Effect of cooling water flow rates on local temperatures and heat transfer of casting dies

In high pressure die casting processes, proper temperature control of a die yields high casting production rates and superior quality components. Die temperature is usually influenced by various die design and process parameters such as size and location of internal water cooling lines, flow rates of cooling lines, and pouring temperature of molten metal. Among them, the cooling water flow rate plays a major role in controlling thermal pattern of the die. In order to better understand the effect of water flow rates on die temperature, a computer-based data acquisition and control system (DACS) has been developed and employed to monitor and record data of internal water flow rates and local temperatures of an industrialized die insert installed in a die casting process simulator. The analysis of experimental information collected by the DACS indicates that the water flow rates influence die temperatures especially at the early stage of die cooling. However, the die heat removal rate tends to decrease as cooling time extends.