Manual trimmers are used effectively by employees to remove excess material from the formed parts.

While a silver-lining is often the indicator of success, for Lapeer, MI-based Durakon Industries, that liner is made of high-density polyethylene.

Durakon Industries is the world's largest producer of light truck bedliners which it manufactures and markets under the Duraliner, AllStar and Bodygard names. Durakon also manufactures the DuraSport line of cargo-protection products for light trucks, sports utility and cargo vans, as well as soft and hard tray liners, trim panels and pickup truck and SUV steps and running boards.

"The 'Dura' in the Durakon name stands for durable," says Craig Parr, senior vice president of manufacturing at Durakon Industries, and also president of Bodygard and Duramex, both of which are wholly-owned subsidiaries of Durakon (see sidebar on company background, page 20). A publicly-traded company (Nasdaq DRKN), Durakon posted sales of $192 million for 1998. Thermoforming sales accounted for approximately half that figure, or $96 million, Parr says.

More than 200 different styles of high-density polyethylene (HDPE) pickup truck bedliners are currently manufactured. While they tend to differ in terms of dimension, "each manufacturer also has his own specs," Parr says. "For example, on the Ford liners, the company's logo is prominent in the front of the liner and there is also a unique tie down arrangement." Durakon is the exclusive OEM supplier of liners for Ford pickup trucks sold in the United States and Canada. As both a tier one and tier two supplier, Durakon is also an OEM supplier of liners for other big auto makers, including Chrysler, GM, Mazda, Nissan and Isuzu. "We also sell a lot in the aftermarket to distributors," Parr adds.

"One of the things that sets us apart is that we have three-day delivery anywhere in the United States, which does require holding some inventory," Parr says. Product is shipped principally by truck, with rail used for shipping to the West Coast.

While Durakon does substantial business in the commercial van market, including interior panels, the company's primary market remains pickup truck bedliners &emdash; specifically Duraliner, AllStar and Bodygard.

All plastic products are made from HDPE, which the company extrudes for its own use. "For our product, HDPE is paramount. It's tough and lends itself well for thermoforming," Parr says. Durakon purchases its resin from Paxson and Solvay.

Because the company manufactures all its own sheet product, the extrusion lines run continuously, three shifts a day, seven days a week. Durakon has three HPM extrusion lines at the 325,000-square-foot Duraliner (Lapeer) facility, plus an additional extrusion line at its 50,000-square-foot Duramex plant in Lerma, Mexico. All of the sheet extruded in Lapeer is strictly for internal use in the company's manufacturing plants. However, Parr adds, Duramex does sell some of its surplus HDPE to other Mexican manufacturers.

Vehicle Accessories To Tow Trucks Like most success stories, Durakon Industries began with a vision. "The company was founded in 1979 by David Wright and Mike Wayne. They had an inspiration and a need to create products &emdash; a dream which has turned into reality," says Craig Parr, senior vice president of manufacturing at Lapeer, MI-based Durakon Industries. Since 1982, it has grown to become the number one manufacturer of pickup truck bedliners, serving as both a tier one and tier two supplier to major automotive makers. Under the leadership of David Wright, president and CEO, Durakon has become the exclusive OEM supplier of liners for Ford pickup trucks sold in the United States and Canada. It is also an OEM supplier to Chrysler, GM, Mazda, Nissan and Isuzu. In addition to its liners, the company also produces cargo van interior trim panels and accessories. Durakon has three manufacturing facilities in Lapeer, MI, Clinton, TN, and Lerma, Mexico for the manufacture of its automotive accessories. The primary product lines include: • Duraliner bed liner: the company's high-end liner with features including gripper surface and reinforced front panel. • AllStar and Bodygard liners: also high quality, these liners compete in the more price-sensitive markets. Both are sold through a large distributor network. • DuraSport: a complement to Durakon's bedliners, this line of cargo-protection products includes protective liners for the back interiors of sport utility vehicles and mats. In addition to the vehicle accessories market, Durakon has also made its mark in the towing and recovery vehicle segment. Jerr-Dan is a top brand of towing and recovery vehicles, offering a full-line of rollback carriers and wheel-lift towing vehicles. Durakon purchases the chassis and manufactures the remaining components at its Greencastle, PA, facility. Among the products produced under the Jerr-Dan label are: ZOD wheel-lift for rollback car carriers, Stingray model of high-end carriers, and medium- and heavy-duty tow trucks. The line is sold through a network of independent distributors.

To maintain consistency and quality control, both plants run similar extrusion processes. Sheet is extruded in gauges ranging from 125 through 280, in varying lengths for use in the thermoformers. The standard color for the material is black

Having the extrusion lines in-house helps the company not only maintain quality control, but its high production rate as well.

In the Lapeer plant, a dozen thermoforming lines run during the three shifts to form Durakon's HDPE liners; 10 are Brown Machinery formers and two are Maac Machinery. Overall, the company operates 19 thermoforming lines within its three plastics manufacturing facilities (Clinton TN, Lerma, Mexico and Lapeer, MI). "We anticipate expanding that by a couple more lines within the next year," Parr says.

"Currently, (at Lapeer) we have four-station rotary formers (two Maac and two Brown), while the remainder are inlines of various configurations," says Jeff Garceau, plant manager. "Our big inline thermoformer can handle 14-foot sheets."

On the inline molders, single sheets of HDPE are heated to 400F, placed over a mold and formed. The formed liner must cool in place before the process can be repeated.

The forming cycle typically runs approximately four minutes on a manual former and three minutes on the rotary.

On the rotary formers, parts are formed in a higher production, continuous cycle. Sheets are positioned on the former, then rotated into the oven and heated to approximately 400F. The flexible material is next rotated into the mold station and vacuum is applied, forming the sheet to the mold. After forming the liner is cooled and moved to the trimming cell.

The company uses CAD/CAM programming to design its patterns for molds. Wooden patterns for tools are manufactured in the plant's woodworking shop by a dedicated staff of trained mold makers. "We'll take a part, measure and scale it, add shrink (depending on whether aluminum or fiberglass tools) then measure off the part," explains mold maker Dan Girlish. This process can take anywhere from one day for small jobs, "to three months for a van panel set."

Durakon currently inventories more than 200 truck bed molds for use on the inline and rotary formers.

After forming, parts are transported to trimming cells. In addition to manual trimmers, the company also uses Motoman robotic trimmers equipped with Bosch end-of-arm routers to trim excess material from the parts.

According to Garceau, the robotic trimmers work in tandem. After clamping into place, holes are cut into the formed liners for attachment to the truck. Then, one robotic trimmer trims the tailgate section while another trims excess material from the liner perimeter. According to Garceau, the entire process takes less than five minutes.

"We use both carbide-tipped and solid carbide cutting tools," Garceau says, "though we tend to use more solid carbide tools because of their longevity."

Each operator and/or cell technician is responsible for an hourly quality control check, "which comes out to approximately 12 to 15 parts per hour," Garceau says. Floor supervisors and process technicians also perform random quality control checks.

"The appearance of the trim is very important. You also want the trim to be non-injurious (i.e., no sharp edges) to the person installing," Garceau says.

Maintaining a high standard of technology and quality control is very important to the company, Parr says. Durakon is ISO 9002 QS 9000 certified and is considered the number one bed liner company for all of North America, he adds.

As Parr says, with the company motto, "Winning with technology," what else would you expect?

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