WILMINGTON, N.C. (Sept. 25, 1:45 p.m. EDT) — Wood fibers have swept into the extrusion world. Next up: injection molding, at K 2001.
Wilmington Machinery Inc. will debut its wood-filled injection molding technology at K 2001 (Hall 3, Stand E 73-1). The Wilmington-based company said it successfully has molded parts from 30 percent wood-filled polypropylene on a specially designed, 375-ton, two-stage injection press.
President Russell La Belle thinks it may be the first such injection molding of wood-filled plastics.
The material must be carefully dried, then melted in a low-shear-sensitive apparatus that extensively mixes and cools the melt. The Wilmington press then uses high pressure to fill the parts quickly — big shots of plastic from 3-5 pounds — in a fraction of a second.
The company said wood-molded parts are stiffer than nonfilled parts, run on much shorter cycle times and can reduce part costs. Potential applications include seat and back pieces for upholstered furniture, decking, marine products and materials-handling items such as pallets and bins.
North Wood Plastics Inc. of Sheboygan, Wis., supplied the PP/pine fill material. Stabilizers, lubricants and foaming agents came from Reedy International Corp. of Keyport, N.J. Wilmington Machinery had technical help from Bill Crostic of Onaga Composites in Sugar Hill, Ga.
Also at the K show, Wilmington will debut a continuous rotary blow molding machine for making large parts such as toys, recreational products and materials-handling products. Also new is a vertical series of rotary blow molders with single, dual or triple parisons.
In structural foam, the company also will introduce a hybrid machine that reduces energy consumption, a new modular manifold for fast setup and “onboard control” nozzles that handle as many as 48 filling sequences.