Recycled tires used for rubber railway ties
The North American railway industry replaces approximately 18 to 20 million 8.5 foot long ties annually, with 90 percent of them being made from hardwoods and softwoods that are coated with creosote, a hazardous material. The majority of the remaining 10 percent are made of concrete.
Based in Cazenovia, New York, NP&G Innovations, Inc. has developed the Tire-Tie™, 8.5 foot rubber rail ties that weigh approximately 400 pounds each. These ties are made from the treads of a substantial number of car and truck tires.
“By weight we use 65 to 70 percent of the tire, including the steel,” says Cal Nichols, president and co-owner of NP&G. “We designed it to meet or exceed the current wood tie and concrete tie standards and it’s an environmentally friendly product.
“This avoids the need for ancillary protective treatments like creosote used with traditional wood ties,” he adds. “Creosote has been designated as a restricted use material by the United States EPA.”
The sidewall portion, while it cannot be used in the tie production, can be ground into crumb rubber and sold, which ensures that the entire tire is recycled.
In terms of comparisons, a standard wood tie weighs 250-275 pounds, while a concrete tie is between 800-1,000 pounds.
The firm is planning to start production in the third or fourth quarter of 2007.
The ties, which can be used to replace individual ties or cover complete stretches of track, are being tested on a short line (500 to 600 miles of track) in New York State, where they have been in place for the past three years.
“They have seen about six million metric growth tons and have seen no degradation whatsoever,” says Nichols. “The line is in upstate New York and the ties have experienced all weather conditions.”
In terms of durability, the firm’s current estimate is that they last three to five times longer than standard wood ties.
“It varies according to use,” says Nichols. “In the southern climate, the wood is exposed to termites, other insects, soil conditions, heat and drainage – things that are a big issue to railways and which our product can overcome. Our ties have been designed to meet wood tie standards. Laboratory and field testing of engineering samples have shown that the concept will meet the American Railway Engineering and Maintenance of Way Association guidelines for alternative cross ties.
“They will be more expensive,” he adds, “but we have a premium product. Given the labor and cost savings of our tie, we can present a good case. In renovations to a line, the industry estimate is that a tie of mixed hardwoods is about $40. If you are doing a complete new track, labor per tie is a little bit less. It has been estimated that the labor is about the same cost as the tie. The cost of tie and labor for rubber ties is considerably less over time.”
The major railway companies are following the development of the rubber ties and NP&G has been working with railway personnel at the technical level.
The rubber tie is expected to make a dent in the European market which is split 50/50 in terms of wood and concrete ties.
“Concrete ties are prone to cracks,” says Nichols. “In Europe they place rubber pads between the rail and the concrete ties to deaden noise transmission and vibrations.”
Railway lines span the entire country and since rubber ties are heavy to transport, establishing production facilities across the nation adjacent to tire dump facilities are probable.