More molders choosing magnetic clamping systems
Several suppliers of magnetic, quick mold change (QMC) clamping systems reported a high interest level in their products at the recent Plast-Ex and Mould Source show in Toronto. Staubli Corp. introduc...
Several suppliers of magnetic, quick mold change (QMC) clamping systems reported a high interest level in their products at the recent Plast-Ex and Mould Source show in Toronto. Staubli Corp. introduced its QMC-121 magnetic system for electro-magnetic clamping of molds in injection molding presses. As well, Tecnomagnete’s Quad-Press 75 magnetic platen and QMC system was installed on an operating Van Dorn Demag 1100-ton, two-platen Caliber injection molding press, where it was used to hold a 6.5 ton tote-box mold in place.
While both magnetic clamping systems operate similarly in principle, reducing mold change time to as little as 10 minutes, each has distinguishing design features, some of which are summarized in the table below.
Peter Stephen, president of Stephen Sales Group, the Canadian sales representative for Tecnomagnete for plastics applications, says one of the major benefits of the magnetic clamping system in comparison to hydraulic QMC systems, is that it eliminates the need for a special back plate for every mold size. Such plates can add as much as $10,000 per mold to the cost of a conventional QMC system. Stephen says he has recently sold six sets of the Tecnomagnete QP-75 system to a Seimens facility and is also retrofitting 11 machines for a Canadian-based Textron operation.
Staubli’s Simon Borton says the design of QMC-121 magnetic pole system increases the concentration of the magnetic force nearer to the center of the mold. Also, at 49 mm in thickness, the platen width is the smallest on the market, which means a molder gives up less in overall mold height. In addition, Borton says, the QMC-121 has a safer design which incorporates a “flux sense” sensor, rather than proximity switches, to measure magnetic force inside the platen’s magnets. If there is an improper clamp or other error an alarm flashes and the machine cycle is stopped.
“Our system takes away responsibility from the operator for making a judgment of whether the machine is safe to run or not,” says Borton.
|Feature||Tecnomagnete QP-75||Staubli QMC-121|
|Platen thickness||52 mm||49 mm|
|Maximum depth of magnetic field||20 mm||10 mm|
|Sensor accuracy||0.2 mm||0.1 mm|
|Maximum working temperature||120* C||100* C|
|Type and size of machine||All||All|
Staubli Corp. 864-433-1980
Stephen Sales Group