Has Wheel Torque Solutions found a solution to wheel-offs?
April 1, 2010
TAMPA, Fla. - A series of four companies have joined together under the banner of Wheel Torque Solutions to unveil a wheel system that promises to maintain higher clamp loads and eliminate most of the...
TAMPA, Fla. –A series of four companies have joined together under the banner of Wheel Torque Solutions to unveil a wheel system that promises to maintain higher clamp loads and eliminate most of the traditional causes of wheel losses. And they have already found a fan in Rolf VanderZwaag, who oversees technical issues for the Ontario Trucking Association.
Chicago Pneumatic, Alcoa, ITW CIP, and B&D Cold Heading unveiled the system -a combination of components and tools -during recent meetings of the Technology and Maintenance Council. Pac-Sleeve laminated lock nuts are combined with strengthened B&D bolts and Alcoa aluminum wheels that are thicker than usual where the fasteners are applied. Related tools come in the form of sanders and polishers to properly clean mounting faces, metal sleeves to guide the wheels into position, specially designed nut-runners and impact wrenches. In designing a system for severe applications, the suppliers have addressed all the root causes of wheel losses, said VanderZwaag, who was instrumental in creating the program used to train Ontario wheel installers.
“The key to strengthening the clamp force is maximizing the preload and grip length without comprising the structural integrity of the components,” explained Ross Hill, business development manager at ITW CIP. “Wheel Torque Solutions accomplishes this through the use of industry-leading components that have been tested to achieve maximum clamp force at torques greater than 600 ft.-lb.”
The Pac-Sleeve nuts incorporate a stack of five internal washers that will deflect 30 thousandths of an inch as they are pulled together, compared to a solid fastener that will deflect a maximum of 19 thousandths of an inch when the wheel components are tightened with 60,000 pounds of clamping force. The extra deflection is designed to compensate for the flexing, temperature changes, expansion and contraction that can take place during normal operation.
There are wide variations in the quality of nuts and bolts in the marketplace, and some of the poorest offerings even deliver less than the 30,000 pounds of clamping force needed to hold a wheel in place, VanderZwaag added. “It’s the clamp force that holds the wheel on. Not the torque.”
After the mounting surfaces are properly cleaned, a half-inch driver is used to seat two or three long metal sleeves onto the wheel bolts. The wheels are slipped over the sleeves that ensure everything is seated in the proper position, nuts are lubricated and spun onto the bolts, and then everything is tightened with a Blue Tork electric nut runner using about 600 ft.-lb. of torque. The electronic tools scan and confirm the exacting torque values of each installation. While mounting surfaces are supposed to be clean, it can be difficult to get into the small areas on the face of a brake drum, VanderZwaag adds, referring to the importance of the cleaning tools. “You’re now in there getting that as clean as you possibly can.”
The system has been in development for more than a year, with an unnamed fleet that had faced a catastrophic wheel loss.
The suppliers suggest that their solution even eliminates the traditionally recommended practice of rechecking torques after newly installed wheels travel about 160 km.
That can be particularly important. Even though the industry’s current procedures require drivers to check the condition of fasteners on the road, there are no clear instructions on what drivers should do if certain conditions are found. And how many of them have a torque wrench at the ready?
“If you assemble this thing properly, you don’t have to check it,” VanderZwaag says. “You’re absolutely covering every step.”