection molding cycle is cooling. Cooling efficiency can be enhanced with the application of conformal cooling systems or high thermal conductivity copper molds. The conformal cooling channels are placed along the geometry of the injection-molded product, and thus they can extract more heat and heat removal is more uniform than in the case of conventional cooling systems. In the case of copper mold inserts, cooling channels are made by drilling and heat removal is facilitated by the high thermal conductivity coefficient of copper, which is several times that of steel. Designing optimal cooling systems is a complex process; a proper design requires injection molding simulations, but the accuracy of calculations depends on how precise the input parameters and boundary conditions are. In this study, three cooling circuit designs and three mold materials (Ampcoloy 940, 1.2311 (P20) steel, and MS1 steel) were used and compared using numerical methods. The effect of different mold designs and materials on cooling efficiency were examined using calculated and measured results. The simulation model was adjusted to the measurement results by considering the joint gap between the mold inserts.

Development of a Novel Pvt Measuring Technique

The pressure-temperature-specific volume relation of polymers is important not only for physical chemistry, but they are very significant input data for injection molding simulation software. Todays methods for measuring pvT data are slow, measurements can take days to be carried out, and in many cases the accuracy of the measurement is unsatisfactory. In our work, a new measuring method has been developed which makes the determination of the pvT relation faster compared to conventional processes within injection molding processing conditions. For the measurements a special injection mould was developed, in which the pvT relation of the material can be determined from the shrinkage in the mold. The data measured by the new method using polypropylene at a mold temperature of 23°C were compared to the data given in the database of the simulation software.