Pexco LLC, an Alpharetta, Ga.-based extruder of profiles and sheet, is working with Whiting Door Manufacturing Corp. to take the weight out of those roll-up doors on the back end of truck trailers.
Whiting Door of Akron, N.Y., claims to have developed the first overhead roll-up doors for trucks and trailers in 1953. The new door, boasting thermoplastic panels, is called the Shield series.
Pexco's engineering team created a customized product to meet strict tolerances, withstand harsh weather conditions and cut the weight of a 190-pound roll-up freight door by 20 percent. Traditional doors use sheet metal over a plywood core. But Whiting specified the new panels should be coextruded and made from ABS, since the material combines strength with rigidity and toughness.
Pexco engineering teams from its plants in Yakima, Wash., Philadelphia and Athol, Mass., worked with Whiting Door. Pexco engineers developed a coextruded panel of ABS and out an outer capstock layer of Sabic Innovative Plastics' Geloy XTW acrylic styrene acrylonitrile.
There is no need to paint the panels, since the capstock material can be color-customized. Also, the color will not fade because the coating polymer has protection from ultraviolet light, so it retains color and gloss, according to Pexco.
“This product innovation required a focused team effort and ongoing dialogue between our engineering team and Whiting Door,” said Edward O'Brien, Pexco's sales manager for custom products. “The result is an achievable extrusion product that is 20 percent lighter than traditional doors and meets the requirements for an industry-leading roll-up door that is sturdy and able to carry custom colors or graphics.”
They provide a weather-tight seal, the panels are contoured along the edge during the extrusion process, providing a tongue-and-groove channel that accepts a joint seal during door assembly. Integral steel inserts replace the traditional plywood core, serving as a webbing to provide stiffness, stability and a solid backing for the hinge fasteners.
The exterior face of the door is completely smooth, since the inserts are connected to the interior using pop rivets. That clean look is a big advantage, allowing customers to add graphics.
A key challenge for Pexco: the requirement of a tensile webbing design, which could be displaced or dislodged during repeatedly rolling up and down. Whiting's design does not have the exterior stiffeners that are used in competitors' truck doors.