Fiber composites, large pipes drive extrusion sector
January 1, 2006
Developments in materials, products, and equipment, coupled with the benefits of plastics in cost, installation ease, and longevity over materials such as steel and concrete, are creating new opportunities.
New opportunities for pipe and profile extrusion reside in markets like building and construction, infrastructure repair, and home improvement.
Demand for pipe and profiles is growing worldwide, especially in China, Eastern Europe, and North America. China and Eastern Europe have undertaken massive construction projects that are driving orders for pipe and profiles. Millions of tonnes of polyvinyl chloride (PVC), polyethylene (PE), and polypropylene (PP) are being specified for products ranging from window lineals to pressure pipe and drainage pipe.
Government regulations can also play a role. China, for example, has mandated that 30% of window frames in new construction be fabricated of PVC by 2005 to increase energy efficiency.
China is not only a huge consumer of extruded profiles, but a major producer as well. One company alone, Dalian Shide Plastic Industry (Dalian, China), has purchased more than 400 high-tech extrusion lines from two German companies to produce window lineals.
Back in the U.S.
Extruders in China and other parts of Asia also seek to be exporters. An indication of how advanced some sectors of the Chinese extrusion market are becoming was seen recently when the American Architectural Manufacturers Assn. certified one processor''s window and door systems for sale in the U.S. Companies can export such products to the U.S. without certification, but local building codes and specifications usually require it.
In the U.S., markets like large-diameter pipe, window lineals, fencing, and natural-fiber composite profiles (which include decking) are growing annually at or near double-digit rates. Vinyl siding is a high-volume but mature business, and there is overcapacity in small-diameter PE pipe, a result of slack demand for telecom conduit.
Most large-diameter PE pipe is up to 24 inches (610 mm) in diameter. A few manufacturers produce 48- and 63-inch-diameter (1219- and 1600-mm) pipe with walls 3.5 inches (89 mm) thick. Factors influencing the market include growing use of such pipe in municipal and industrial pressure systems due to PE pipe''s ability to be butt-fuse welded for leak-proof seals. The U.S. is currently losing 2.5 billion gal (9.46 billion liters) of treated drinking water daily due to broken pipelines. Plastic pipe is also easier to transport and install than steel, clay, or concrete.
Large-diameter pipe is not limited to the U.S. Norwegian extruder Pipelife (Stathelle) ordered a line that can produce high-density PE pipe 2m (6.5 ft) in diameter with wall thickness to 135 mm (5.3 inches). Products will be used to replace concrete and steel pipes in drainage and sea floor applications.
The biggest factor affecting U.S. pipe and profile demand is building and construction. Major products include vinyl siding, windows, and decking.
Margins squeezed
Price pressure is intense in vinyl siding. Margins are so tight that producer consolidation will reshape the industry.
Nevertheless, there is R&D that could yield important new products in 18 months. One such development is natural-fiber composite siding. This is a profile extruded with wood fiber and PE, PP, or PVC. Among the benefits: Composite siding is four times thicker than vinyl and provides better insulation; and it weighs less than fiber cement panels and so would be easier to handle and install.
PVC and PE are the chief resins used in profile extrusion. Work is under way, though, to increase the use of polypropylene. PP is already an option in some parts of Western Europe, including Scandinavia, primarily as a PVC alternative. Efforts are focusing on developing engineered PP grades that outperform PVC in heat-deflection temperature and rival the impact properties of PE. Europe leads the world in this regard. One concern is whether propylene monomer pricing will continue to rise, and if there is enough PP capacity for demand.
If PP gains greater use in pipe, extruders will need to reassess their equipment. It is impractical to run PP and PE in a smooth-bore extruder with the same screw since PP output and melt temperature would be severely affected. Grooved-feed extruders, however, permit one screw to be used for both resins with minimal affect on PP throughput. Processors who run both materials might thus consider switching to grooved-feed extruders.
Kurt Waldhauer, president/CEO, American Maplan [email protected]
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