Designing Conformal Cooling Channels for Tooling

Abstract

SFF technologies have demonstrated the potential to produce tooling with cooling channels which are conformal to the molding cavity. 3D Printed tools with conformal cooling channels have demonstrated simultaneous improvements in production rate and part quality as compared with conventional production tools. Conformal Cooling lines of high performance and high complexity can be created, thus presenting a challenge to the tooling designer. This paper presents a systematic, modular, approach to the design of conformal cooling channels. Recognizing that the cooling is local to the surface of the tool, the tool is divided up into geometric regions and a channel system is designed for each region. Each channel system is itself modeled as composed of cooling elements, typically the region spanned by two channels. Six criteria are applied including; a transient heat transfer condition which dictates a maximum distance from mold surface to cooling channel, considerations of pressure and temperature drop along the flow channel and considerations of strength of the mold. These criteria are treated as constraints and successful designs are sought which define windows bounded by these constraints. The methodology is demonstrated in application to a complex core and cavity for injection molding.