Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 1

Wood Plastic Composite Decking Manufacturing Process

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 2

What are WoodWhat are Wood--Plastic Composites (WPC)?Plastic Composites (WPC)?

Combination of Wood-Plastic

Thermoplastic- HDPE, LDPE, PP, PVC

Wood Flour- 20 to 60 mesh- Pine, Oak, Maple

Lubricants, Pigments, Coupling agents, other additives

Technology

Extrusion, Injection or Compression molding

Pre-Compounding

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 3

How are How are WPCsWPCs manufactured?manufactured?

Logs, Chips, Shavings, etc.

Hammermill

Wood Flour

Blended

Extruded

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 4

General Manufacturing FlowGeneral Manufacturing Flow

Resin Silo

Wood Flour SiloCompounder or Blender Extruder Die Calibrator Spray Cooling

Cut-off SawEmbossing

Brushing

PullerStacker

Chiller

Extruding System

Resin Silo

Wood Flour SiloCompounder or Blender Extruder Die Calibrator Spray Cooling

Cut-off SawEmbossing

Brushing

PullerStacker

Chiller

Extruding System

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 5

Dried, Compounded, ExtrudedDried, Compounded, ExtrudedPre-dry Wood Flour (<2%)Dry Blend ComponentsTwin-Screw Extruder

Compounding

Source: Milacron Inc.

Vent

Compression

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 6

Typical Extrusion LineTypical Extrusion LineWood Materials & Engineering LaboratoryWSU, Pullman, WA

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 7

flexible manufacturingdoes not cater only to economies of

scalelow capital investment

Courtesy of WMEL, Washington State University, www.wmel.wsu.edu 8

www.wpcinfo.orgMaintained by Wood Materials and Engineering Laboratory (www.wmel.wsu.edu) at Washington State University