Advancements in tire design are about more than making a better tire. On a local level, they are about helping fleets lower operational costs. At the industry level, tire design improvements aim to improve safety for drivers and other motorists. And on a global level, sustainable tire technology seeks to lessen the impact on the environment.
Three tire manufacturers weigh in on how they are advancing tire design to meet these and other goals:
Advancement 1: Lowering Operational Costs
Reducing Rolling Resistance
Lowering rolling resistance is at the top of the list of design enhancements that can lower operational costs, which improves fuel efficiency and decreases fuel costs.
Various aspects of a tire’s design can influence the level of rolling resistance. These include the following:
1. Tire compounds, the blend of materials used to construct the tire, are key in fuel efficiency and long-lasting wear.
“The latest advancements in tire design for commercial trucks and vans focus on low rolling resistance performance and enhancements to ensure even wear and traction,” said Rob Williams, vice president of U.S. TBR sales for Hankook Tire America Corp. “For example, when a low rolling resistance compound is applied to the tires, it optimizes the tire profile structure through an even foot shape.”
When lowering rolling resistance, tire manufacturers strive to balance measures to save fuel with tire wear. Thomas Stacey, B2B product category manager -urban & regional, Michelin North America, Inc., said advanced compounding technology could maintain this balance.
“By adding a high percentage of silica to the tread blend, Michelin has managed to push the limits of rolling resistance so that you can save fuel without compromising tire longevity.”
Stacey said Michelin’s compounding technology could also improve wear, further reducing the operational costs associated with tire replacements.
“We use a unique material created by an innovative process in which some tread components are blended when in a liquid state,” he added. “The material this creates is more homogeneous, helping to get more miles out of the tire.”
Matt Schnedler, senior product manager for Truck and Bus Radial Tires at Bridgestone Americas, said combining high-quality materials and engineering to reduce rolling resistance could help achieve key fleet goals.
“Fleet managers typically seek out tires that promote uptime and maximize cost savings. Therefore, tires engineered for low rolling resistance and designed with high-quality materials that stand up to the rugged demands of fleet operations are critical to the overall fuel efficiency and performance of a vehicle,” he said. “Our number one goal is to maximize fleet performance while minimizing their overall operating costs. Some of our recent tire design advancements allow us to improve wear performance and rolling resistance simultaneously, leading to a more fuel-efficient tire that lasts longer.”
Bridgestone’s latest tire design improvements have simultaneously improved rolling resistance and tire life.
“Our new Bridgestone R213 long-haul steer tire features improved wear performance by 15% and improved rolling resistance by 6% over its predecessor, making it the most fuel-efficient steer tire Bridgestone has ever produced,” Schnedler said. “Improving performance in both areas simultaneously was unheard of previously.”
2. Casings, the body of the tire, can also influence rolling resistance.
“Technologies in our casing that contribute to lowering rolling resistance while also helping to improve the tire footprint for long, even wear are found in many of our tires such as our X One products,” said Stacey of Michelin. “Michelin’s PowerCoil technology is a new generation of lighter yet more robust steel cables used in the casing to deliver improved resistance to distortion and damage. PowerCoil technology, therefore, leads to better endurance and reduced rolling resistance and fuel consumption.”
Stacey said sidewalls, which are part of the casing, also play a role.
“Michelin has also incorporated fuel-efficient sidewalls to improve rolling resistance while not impacting the wear as seen in many of our tires like the MICHELIN X Line Energy Z,” he added.
3. Tread design also plays a critical factor in rolling resistance, along with traction and wear.
“To lower rolling resistance, tire manufacturers have been taking aerodynamic drag into consideration when designing a tire tread,” said Williams of Hankook Tire America Corp. “Appropriate tread depth and maximum stiffness ratio can increase resistance to wear. Hankook’s 3D Kerf Technology strengthens traction performance while enhancing block rigidity, minimizing energy loss, and contributing to rolling resistance performance.”
In 2018, two Michelin engineers won a European Inventor Award for their Regenion technology, extending tread life.
“Regenion technology uses tread designs that self-regenerate, mile after mile, thanks to 3D metal printing techniques, giving you the grip you need over the service life of your tires and in all conditions,” Michelin’s Stacey explained. “New sipes appear as your tires wear for improved mobility.”
“As sustainability and environmental impacts move to the forefront in the tire industry, tire designs will evolve to using more sustainable materials than they
do today.” — Thomas Stacey, B2B product category manager -urban & regional, Michelin North America, Inc.
Increased Range for EVs
Bridgestone’s Schnedler said advancements are being made to reduce rolling resistance for electric vehicles.
“The duty cycle for electric vehicles is limited due to range and charging cycles,” he said. “There is currently work underway to determine how to lower the overall rolling resistance of these tires to increase range while also meeting the other demands electric trucks need, such as increased load-carrying capacity and torque.”
Meeting Last-Mile Needs
COVID-19 propagated a surge in online ordering and at-home deliveries that significantly increased the demands on last-mile fleets. As a result, tire manufacturers are placing a focus on designing tires specific to their needs.
“The COVID-19 pandemic has accelerated the use of online shopping, which in turn has driven demand for last-mile delivery and the tires to support it. Last-mile delivery fleets need regional tires that are built for city driving conditions while offering enhanced durability and stability to meet the weight demands,” Hankook’s Williams explained.
“As durability in high-stress, high-scrub applications are required for tires, Hankook Tire has adopted decoupling grooves in our tire design, as well as reinforced sidewalls. to withstand curbing damage.”
In 2019, even before the pandemic, Michelin released its Agilis Cross Climate tire, designed for applications like local and parcel delivery fleets, food and beverage and temperature-controlled vehicles, telecom and utility fleets, and trades like landscaping, plumbing, electrical, HVAC, and pest control.
“The rise in at-home deliveries has led to a growth in cargo vans on smaller rim sizes (e.g., 16- and 17-inch). These vehicles need a robust commercial tire capable of delivering long mileages under heavy loads and withstanding harsh urban conditions such as stop and go tight cornering and curb scrubbing,” Michelin’s Stacey said. “The Michelin Agilis Cross Climate was designed specifically for this growing segment. Its MaxPressure Profile optimizes the tire footprint for better wear life under high pressure, heavy loads, high torque, and stop-and-go driving. The StabiliBlok design provides wider and longer tread blocks to resist extreme torque while providing cool operating temperatures under full load at high speed. Its CurbGard sidewall protectors resist curb scrubbing in urban environments.”
Advancement 2: Safety
Tires are a critical component to running a safe fleet, so it’s no surprise manufacturers continue to focus on ways to design safer tires by improving traction and helping them perform in adverse conditions.
Schnedler of Bridgestone said improved siping technology, the process of cutting thin slits across a rubber surface to improve traction, is one way that tires are getting safer.
“Advancements in siping technology have allowed for increased wear and traction at shallower depths, allowing for tires that provide similar wear as deeper tires while also meeting SmartWay requirements and giving the drivers confidence in the traction these tires provide,” he said.
Improved Performance in Adverse Conditions
Tires can be the difference between a safe trip and a dangerous one, especially in adverse conditions like snow, ice, and rain. Tire designs are addressing these needs, too.
On winter tires, kerf, a zigzag pattern on the tire, maximizes the friction between the tire and snow, which improves safety and handling. Traditionally, kerf for tires is two-dimensional, but Hankook Tire produced a three-dimensional groove pattern by adding another vertical shape.
“One of the most interesting advancements in tire design we’ve seen is 3D Kerf, which provides better traction to prevent tearing and irregular wear for long mileage,” Hankook’s Williams said.
Tire design is improving for vehicles that operate in wet conditions, too.
“The Michelin X Multi Energy Z 2 has a unique tread design that utilizes a regenerating tread sculpture, an alternating channel groove design that evolves as the tread wears, providing water evacuation throughout life,” Stacey said. “Raindrop grooves at the midpoint of the crown also provide additional water evacuation as the tread wears. This allows the tire to maintain its performance throughout the life of its tread, maximizing the fleet’s investment and the driver’s confidence in safely maneuvering through on-ramps and turns, especially in wet conditions.”
“One of the most exciting advancements for fleets, still currently in development, is our air-free tire.” — Matt Schnedler, senior product manager for Truck and Bus Radial Tires at Bridgestone Americas
Cooler Running Compounds
As demands on fleet vehicles grow, tire temperature becomes a greater factor in safety. Schnedler said Bridgestone has designed compounds to handle the heat.
“One vast improvement in tire safety in the past ten years has come through the advancements of cooler running compounds,” he said. “In today’s world, trucks are going faster with less downtime coupled with airflow restrictive aerodynamics intended for gains in fuel economy — all of which contribute to tire heat. With the advancement of cooler running compounds, fleet owners and operators can meet market demands efficiently and, more importantly, safely.”
Advancement 3: Lessening the Impact on the Environment
On a global level, the way tires are made can have a significant impact on the environment. Advances in tire design are helping to reduce emissions and waste.
Reducing rolling resistance helps fleets keep fuel costs in check, but it also helps cut emissions.
“Low rolling resistance technology can effectively decrease carbon emissions by improving fuel efficiency,” said Williams of Hankook.
Tire manufacturers are also working toward reducing the number of tires that wind up in landfills. Retreading is one way to cut that waste.
“The scrap tires that commercial trucks and vans produce also have a major environmental impact,” Stacey of Michelin said. “Tire design advancements can increase the retreadability of the tire so that fleets get more use out of the original casing and lower the number of scrap tires that end up in landfills.”
Schnedler said that by designing tires that are more fuel-efficient and have a longer lifespan, Bridgestone helps fleets reduce their environmental footprint by decreasing carbon emissions and tire waste.
Based on BASYS manufacturing data, “Bridgestone casings are the most retreadable casings in the industry, and state-of-the-art advancements in retread design are leading to the adoption of retreads in more and more commercial fleets — thus positively impacting the environment by delivering landfill avoidance, reducing oil use, and more,” he said.
Williams noted that retreading reduces the number of tires in landfills and saves valuable resources used to make new tires.
“When tires can be regrooved and are retreadable, resources can be conserved, and fewer tires are discarded,” he said. “For example, the Hankook SmartLife Premium casing, in combination with the Hankook Premium retreading, ensures an increase in tire life of up to 250%.”
Another opportunity to reduce the environmental impact of tires is through advanced casing technology.
“This can lead to a decrease in lost tires, meaning less trash and less pollution,” Williams said.
“In the future, Hankook Tire sees various design improvements to meet the demand for autonomous driving and sustainable tire development.” — Rob Williams, vice president of U.S. TBR sales for Hankook Tire America Corp.
Using Sustainable Materials
Tire designs have also been evolving to use more sustainable materials.
“The Michelin VISION concept is manufactured from bio-sourced and recycled materials, leveraging the high-tech materials expertise of Michelin and its partners to achieve the objective of 100% sustainable materials by 2050,” Stacey said. “This innovative approach minimizes the tire’s environmental footprint and integrates its lifecycle into a circular economy model aligned with Michelin’s corporate values.”