When you go the same industry conference many times over the years, it seems like you've heard it all before, right? Wrong! Let Heavy Metal tell you a story. It's a tale of a math-whiz intern who led an advanced research and development at Centro Inc., a big rotational molder based in North Liberty, Iowa.
The Rotoplas show is the place where you can see everything rotational molding. Organized by the Association of Rotational Molders, the most recent version ran Sept. 26-28 at the Donald E. Stephens Convention Center in Rosemont, Ill.
Like any trade fair, the energy level is high on the show floor. Conference sessions? Sometimes not so much.
Rotoplas 2017 presentations covered familiar areas like design case studies, materials and something called "creep modeling," (No, this did not mean using Harvey Weinstein as your role model). Then there was "blending vs. compounding" — kind-of like Batman vs. Superman, but not quite as pulse-pounding.
Trust me when I say I've been to a lot of rotomolding events.
So I had low expectations when I sat down to hear this presentation: "Simplifying the Complex Thermodynamic Properties of the Rotomolding Cycle." Time for a fresh cup of coffee!
But it was great! If fits perfectly into the theme of finding skilled young people — with an unusual twist.
Dan Grimes, Centro's R&D engineer and advanced technology leader, took the stage to say that rotomolders need to keep pushing into new technology, but that can be a big challenge "especially if it's from the ground up."
Like magic, Shawn Trosen came to the microphone. He's a student at the University of Iowa. He proceeded to explain how he used complex math to help Centro figure out a way scientifically optimizing cure inside the mold.
One of rotomolding's biggest challenges is how to make an often-variable process more precise. The idea of "process optimization" is common in, say, injection molding. But rotational molding is a unique process where molds slowly rotate in big ovens, the plastic powder melting and pooling to coat the mold as it turns, then spins through a cooling station before operators remove parts.
Shawn admitted he knew nothing about rotomolding when he accepted an internship at Centro. They handed him a technical paper called "The Degree of Cure." And said have at it!
He studied cross-linked polyethylene. Specifically, how to manage the internal air temperature and create the best cycle parameters. He looked at things like the heating rate, and how you can trap bubbles in the part if you heat it too fast. But if heating too slowly, the process is not running as efficiently as possible.
Shawn wrote coding and a computer program to solve the challenge. Centro can use that to plan how to best run a part even before a mold is built.
When the college student flashed up a slide during the Rotoplas session, showing the mathematical formulas, it looked like something Albert Einstein would do. But for rotomolding! When he remarked how, oh, it's really not that hard to figure out, the rotomolders in the audience laughed.
(I flashed back to the C's I got in high school algebra).
The message of this story is this: Yes, the plastics industry needs to attract young talent. But the Centro case shows you should keep an open mind of the type of expertise. The shortage of mold makers, process technicians and service engineers gets all the attention.
Then you have someone like Shawn Trosen, college student. As Grimes said: "What began as a challenge to an intern is now an effort to do process optimization and scientific rotational molding."
