Truck tire management is a full-time job. Ensuring that they’re rolling correctly inflated is the best way you can ensure that you’re hitting your tire cost per mile expectations and setting yourself up to reap the retread lifecycle of the casing. It’s a daily battle, but what if it didn’t have to be? What if you didn’t have to worry about inflation at all? What if your tires were ready to roll any time? Those are the types of questions Bridgestone’s air-free commercial truck tire concept raises.
Okay, so those are just a few of the questions that come to mind because I hurled a handful of others at Jon Kimpel, Bridgestone executive director of new mobility solutions engineering, standing in front of the cool concept tire in Bridgestone’s booth at the 2020 TMC Annual Meeting and Exhibition. Here’s what he had to say.
Fleet Equipment (FE): Take me through what we’re looking at here.
Kimpel: This is our air-free commercial tire concept for use in high-speed, long-haul applications. It’s made of three different components. We have the metal wheel, a web structure and then a reinforced tread band on the outside. With a pneumatic tire, especially on the truck side, it could have 120 PSI of air pressure. So, that air pressure does a lot of work. With this concept, what carries a majority of the load is the tread band in addition to the web portion.
FE: The sidewall is unique, obviously the tread on top is familiar. What are the materials that go into the construction here?
Kimpel: To start from the very middle, it’s a steel wheel, much like the steel wheels of today—the only exception is the geometry. It’s a straight, flat surface as opposed to ridges because of the requirements for beads in a pneumatic tire. We don’t have a bead on a non-pneumatic tire.
Then the web itself is a thermoplastic. It has progressed to the point where it’s more advanced in the materials there. They can handle a broader temperature range, as well as the right reinforcements to actually go in and handle this kind of load. Because, we’re looking at a tire that can handle 5,000 lbs. and still go 75 MPH, which is what this tire concept is currently being tested for.
Then the tread itself is common to what we use today, much like the Bridgestone Ecopia tires. And the tread band is reinforced to help carry the load.
FE: Okay. So what is the reality of this technology, and what’s the next step in development of the product?
Kimpel: We’re in the validation of the concept right now. We’ve done testing to realize that we do think it’s viable. Bridgestone tests all of our tires over hundreds of thousands of miles and we’re taking that quality-based approach to make sure we are developing a product that’s safe, durable and meets the expectations for our customer base. As far as timing, it’s years away. It’s not decades away. But again, it needs to go through that validation phase.
FE: Is that just internal validation or do you have this out for pilot trials with customers?
Kimpel: It’s still in internal validation at this point.
FE: So what are you seeing in terms of rolling resistance? How does it compare with a pneumatic tire?
Kimpel: Considering that a pneumatic tire with air pressure does a tremendous amount of work, we had to be very selective in terms of the materials that we use. They need to be very, very efficient. And so, as the efficiency goes with the tires, materials that handle that kind of load and that kind of speed would also result into an acceptable rolling resistance as well.
FE: What about the impact on ride quality?
Kimpel: Consider that this is not a solid tire. It’s an airless tire. So in some of the testing, we’ve seen that the center webbing construction of the tire compresses as the vehicle goes down the road, which creates a good tread footprint for road contact. Therefore, from a ride quality standpoint, we believe we can tune the design to deliver a ride consistent with what commercial fleets require and are accustomed to with pneumatic tires.
FE: What about durability and lifecycle expectations?
Kimpel: This is where the real benefit of air free tires comes in—when you consider both durability and total cost of ownership. If we take out the variable of air—the air pressure maintenance, the durability issues and related considerations—now you have a strong product making mobility even more efficient and safe.