Plastics Today: Additive Manufacturing Takes Conformal Cooling to New Heights with PTC Creo

Conformal cooling is an analysis to establish the most effective uniform cooling of injection molded parts. This generally results in a more complex cooling channel arrangement than can be achieved by conventional machining.

Additive manufacturing techniques allow the cooling channels to be made exactly as the analysis demands, without the limitations that normal machining techniques have in following complex cavity geometry. This results in quicker, more-even cooling of the plastic and, hence, cheaper, more-accurate products.

Conformal cooling is made possible by using an additive manufacturing process, where metal powder is melted by focused laser beams, layer upon layer. These layers are built up and joined together as a solid block via direct metal laser sintering (DMLS). The layer thickness can vary down to 0.02 mm, depending on the finish required, balanced against the time and cost of manufacture.

A solid metal part is produced without limitations in its internal or external geometry. This allows cooling channels of any shape of to be built into the part (following the cavity shape). The external geometry can be machined and polished to ensure the molding surface has a smooth finish.

Object with conventional cooling channels.

Object with conformal cooling channels, possible with additive manufacturing methods.

As a policy, RPM International Tool & Die [New Zealand’s largest toolmaker] computer models all tools in 3D CAD, currently PTC Creo. This means that all thermal and flow simulations and water channel design can be accurately modeled and analyzed no matter how complex the geometry. With 5-axis machining and laser sintering, these 3D CAD models are accurately reproduced in metal with no geometrical compromises. Read more.