Kumho Tire’s U.S. tech middle hub of innovation

Kumho Tire’s U.S. tech middle hub of innovation

“Over here is where we mix batches,” Mr. Bradnick said. “We don’t have anything to mix today. Plus, if we were mixing, we wouldn’t be able to hear each other.”

Like Mr. Covey, Mr. Bradnick is tasked with ensuring that the tires designed and developed by the team do exactly what they are supposed to do. And the way the Kumho team sees it, its developments are in good hands. Mr. Bradnick brings more than 45 years of rubber industry experience to his position — he started out in the custom mixing space before joining Kumho in 2001 — and his sense of humor helps to make daunting challenges seem surmountable.

Armed with a range of equipment, both traditional and modern, Mr. Bradnick conducts a variety of tests from viscosity and tensile testing to compound analysis. His goal is to help build a more accurate vision of how a tire would perform on the roadways by better identifying characteristics such as grip, braking and rolling resistance.

“On one end of the spectrum is, like, a super ball,” Mr. Bradnick said. “It has great rolling resistance, but the braking would be terrible.”

Ensuring that tires perform optimally is tricky, particularly as the demands of electric vehicles change the game and redefine exactly what tires can and should be doing.

EVs simply demand more from tires. They have much higher torque, which changes the requirements for grip. And, given the weight of EVs, tires need to be much more robust, able to carry the loads of the heavy battery packs.

Sprinkle in expectations for more sustainable materials and end products, and you’re facing a tough challenge.

“What a lot of people don’t understand is that the grip that the tire has and the wear—and then we want rolling resistance now to be environmentally friendly and use less energy—they are diametrically opposed,” Mr. Dailey said. “We are literally trying to bend the rules of Mother Nature a little bit.”

Joe Lanzarotta is a senior compound engineer who works closely with Mr. Dailey, and has since the duo designed tires together at General Tire decades ago. And with more than 40 years of experience, Mr. Lanzarotta has seen the industry transition. Today, he said, tire makers again are searching for that next big breakthrough, the 21st century equivalent of silica.

“Silica was huge,” Mr. Lanzarotta said. “Silica really took tires to the next level, now it’s really a challenge of what’s next? What can we find that will make the next quantum leap?”

In the materials realm, a number of new and promising options are beginning to emerge, particularly with renewable and sustainable resource options. But the industry still is learning how those new materials will change the tire’s makeup and performance.

“We have 100-150 years of tread patterns, so a lot of them are beginning to look quite similar,” Mr. Lanzarotta said. “It’s what is being put into those tires that is really changing.”

The right recipe
But it’s more than just what you bake into the tire compound that matters. How you make that tire, matters, too. And those subtle differences in compounding and manufacturing are what set tire makers apart, according to Dailey.

“You take the same materials—because it’s like everybody in the tire industry has it available, right? So, the question is: How do you put those together? What method do you use?” Dailey said. “I equate it to my grandmother’s chicken dumplings vs. my mother’s. I love my grandmother’s, but how she does it a certain way, seems to be better than mom’s, but they are both good.

“So it’s the method and the material selection, when you add those things together, how you do it and the equipment you use in the manufacturing process—all of that has an impact on tire performance.”

And this is where Bradnick comes in. He leads the charge in helping to perfect the best tire recipe. At times, that’s something easier said than done, he noted, reiterating Dailey’s point that intricacies in mixing and manufacturing can change a product.

He pointed to a range of rubber samples he has on hand to help prove his point. Each sample, simple rectangular rubber mats marked to designate their testing order, look almost exactly alike. But their feel—their properties—are quite different.

“These are all the same recipes — same ingredients — just different mixing temperatures, parameters (or) order of addition to see if we could get the dispersion of the silica really dialed in” Bradnick said. “So it’s not just about ingredients. You have functional polymer, you have silane, you have silica, and they all work together.”

Sometimes, when it comes to the material compounds, the best ideas and hunches work exactly as planned, paving the way for a better tire. Other times, the materials don’t blend quite as you hope.

But that’s all part of the experience, according to Bradnick.

“We make our share of batches that come out of (the mixer) as powder,” Bradnick said with a smile. “We have a Shop-Vac just for that.”

“I’ve had that happen a few times,” Dailey added with a laugh. “I gave him a batch one time and told him, ‘Hey, this is going to work great!’ Later, he came out to my desk and goes, ‘man your broom.’ “

No bad days
Tire compounds are just part of the equation. The tread design matters, too.

Finite element analysis helps to refine many of these designs and saves a lot of time and money on the prototyping end. But the only way to truly see how a new tire manages roadways is by taking it to the pavement.

Before the KATC does that, it turns to Don Heath, the tech center’s resident tire carver. Using a printed overlay of the tread design as a guide, Mr. Heath carefully makes each tread cut by hand, using his specialized tooling. It’s a time-intensive task that requires both precision and patience.

And Mr. Heath has it down to a science. He’s been carving tread patterns into tires for more than 40 years, having honed the craft as a General Tire employee before joining the Kumho team.

With that kind of experience, he said, you can bet each cut is accurate.

“I don’t have bad days,” Mr. Heath said, before jokingly adding, “only when the Browns lose. Those are bad Mondays.”

“Yeah, we just don’t carve anything from October to January,” NVH Manager Ken Albers replied with a smile.

Jokes aside, Heath’s work is incredibly accurate — and incredibly valuable. In a matter of weeks, he can add a tread pattern to a set of test tires, and that’s a big savings for the company, which doesn’t have to build expensive molds for a design that may not work.

“You can do a set of these in about 10 working days,” Mr. Heath said. “In a month, month and a half, you can get four sets done instead of the cost of a mold. And, if all else fails, you can go back to start over again if these don’t work out.”

Pitch perfect
For tires to work exactly right, they have to meet all our senses. They have to feel right, handle right, perform optimally when most needed — and in any road condition.

They also have to sound just right. As an NVH specialist with OEM experience, Mr. Albers is tasked with ensuring they do. It’s a job that is becoming even more critical with the rise of EVs.

“Noise is very important with electric vehicles because you don’t have a combustion engine that masks a lot of the other noise inside the vehicle,”Mr. Albers said. “So it is very critical to get noise down to a level where you don’t really notice it.”

And it’s in the soundproof workspace of the Akron-area facility that Mr. Albers works to find that perfect sound.

Often, that means going through recordings of tires rolling along road surfaces of varying kinds, pinpointing sounds and determining how to refine the noise to something more suitable for the driver and the specific vehicle, in the case of OE fitments.

Mr. Albers settles in behind the laptop and with a few mouse clicks pulls the visuals of an audio recording onto the screen. He presses play, unlocks the audio file and the oversized cursor on the screen scrolls left to right over the unique, jagged audio rendering as a low, steady hum fills the room.

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