Bayer MaterialScience's RIM System Replaces Metal For Exterior Excavator Component
Bobcat 430 and 435 ZHS Compact Excavators Feature Durable Right-Hand Hood Cover Molded from Bayflex Elastomeric Polyurethane RIM System
Pittsburgh - Bobcat Co. needed a tough, durable, yet aesthetically pleasing material to form the right-hand access cover for its 430 ZHS and 435 ZHS compact excavators. The company found what it was looking for in Bayer MaterialScience's Bayflex XGT-100 elastomeric polyurethane Reaction Injection Molding (RIM) system. The part covers the valve and other components on the right hand side for these two excavator models.
Bobcat traditionally used steel stampings for many of its excavator components. However, RIM offers design freedom that cannot be achieved with metal. "With the RIM process it is possible to mold parts with large, complex geometries that would be difficult to duplicate with steel," said Jeremy Harms, a Bobcat design engineer.
Bayer's Bayflex XGT-100 system features an extended gel time that gives equipment designers the flexibility to create large, complex parts that are strong, yet light weight. The material's excellent surface quality and high impact resistance make it a good candidate for agricultural and construction equipment – such as the Bobcat excavators – as well as heavy-duty trucks.
Romeo RIM molds the component, which is roughly 47 inches long, 26 inches high and 25 inches wide, utilizing the polyurethane RIM process and in-mold painting, in which paint is sprayed into the mold prior to injection. In the in-mold painting process, the injected polyurethane material bonds to the paint during molding, resulting in a decorated part with a Class A finish right out of the mold. By eliminating secondary finishing operations, such as degreasing, sanding, priming and post-painting, the in-mold painting process results in significant savings.
Molding in attachments, which minimizes secondary operations, is another opportunity for increasing efficiencies. "And unlike metal, a component molded with RIM materials won't rust, dent or corrode," explained John Geisler, manager, customer development for Romeo RIM. "Our engineers are very talented at designing parts that meet stringent performance criteria while achieving the desired aesthetic effect."
Over the years, Geisler has worked with Bayer polyurethane RIM materials in a number of different applications, so he knows first hand the benefits of working with the company.
"We have a good working relationship with Bayer," said Geisler. "Not only did their polyurethane material exhibit the properties we needed for this application, but their people were very knowledgeable, which also helped contribute to the success of this project."
SOURCE: Bayer MaterialScience LLC