Japan's Toho Tenax Co. Ltd. and Kawasaki Heavy Industries Ltd. have developed a carbon fiber reinforced plastic railway carriage component that for the first time replaces steel in coil springs, helping to lightweight rail cars.
Tokyo-based Toho Tenax said Dec. 21 that the CFRP leaf spring can be mass produced for railcar trucks, and is in use in Kawasaki's “new generation” rail truck, its efWING, which it began delivering to customers last year. A railcar truck is carriage and wheels, while car itself is the structure riding on the truck.
Toho Tenax, which is part of the Teijin Group, said it will help establish integrated production from the carbon fiber yarn to the CFRP springs, and that the new system will be marketed globally.
The leaf spring replaces the steel coil springs and side frames in conventional rail car designs, saving about 900 kilograms (1,980 pounds) of weight per railcar and reducing the risk of derailment. Toho Tenax said the part is the first in the world to combine the steel parts into a simplified CFRP solution.
The work with Kawasaki is part of Toho Tenax's strategy to work more with downstream customers to develop CFRP products.
“Teijin Group aims to expand its carbon fiber and composite businesses by increasingly focusing on innovative transportation solutions, a key element focus of our downstream strategy,” said Takashi Yoshino, Teijin's executive officer and president of Toho Tenax.
Kawasaki said the arch of the CFRP part provides better suspension control, stabilizing the force transferred from the wheel to the rail. That results in more protection against derailment and more passenger comfort, the company said.
The efWING won the Good Design Gold Award in 2013 from the Japan Institute of Design Promotion.