Thermoformer Is Reinvented Through Process Innovation

Four years ago, Durakon Industries in Lapeer, Mich., was focused almost exclusively on thermoforming HDPE bedliners for light trucks.

Four years ago, Durakon Industries in Lapeer, Mich., was focused almost exclusively on thermoforming HDPE bedliners for light trucks. As market leader in the category, it churned out around 900,000 units a year. Yet the company was on a slippery slope, with growth in bedliners slowing and competition strengthening. Its efforts to develop new products and attract more investment funds were stuck in neutral.

Today, just a third of Durakon’s $200 million annual sales is in bedliners, the rest coming from new products like tonneau covers, sidewall storage bins, bulkheads, and other cargo-management assemblies. The company has also become a pioneer in decorative exterior panels formed from thick TPO sheet with laminated paint films or coextruded color layers. The first such panels will appear soon on the new Chevrolet SSR two-seat roadster.

Durakon’s revival springs from its acquisition in 1999 by Littlejohn & Co., an investment firm in Greenwich, Conn. The buyer installed new management with a mission to diversify into high-growth sectors. New product development based on advanced forming concepts became a top priority.

“Interest among automotive OEMs and molders in our process variants is exploding,” says Edward Gniewek, Durakon’s CEO. He cites decorative TPO panels that permit OEMs to avoid the high costs and environmental headaches of painting. Another success story is tonneau covers that are twin-sheet formed with embedded aluminum-honeycomb reinforcements. “Our customers now realize that thermoforming goes beyond bedliners and dunnage,” says Gniewek.


Tonneau covers reinvented

Durakon’s rebirth gathered steam in late 2000 when General Motors adopted the firm’s reinforced TPO tonneau system for 2001 Avalanche light trucks. Twin-sheet forming with honeycomb reinforcement creates a strong sandwich structure that is 60% lighter than fiberglass composite. Durakon extrudes its own TPO sheet from A. Schulman resin. Sheets are formed on shuttle machines built by Advanced Ventures In Technology. During forming, a robot inserts Hexcel aluminum honeycomb reinforcement panels between the TPO skins. Then urethane foam is injected into the remaining space to increase load-bearing properties. Durakon developed a production cell for making finished parts in 60-sec cycles with zero defects. Special cooling chambers are used to help hold critical dimensions.

Avalanche trucks are made in Mexico in volumes of 110,000 a year with tonneaus and sidewall storage boxes as original equipment. To service GM, Durakon built a dedicated plant in Lerma, Mexico. Its other plants are in Lapeer and in Clinton, Tenn.

Two automotive transplant OEMs have signed on for two- and three-cover versions of the tonneau assembly on 2005 models. Ford plans to use a single-cover design for a new version of its F150 light truck.


Aesthetic enhancements

Durakon’s decorative TPO running boards and stone guards made their debut on the Chevy SSR in late 2003. Gniewek says they are the first such uses of thermoformed TPO with decorative paint films. The running boards are twin-sheet formed with a glossy silver paint film from Avery Dennison. TPO stone guards are single-sheet formed with Class-A pigmented surface.

Emerging programs include a front fascia for the 2004 Jeep Wrangler and rocker panels for the 2005 Buick LeSabre. Durakon is evaluating a number of decorative films and TPO compounds from various suppliers.

Another new launch is a cosmetically enhanced version of the company’s workhorse Duraliner HDPE bedliner. The new version has a 5-mil capstock thermally bonded to the substrate, yielding a rich, black, satiny surface with improved scratch and color-fade resistance.