Conventional injection molds are machined from tool steel. Their drilled cooling channels (DCC) are interconnected straight sections with circular cross-sections. For complex parts significant temperature differences often exist throughout the tool. By building mold inserts as electroformed nickel shells backed with conformal cooling channels (CCC) encased in copper, the mold temperature is more uniform. High thermal conductivity mold materials and CCC reduce hot spots, decrease cycle time, increase productivity and reduce part distortion. Case studies document actual productivity gains of 67% and 75%. Finite element analysis results are shown for an H-13 steel/DCC mold, as well as an otherwise identical geometry Ni-Cu/CCC mold. Mold temperature distributions and process cycle times are examined in detail.
| Number of Pages : | 18 |
| Published : | 11/01/1999 |
