The loads on the tie bars of a die casting machine are balanced to prevent flashing and tie bar failure. The distribution of the loads on the tie bars depend on the die footprint, die location, location of cavity center of pressure. The current die/machine setup guidelines uses only the location of center of pressure when determining the tie bar loads and moments. This approach assumes that the dies and machine platens are rigid. The objective of this study is to develop a regression model to predict the imbalance in the tie bars for given die and cavity setup and cavity pressure. The proposed model will also account for the elastic deformation of the dies and the platens. Seven factors namely, the die width, die height, cavity pressure and the die and cavity locations in the horizontal and vertical directions were studied. Five levels of each of these factors were considered and an experimental array with fifty runs representing different combinations of these factors was developed. For every treatment in the design array, the tie bar loads were predicted from static finite element simulations using ABAQUS FEA code and the load imbalances on the tie bars were calculated. A linear regression was performed on the data set with the seven factors as the predictor variables and the load imbalance on the four tie bars as the four response variables. The regression model is presented and the relative contribution of each of these factors on the tie bar load imbalance is discussed in this paper. The correlations between some of these factors are also investigated. The die location on the platen was found to be the most significant factor contributing to the tie bar load imbalance.
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