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moldmakingtechnology.com 21 FOR MORE INFORMATION Pat Zaffino / Managing Director / Conformal Cooling Solutions pzaffino@conformalsolutions.com / conformalsolutions.com This part-deflection study of the conformal-cooled bumper mold shows the deflection of the molded part in the various planes. The X plane shows more even shrinkage across the part, minimizing warpage (including the ends of the part). The Y plane has the part being more evenly cooled in the midsection and across the face. It also shows the part being pulled toward the cavity due to the effective cooling of the core, which assists with demolding. The Z plane shows the part maintaining an even deflection with minimal warpage. Note that the ends are deflecting inward, which eases installation during assembly. could require 50 to 100 baffler/bubbler holes, which are drilled from the bottom of the mold up toward the molding surface where coolant passes through the baffle system. The drilling is time-consuming and uses an enormous amount of space in the mold, which limits a designer's ability to place other mecha- nisms, such as lifters and ejector pins into the mold. Using this robotic multilayer deposition system for confor- mal cooling can eliminate the majority of the baffles or bub- bler systems, which in turn reduces gun drilling and tapping by 75 percent, according to Zaffino. This increases design flexibility for other mold mechanisms and permits cooling channels in the core half of a mold. Cooling channels can also be placed in the lifters and slides and can closely follow the surface contours for maximum cooling effectiveness. A channel is machined in the core molding surface and the multilayer deposition system closes this channel to cre- ate a closed chamber for water flow. The channels are now a consistent distance from the molding surface, which provides predictable cooling of the mold surface and reduces cycle time. The most efficient way to deposit any alloy, Zaffino says, is in the flat position, so that gravity is not a factor. The conformal cooling channel is orientated by the system, so it is perpendicular to the floor. This ensures that the bead sequence is consistent within the channel. There are set stan- dard operating procedures within the system. For example, if the channel receives 24 beads for a 0.750-inch channel, there will be 100 percent consistency for all similar channels of the same dimension. The only variation would be the length of the channel. For this process, 0.500- and 0.625-inch channels have been implemented. A simulation study was conducted using Autodesk MoldFlow Insight to determine the impact of conformal cooling channels produced via the multilayer robotic depo- sition system. The findings report that conformal cool- ing created a more even temperature across the molding surfaces, reducing cycle time and improving part quality; circuit pressure with conformal cooling reduced pressure by a factor of 20 times throughout the circuit; and, the mold interface temperature with conformal cooling resulted in a 25.5°F-temperature reduction, better dimensional stability, the elimination of hot spots, quicker production startup and less material waste. In addition, a part deflection study indicated more even linear shrinkage across the length of the part, and more even cooling across the center portion of the part that featured the largest surface area. Finally, the study found more even dis- tortion in the Z plane and minimized warpage. This patented process was tested and proven in a mold that has produced more than 20,000 fascia bumpers. The cycle time was reduced by 25 percent compared to the convention- ally-cooled mold. "We are encouraged by these results and believe that it could greatly benefit molders through improved cycle times, provide better part quality, increased press utiliza- tion rates and decreased energy use," Zaffino says. Conformal Cooling — Deflection