MISSISSAUGA, ONTARIO — The demand for processors to make quick mold changes is drawing more companies toward magnets.
A series of electronically controlled magnets can provide all the power needed to hold even large molds in place, and do it in a fraction of the time it would take to do any standard clamping, said Simon C. Barton, developer of Staubli Corp.'s magnetic quick-mold-change system.
"Most people's thoughts about magnets are that, `Well, I've got some on my refrigerator,'|" Barton said May 1 at Plast-Ex 2001 in Mississauga. "They can't imagine that it can hold a mold that weighs thousands of pounds."
Staubli introduced its system in Europe late last year and in North America in February. It already has 15 contracts in hand, including one that will rely on magnets to hold a 55-ton mold in place, Barton said.
Staubli is among a small, but growing, number of companies producing such systems, which work around the same basic principle as refrigerator magnets to hold steel molds in their position but on a much larger scale.
"As long as it's a steel mold, I can hold it," Barton said.
The system also would work on an aluminum mold with a steel outer structure, he said.
Staubli is producing its electronically controlled magnetic systems, which can be retrofitted onto platens of existing presses, at its North American base in Duncan, S.C.
The company makes other quick-change systems but is focused now on magnets, Barton said.
The concept is taking off among processors for the auto industry, where automakers are demanding a greater variety of trim packages to meet consumers' requests for more flexible-style packages, he said. Carmakers want a quick switch that can fit into a just-in-time delivery system, while molders want to keep the presses in action without storing dozens of potential styles.
"Inventory is now the enemy," Barton said.
A molder may have only a few hours' notice to switch production, he noted. Magnets take just minutes to put a new mold in place — and less than a second to clamp it down — compared with two or more hours for most large molds.
And Barton maintains the magnets provide a more consistent grip than standard clamps, exerting the same force over the entire surface every time.
The company is in talks with machine makers to design future presses around the magnets. The company also is considering ways to make the same program available as a quick-change option for other molding techniques as well, he said.