Record Crowd at Molding 2017 Hears News in 3D Printed Molds & Conformal Cooling
Two of the hottest topics in tooling today are additive manufacturing (3D printing) and conformal cooling—often with the former as a means to the latter.
Matthew H. Naitove
Executive Editor, Plastics Technology magazine
Both subjects were on the agenda at last month’s Molding 2017 Conference in Charlotte, N.C., sponsored by Plastics Technology. The two-and-a-half-day event, devoted entirely to injection molding, drew a record crowd of 261, beating the previous year’s record attendance of 235.
A return appearance by Scott Kraemer, directing manager of new technology for custom molder PTI Engineered Plastics, Macomb, Mich., wowed the audience, as he did at Molding 2016, with examples of his firm’s imaginative exploration of the possibilities of tooling inserts laser sintered from metal powders.
One of his examples, which he invited the audience to inspect and touch, was a cavity block that incorporated not only conformal cooling but also rows of deep grooves in the back side that allowed for air cooling and saved both moldmaking material and build time.
Another of Kraemer’s experimental parts utilized two laser-sintering programs to build a single metal part with two different final densities. In this case, the central cavity portion was only 90% as dense as the surrounding block.
This allowed sufficient porosity in the cavity area to permit venting directly through the porous steel, without the need to relieve vent lands (similar to using Porcerax sintered mold steel). In fact, Kraemer hooked up a line to the cavity area to suck out air during molding and then to blow compressed air through the insert to clear out the pores after part ejection. (Learn more about Kraemer’s and PTI’s work on 3D-printed molds and conformal cooling here.)
For molders and moldmakers who want to avoid climbing the learning curve of additive manufacturing, a new alternative was presented at the conference by William Sames, CEO of HTS International Corp. His firm, formerly based in Austria, has set up new headquarters in Knoxville, Tenn. HTS is offering standard tooling components, branded iTherm, which incorporate conformal cooling and are made by a proprietary additive manufacturing technology used exclusively by HTS. This Innovative Metal Fusion Technology (iMFT) has been in development for over 10 years and has been used industrially since 2014. Sames would not reveal details, other than to say the process does not involve deposition of metal powders.
His firm is offering mold plates, tool inserts (near-net blanks for cavities or cores), and sprue bushings in a range of standard dimensions. All incorporate conformal cooling and are made with standard Uddeholm tool steels, such as Stavax and Mirrax. Sames cited three case studies. One was thin parts for an auto dashboard, molded in four cavities with a cold runner. The iTherm sprue bushing reduced cycle time from 36 to 31 sec, a 14% saving, in the first trial. A second case was cutlery molding in six cavities using four iTherm inserts and a sprue bushing. Trials reduced the cycle by 23% to 41%, from 6. 5 sec to a range of 3.8 to 5 sec. Third, the cycle time for a large pipe elbow was cut from 256 sec to 116 sec, a 55% savings.
HTS is currently working with Oak Ridge National Laboratory in Oak Ridge, Tenn., to expand the range of alloys available and the range of applications for iMFT technology.
See the original article here.