Belt design combats high temperatures and tension

July 2014 - When a production line stops because the material handling system fails, the loss of productivity and dollars accumulates quickly.

Cambridge Engineered Solutions is more than familiar with the ins and outs of conveyor belt systems after 103 years in the business. “Extreme heat—high temperatures over 1,700 degrees—causes metal belts to stretch, requiring repairs that halt production,” says Cory Bloodsworth (pitcured at right), market sales director for high-temperature industry at the Cambridge, Maryland-based company. 

The solution to heat-induced downtime is the Knuckleback belt, which focuses on high heat applications such as sintering, brazing, annealing and hardening, among other processes. “The parts produced in these applications are used in everything from the cars and trucks we drive to the appliances in our homes and the motorized toys our children play with,” Bloodsworth says.

The use of stainless steel allows Cambridge’s new conveyor system to compete directly against other materials, such as “more exotic nickel-based alloys, [but] at a much lower upfront cost,” Bloodsworth says. The Knuckleback’s design features a reinforced, reversed weld of the joint (the knuckle) between the rod with each flat spiral wire end (back) to the preceding joint. According to Cambridge, the weld is designed to move the tension away from the weld point by knuckling the spiral wire prior to welding and allowing it to withstand wear longer.

Instead of stretching when immersed in a high-temperature environment, as is the case with traditional mesh conveyor belt designs, the Knuckleback flat surface has an extended, stronger spiral design that reduces stretch to minimize camber and resist slag build-up. 

Customer feedback

“We designed our Knuckleback belt based on customer feedback,” Bloodsworth says. “The reduced stretch helps keep camber to a minimum: If we reduce the amount of stretch on the spiral wires, the cross members have less room to camber.”

The spiral sections of the Knuckleback increases resistance against stretch by giving the belt a thinner profile versus common high-temperature mesh belts. One particular example of the design’s superiority is the annual savings and reduction in downtime for belt maintenance the customer should expect to experience, including reducing the need for replacement.

After receiving promising results during testing, the company installed a dozen Knuckleback systems last year. Inquiries continue to come in. “We are always looking for ways to increase production for our customers,” Bloodsworth says. “We evaluate our products from a total cost of ownership standpoint, not just longevity. We focus on the issues that cause belt failure and downtime for production and work to eliminate these issues, allowing for the highest possible return on investment.” MM