Railway Ties Made From 'Polyurethane Wood' Incorporating Bayer MaterialScience Composite System Offer Clear Advantages To Wood
Pittsburgh - It looks like wood and has all the positive attributes of wood, but a new material that incorporates a Baydur composite system from Bayer MaterialScience offers clear advantages to wood for many applications, including railway ties. This application was displayed at Bayer MaterialScience's booth at Composites 2005, Sept. 28-30, 2005, in Columbus, Ohio.
The composite material, Elson Neo Lumber FFU (Fiber Reinforced Foamed Urethane), is reinforced with long glass fibers and produced by Sumika Bayer Urethane Co. Ltd., a subsidiary of Bayer MaterialScience AG. An extremely dimensionally stable composite material, Elson Neo Lumber FFU, unlike natural wood, loses none of its favorable mechanical properties even after long-term service in the open air. The polyurethane-glass fiber composite is also superior to concrete, thanks to its low weight and simple machinability on-site. Furthermore, the material's good resistance to hydrolysis, greases and oils makes the "polyurethane wood" a very reliable material, even when exposed to long-term weathering. In railway tie applications, the material's excellent electrical insulation properties allow the ties to be fitted with heating elements to prevent freezing in winter. In addition, the material is resistant to frost and deicing salt.
Despite its many advantages, the composite has very similar working properties to those of wood. In this case, the ties can be screwed together, sawed and nailed with regular woodworking tools. Each tie, which can be produced in almost any length using the pultrusion process, sports an internal bond even stronger than that of wood.
A recent application is the Zollmat Bridge in Vienna, Austria, which marked the European debut of the material. Polyurethane wood has been used in the Asian market for more than 20 years, so when renovations were proposed for the bridge, OEM Sekisui Chemical, a Japanese company, offered this composite solution.
"Structural improvements to railway tracks typically involve considerable inconvenience and high costs, while repairs on bridges cause even more concerns," explained Harry George, business manager, Specialty RIM Group for Bayer MaterialScience. "Fortunately, Elson Neo Lumber FFU provides a viable and favorable alternative to wood."
In addition to the Zollmat Bridge, Elson Neo Lumber FFU has been used as a replacement for wood in a number of other applications in the Far East, including pools for fish farming, walkways, soil anchors and tunnels. "We expect applications to become increasingly widespread as more manufacturers discover the many benefits of utilizing this composite material," said George.
SOURCE: Bayer MaterialScience LLC