Compression-molded plastic parts outmuscle steel
Global Polymer uses a unique compression molding process that it developed to embed steel and other metals within ultra-high-molecular-weight polyethylene.
June 28, 2017
Producing plastic parts that are stronger than steel is the technical expertise of Global Polymer (Madison, SD), a compression molder that has earned a reputation for delivering innovative solutions for difficult manufacturing problems. Global Polymer uses a unique compression molding process that it developed to embed steel and other metals inside ultra-high-molecular-weight polyethylene (UHMW-PE).
Founded in 1995, the company operates from a 75,000-square-foot facility with the capacity, tooling and expertise to fulfill national and international orders. More and more manufacturers are using the steel-strengthened parts that are nearly indestructible, according to the company, including John Deere, SAF-Holland, AGCO, Luxme and Salco Products.
The lightweight, weather-resistant plastic is a good fit for the rail industry, said Keith Parta, New Products Manager at Salco Products, which manufactures train parts that, until recently, had been made only of metal. “We’re trying to introduce materials into the rail industry that offer a higher level of performance than metal, carbon or stainless steel,” said Parta.
Salco went to Global Polymer when it wanted to create a new type of blind flange—essentially, a cap for the end of a pipe—for use on tank cars. The part would be required to withstand the elements, high pressure, corrosive chemicals and rough handling. Global Polymer built the cap with compression-molded UHMW-PE embedded with steel.
The metal is key in allowing the plastic to maintain its shape without deformation, and offers a very high level of corrosion resistance and weight reduction compared with a full metal part, said Barta.
It’s also proving to be cost effective, said Global Polymer. The company’s process results in what the industry calls net-shape molding, meaning that the parts come out nearly perfectly shaped, requiring little or no trimming. That saves on production time.
The technology came in handy for customer Luxme International, which was in a rush to compete with copycats eager to cash in on Luxme’s innovative use of UHMW-PE parts in conveyor systems for food-handling applications. Using UHMW-PE parts to move the food eliminated exposed hardware—a requirement for food handling.