GREENVILLE, S.C. – Michelin has enhanced its truck tire manufacturing practices with new technologies and design processes collectively known as Michelin Durable Technologies (MDT).
One element of MDT is Michelin’s Infini-Coil Technology, a stabilizing belt that runs through the tire to optimize wear and handling. It was initially developed for the X One super single, but will now be incorporated into traditional tires.
Michelin’s Michael Burroughes recently told the trade press Infini-Coil will enable trucks to carry heavier loads with fewer or smaller tires. The Infini-Coil cable is about a quarter-mile long and provides improved driver comfort, an optimal footprint and excellent traction, Burroughes said.
Another component of MDT is a new self-regenerating tread that offers solid grip even after the tire tread is two-thirds worn. Raindrop-shaped grooves have been added near the bottom of the tread so when the tire nears what would normally be the final stages of its life, the groove emerges and it can still provide traction allowing the driver to keep the tire on the vehicle longer. The new hidden groove (comprised of raindrop sipes) exposes itself as the tread wears down, and allows the tire to regain up to 30% of its grip when it would normally be nearing the end of its useful life, Burroughes explained. Essentially, the more a tire travel, the more the tread regenerates itself.
With the new technology, “It’s okay to leave the drive tire on beyond 8/32″,” Burroughes said. “We have to convince drivers that at 6/32″ the tire still has sufficient traction to get through heavy rain and snow.”
The technology is being rolled out on Michelin’s XDA5, which will last up to 30% longer than conventional radial drive tires, the company announced. MDT also involves the use of new double wave matrix sipes that make the tread block more rigid, extending tire life. The sipes feature biting lateral edges that lock together to resist horizontal and vertical stresses.
“We have not compromised traction while adding a significant amount of rubber,” Burroughes insisted. This was proven to editors at Michelin’s Laurens Proving Grounds in South Carolina. Driving at high speeds through corners with standing water, it was impossible to detect any difference in traction between the traditional Michelin tires and the new tread designs – despite the addition of more rubber on the tread.
MDT also extends to Michelin’s retreading operations with the Michelin XDA Hypersipe Retread.
Like Michelin’s self-regenerating tread, the Hypersipe Retread also features sipes molded into the bottom of the tread that appear as the tire wears. The hidden sipes appear at about half tread depth and last to the last 1/32″ of usable tread. This allows the retread to be left on the vehicle longer.
“The Michelin Hypersipe maximizes the potential of pre-cure retreading,” said John Melson, research director for truck tires with Michelin. “The underside of the tread package had been a forgotten frontier for innovation. Now it’s delivering a real performance benefit that helps maintain the traction of the retread consistently over its entire life cycle.”Michelin is investing $500 million into developing MDT and bringing its assembly plants up to speed. By 2011, the technology will be deployed on most of Michelin’s truck tire line.