As mining equipment and OTR tires get bigger, handling giant OTR tires is becoming more difficult.
And by big, we mean big. Bridgestone Corp.'s 59/80R63 V-Steel E-Lug S mining tire stands 13 feet tall, weighs more than five metric tons, and is designed for dump trucks that can carry loads of 380 to 400 tons. Michelin North America Inc.'s 63-inch tire shares the V-Steel's dimensions and targets 360-ton haul trucks.
Goodyear Tire & Rubber Co.'s largest offering, the 44/95R57 RL-4B Haulage, stands nearly 12 feet tall with an overall diameter of 140.5 inches.
Moving such gargantuan products by sling or chain doesn't cut it, say tire service truck and equipment manufacturers. More commercial tire dealers are using tire hands, or manipulators, to do the job -- with positive results, including greater ease-of-change, quickness and safety.
Many large machines have fenders and other obstacles that get in the way of applying slings, says Jim Darr, product specialist for Iowa Mold Tooling Co. "With tire hands, you come in from the side" and grab the tire. "Also, if you're using slings, you're working in more confined areas."
Lending a hand
Safety is the driving factor behind the use of tire manipulators, says Tom Formanek, sales manager for Stellar Industries Inc. "Owners are saying, 'I need to take care of my employees. We need to have the right equipment.' A lot of companies won't let you service their tires if you don't have the correct equipment."
Finding a tire hand for OTR applications is relatively simple, Formanek says. "Look for one that will meet your needs, capacity-wise." Also look for features like flange rings and rotating pads that will make operation easier.
Remote operation capabilities are a must, according to Formanek. In addition to keeping service truck operators out of harm's way, remote controls "give them the ability to watch what the machine is doing."
Gripping OTR tires themselves requires a skilled hand. "You have to apply enough pressure, but you don't want to damage the tire," says Formanek. "We program our equipment to set adequate pressures, but a lot is based on experience. Foam-filled tires, for instance, are harder to squeeze.
"Plus, if you squeeze (a tire) too much, you're distorting its shape and making it harder to mount. It comes down to a judgement call by the operator."
The right truck
Like tire hands, choosing the right OTR service truck also is application-specific. "Mini-booms are becoming quite popular," says Sam Nash, general manager for Piedmont Service Trucks. "There are many more small OTR applications than large ones," including "backhoes, scrapers and buckets."
Mini-booms are more versatile, he adds, and economical, pricing out between $65,000 and $85,000 on average.
Some operations, like large construction companies, require mid-size OTR service trucks, "which are mini-booms that have been updated," says Formanek. "It's not a full-blown, dedicated OTR truck, but it gives you flexibility." Mid-size units cost between $80,000 and $90,000 each.
Single-axle trucks are the next step up. "If you don't have to do a lot of hauling, it's a beautiful truck," says Formanek. However, single-axle units -- which cost around $130,000 -- are limited by gross vehicle weight (GVW). The GVW of single-axle service trucks tops out at 33,000 pounds, he says. "Beyond that, you have to pay a 12% Federal Excise Tax.
"Do you really need the legal hauling capacity? Is hauling the main function? A lot of states are cracking down on weight. It's a judgement call." As a compromise, some of Stellar's customers use tandem-axle trucks with smaller-capacity cranes.
However, some customers -- particularly large mining operations -- can be adequately serviced only with dedicated, tandem-axle trucks that boast "a large crane, tire hand and air compressor, plus a flatbed body so they can haul tires and carry tools" from site to shop.
Again, GVW is a consideration, says Formanek. The GVW of a tandem-axle chassis is 58,000 to 60,000 pounds. Tandem-axle OTR service trucks generally cost nearly $200,000 per unit.
Other considerations
Servicing OTR tire customers goes beyond having the right truck and equipment. Goodyear Tire & Rubber Co. tells its OTR customers to look for the following when evaluating potential commercial tire dealers:
* "Cost-per-hour or cost-per-mile are more important measurements than initial price."
* Service, including "having the right tire when it is needed, along with tire surveys, training and tire records." Surveys should highlight inflation maintenance, wear rates, tire damage, and "help predict the timing of future tire needs."
"Quality products and service are what a contractor should look for first in an OTR tire dealer," says Goodyear.
OTR tire segment just keeps growing -- Several tiremakers offer new products
Several companies have rolled out new OTR tires during the past year.
Alliance Tire Co.'s new 600/50R22.5 A-390 radial flotation tire is designed for small earth-moving machines like loaders, excavators and dampers, and can run up to 75 mph on the road.
Bridgestone/Firestone Off-Road Tire Co. (BFOR) recently introduced its V-Steel N-Traction. It has a deep L4 tread for cut protection.
The new Bridgestone VLT V-Steel L-Traction is designed for articulated dump trucks. BFOR's VLTS V-Steel L-Traction S contains tread compounds specifically designed for loaders and earthmovers, while the Bridgestone VSDT V-Steel Super Deep Traction targets moderate to severe conditions.
Continental Tire North America Inc.'s radial OTR line, which was unveiled earlier this year, includes five tire models with multiple steel tread belts, hazard scuff bars, square shoulders and other features.
Goodyear Tire & Rubber Co. continues to add wide-based, 65-series radial tires to its OTR line-up. "There are significant benefits to switching to 65-series tires," says Tom Walker, general manager for Goodyear OTR tires worldwide. They include increased traction, tread life and rider comfort. "We now have more than 40 sizes of 65-series tires for wheel loaders and articulated dump trucks."
Kenda USA has a new OTR tire, the Rock Grip, which targets skid steer machines.
Michelin Earthmover Tires' new XsnoPlus 170E targets mobile cranes and logging machines that work in snow or ice; it is available in 14.00R24 and 14.00R25 sizes. The Michelin 18.00R33 X-Haul is designed for severe operating conditions and contains a reinforced sidewall.
Earlier this year, Michelin debuted its 59/80R63 XDR tire for ultra-class haul trucks at large surface mines; the tire, which was co-engineered with Caterpillar, can carry more than 229,000 pounds.
Titan Tire Corp.'s LSW 455-610 tire targets trenchers that place cable lines deep in the ground. Titan also has rolled out the Lift Rigger II telehandler tire and the H/E Hulk Eater skid steer tire for use in steel mills, gravel pits and other extreme situations; both are available in three sizes. Titan's 12 PR and 16 PR Supper Rigger tires have three new sizes, as well.
Yokohama Tire Corp's new Y524 L5 is designed for loaders and contains a 13% thicker inner liner. The company's Y69U has special steel reinforcements and targets underground mine applications. And its RB31 tire boasts zigzag grooves, a flat-based hexagonal bead and other features.
