KENWORTH'S W900L TRUCK ADOPTS METTON(R) RESIN FOR ITS FIRST ADVANCED POLYMER TRUCK HOOD

ATLANTA (April 29, 2002) – Metton America, Inc. announces the introduction of Kenworth Truck Company’s first advanced-polymer, truck hood for its on-highway class-8, W900L model with curved windshield. The new hood provides reduced weight and performance enhancements over the current hood at no additional cost, while maintaining Kenworth’s traditional, long-hood look and design. Kenworth also is making the new hood available as a retrofit item for customers currently operating W900Ls with a curved windshield.

Kenworth’s W900L advanced polymer truck hoods are made with METTON® liquid molding resin (LMR) from Metton and are approximately 84 square feet (7.80 m2) in outer surface area. METTON LMR is less dense than other materials, helping Kenworth respond to customer needs for lighter vehicles that offer better fuel economy and greater freight capacity. The new hood provides an 84 lbs. weight savings over the previous spray-up, fiberglass composite hood.

"Kenworth takes pride in innovative truck design that sets us apart from the competition," said Scott Weatherford, Kenworth project engineer, "and so we began prototyping hoods made of METTON LMR in the mid-1990s." Kenworth became more interested several years ago when Metton developed a higher heat-resistant formulation. This allowed Kenworth to run METTON LMR parts through the same high-heat-cure paint lines that are used for its truck cabs. Kenworth's first production use of METTON LMR was with several parts on the T2000 aerodynamic truck, which included a sun visor, chassis fairings (forward, mid and rear), lower bumper, cab side extenders (upper and lower), and a roof fairing.

"In 2000, we began collaborating with Metton and Paramont Mfg LLC (Abingdon, Va.), the manufacturer of the hood," said Weatherford. "We provided design and project management, Metton supplied material and analysis, and Paramont contracted tooling and manufactured the hood. Our customers are enthusiastic about both the hood’s Class-A surface appearance and the ease of opening and closing."

"Of critical importance in developing the application was the challenge to make the LMR hood a drop-in replacement for the previous FRP hood in our manufacturing process," said Weatherford. "The dimensional accuracy and excellent surface finish of the METTON material take away the need for post-assembly operations to fine-tune the fit and prepare the unit for painting. With the new, more accurate hoods, we save 20 to 30 minutes adjusting each hood to its proper position during installation. We spend much less time sanding and repairing paint defects than we did with FRP hoods. As a result, we can also offer the new hood as a retrofit item."

The strength, durability, and flexibility of the liquid molding resin improves the hood’s resistance to star crazing or cracking, which occurs when a tire picks up a rock or other debris and flings it onto the underside of the truck fender. The impact can cause a star-shaped crack to appear on the opposite surface (or show surface) of the fender. Unlike fiberglass, METTON LMR resists star cracking without the need to line the fender with COREMAT fender reinforcement, saving cost and weight.

In addition to impact resistance at normal temperatures, METTON resin parts also offer durability under very cold conditions. Tests have demonstrated its ability to withstand hammer blows at minus 40º F without damage other than scratched paint.

METTON LMR is a family of lightly cross-linked, olefinic thermoset polymers that require only low pressure to a mold cavity. The material is used in commercial vehicle applications and the manufacturing of impact and durability-sensitive products. The hoods are formed in a closed-mold, matched metal die set, through a repeatable process that provides a more consistent thickness than was possible with the previous manually applied FRP materials. The closed-mold process also provides a smoother hood surface, which improves paint appearance.

To mold the one-piece hood, Paramont us

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