COLCHESTER, Vt.—Nokian Tyres P.L.C. has developed a heavy-duty light-truck tire line, dubbed Rockproof, that it is targeting the professional off-road market.
Scheduled to debut in North America in 2017 in 13 sizes, the Nokian Rockproof offers performance in quarries, forests and mining areas, the company said. The size range will encompass rim diameters from 16 to 20 inches.
Developed in cooperation with Nokian Heavy Tyres division, the tires feature a cut-resistant Rockproof Hybrid tread compound, an aggressive tread pattern for improved resistance in rough off-road conditions and aramid-reinforced sidewalls. The tire combines the special durability of heavy machine tires with the comfort of passenger tires, Nokian said.
To gain real-world feedback, Nokian asked Tom Brain of Dyer Logging Co. Ltd. in Sayward, British Columbia, to use Rockproof tires on his Ford F-350 4x4 for his work in the forestry logging sites of Vancouver Island, where the roads consist mostly of shot rock.
“Nokian Rockproof tires have outlasted all the other brands we've had on our truck,” Brain told Nokian. “We've put on roughly 31,000 miles and more than half of that is on gravel. What we found is that these tires have stood up better than anything we've had on the last two trucks, by far.”
The optimized tread block support provides more precise handling and stability, Nokian said, while two different side angles and the staggered support on the block sides ensure that the tire's tread blocks remain firm and that the groove bottoms will not be damaged during rougher driving. The reinforced upper part of the sidewall provides additional protection against puncture and cut damage caused by sharp rocks, the company said.
The tire also features stone ejectors at the groove bottoms to prevent sharp and jagged stones from attaching to the tread surface and penetrating the tire structure. The stone ejectors improve the tire's service life and offer additional protection by preventing tire body damage, especially on uneven terrain, Nokian said.
The tire's sidewall structure contains strong aramid fiber to reinforce the sidewall and resist impacts and cuts.
“Off-road driving and the toughest professional use require extreme durability from tires, and puncture protection in particular,” said Olli Seppala, product development manager for Nokian Tyres.
“Under these conditions, tires may sometimes have unpleasantly short service lives. Accidental damage causes a lot of additional costs and tire changes result in additional work. The tire has excellent cut resistance due to the tread compound that was developed for use in mines.
“This product has been developed for improving the efficiency of demanding professional use.”