For most of the world, static buildup is an invisible phenomenon. But for those who work anywhere a forklift fleet is running on non-marking tires, the potential for static shocks and sparks is an ever-present hazard.
In the previous article of the series, we explored what is static buildup and the causes of this phenomenon on non-marking tires. The non-marking characteristic of the tire rubber is the result of using silica instead of the traditional carbon black. Carbon black is a highly conductive material, and it’s this ingredient in the rubber recipe that allows tires to ground the vehicles they’re on. Non-marking tires don’t have this anti-static property since silica is acting as an insulator. With non-marking tires, the static charge in the forklift builds up to potentially hazardous levels – enough to spark up a fire in the truck, to wipe out electronic circuits, or to knock down a person who inadvertently touches the equipment.
The industry has tried makeshift methods of dealing with problematic static. Some forklift operators will attempt to ground the vehicle by raising the forks or attachment, and slamming it onto the floor. This not only damages the floor and equipment, it generally doesn’t work. The frame and equipment attached to the forklift are insulated from the drivetrain components that actually accumulate the charge. Grounding the attachment does generally not ground the accumulated electricity, no matter how hard you hit it.
More commonly, users will attach chains or grounding straps under the truck. The idea is to allow the electricity to dissipate on the floor as the truck operates. But again, their effectiveness is limited. Drivetrains are still insulated from the frame by rubber mounts and bushings. Meantime, the straps and chains tend to gather dust and debris over time that gradually insulates them from the ground. They may also wear down or break off. Then more operating costs are incurred for maintenance staff to inspect and replace them.
Solving it at the source
Ultimately, the problem originates with using tires that fail to ground the vehicle and, up to recently, tire manufacturers have not offered a solution. Specialized anti-static tires are available for certain applications, but there have been no non-marking anti-static (NMAS) tires available until just this year.
We began investigating the notion of a NMAS tire three years ago. In discussion with a customer experiencing major challenges with static build-up, our team was determined to come up with a real solution to the problem at ground zero: “Where the rubber meets the floor.”
But the development process actually began with research into an entirely different problem in a paper mill. The customer was looking for a new press-on tire that would simply last longer. Non‑marking tires, while more costly than conventional black tires, typically have a much shorter lifespan than standard black solid rubber tires. Relatively poor thermal properties also make them more prone to premature failure. By no coincidence, these relative shortcomings in heat management and wear life are both the result of removing carbon black from the rubber mix.
“One more thing…”
Our Camso engineers began reworking their tire design and ran live tests with customers. The initial results were successful. New rubber compounds and performance engineering led to a non-marking tire that’s 63% more thermally efficient and lasts 51% longer than the Magnum NM SM. But then the customer requested “just one more thing.” Could Camso also turn the new non-marking tire into an anti-static tire?
This was no simple challenge. Adding some kind of pathway for electrical conductivity in a non-marking tire was just the first step.
The engineering and product line teams field-tested different prototypes. The final design resembles other non-marking tires, but a telltale dot on the face of the tread shows where a carbon black channel had been integrated through the tire steel band. The tire provides a ground for the forklift when the black dot acts as a “plug” and makes contact with the floor on every rotation.
We formally announced production of the new model tire, dubbed the Solideal PON 775 NMAS, and inventory made its way into the distribution network. Darren Stratton, Product Management Director - Material Handling claims the PON 775 NMAS is a true breakthrough in tire design. “It’s not only the first non-marking anti-static tire, it will also outlast any other non-marking tire. It resists chunking and cutting, resists abrasion, and it virtually eliminates the safety hazards and downtimes of static build-up.”
Even better, forklift operators who have tested out the PON 775 NMAS report that they’re very happy with the comfort and ride quality of the tires.
“We couldn’t be more proud of this R&D effort,” Stratton continues. “Customers who use non-marking tires on high intensity applications tend to have the most intensive material handling jobs: larger trucks, heavy loads, high speed runs, rapid maneuvering. Now they are finally getting an extreme performance tire that checks off all the boxes and provides them with the lowest operation cost solution possible for their applications.”