Synthetic sleeper manufacturer, Sekisui Chemical Co., Ltd. has brought a sleeper recently extracted from service after 30 years to AusRAIL to show visitors how well the company’s polymer technology has held up.
As rail networks have grown in Australia and New Zealand, the sector has become more focused on not only the capital cost, but also the ongoing cost of maintaining its fixed assets.
This is the trend targeted by Sekisui with its Fiber reinforced Foamed Urethane (FFU) sleeper. The company’s marketing manager for Asia Pacific and the Americas Masaki Hayashi says the sleepers are workable like wood, but last signifi cantly longer.
“The difference between timber and FFU is that FFU has longevity,” Hayashi said. “FFU doesn’t rot like timber, and it
comes with uniform quality. When you work with timber, it’s very diffi cult to obtain uniform quality over a large batch.”
A follow-up survey of FFU synthetic sleepers after 30 years in service, conducted in 2011 by Railway Technical Research Institute (Japan), suggested the expected life of an FFU sleeper is around 50 years.
Sekisui is showing off one example of an FFU sleeper with 30 years of service logged at AusRAIL PLUS. Next year the company plans to pluck another from the field, for testing after 40 years of service.
“While timber might last that long under specific circumstances, it will depend a lot on the environment and the usage,” Hayashi said.
The primary benefit of this longevity is the elimination of costs associated with reinstalling timber sleepers over the long term.
“Installation costs including labour, track equipment and safety measures costs are generally higher than material costs, so with a lifecycle cost of 50 years without replacement, FFU works out much better than natural timber in many applications,” Hayashi explains. “A natural not protected timber sleeper in some environments may have to be replaced up to seven times during the lifetime of a FFU sleeper.”
The core design feature of an FFU sleeper is its collection of continuous glass fi bres which run from one end to another. These fi bres reinforce the thermosetting resin foam comprised of rigid urethane resin, which is poured over the glass fibres and then sets during the manufacturing process.
The benefit of using FFU is to enjoy both the features of natural wooden sleepers and those of plastics. The FFU sleepers are a similar weight to natural lumber. Bending strength is stronger than natural lumber, and maintains this strength for a long period FFU manufacturing process means sleepers can be fabricated to a specific height, width, and length.
Visit Sekisui at AusRAIL PLUS at Delkor Rail’s stand, Stand 190.
Contact: contact@sekisui-rail.com
Web: www.sekisui-rail.com