Hankook launches dedicated tyre for electric buses e-Smart City AU56

Hankook has premiered the new e-Smart City AU56 tyre developed specifically for electric city buses at The Tire Cologne 2024 held in early June.

The new model is said to “meet the special requirements of electric buses through low rolling resistance, high load capacity and excellent grip. Thanks to cutting-edge technologies, it enables a higher range per battery charge while efficiently transferring the high torque to the road. In addition to this the new tyre is optimised to give it a higher weight rating”.

Electric bus tyre Hankook e-Smart City AU56 will initially be available in the commercial vehicle size 275/70 R 22.5 and is suitable for all axle positions. The tyre carries both the M+S label and the snowflake symbol (3PMSF), which confirms its suitability for use in winter. It also has a new pictogram in the form of an electric bus on the sidewall to explicitly identify it as an electric bus tyre.

Hankook electric bus tyres: focus on new technologes

Tyres for electric buses, to achieve the maximum range per battery charge, need to have low rolling resistance as well as the need to safely transfer the high torque of electric vehicles to the road without generating excessive abrasion. The tyres also have to handle the high weight rating of electric buses due to the heavy battery. In addition, low rolling noise is a particular requirement in city traffic, increasing passenger comfort.

Bus tyres are subject to high mechanical loads which is why the new e-Smart City AU56 has strategically reinforced tyre sidewalls to protect against curb and bus stop bay impacts and damage. The sidewall is designed so that the tyre is as robust as possible, while also meeting all the requirements of everyday use in a city setting, Hankook states. Additional security is offered by the new three-stage indicator, which shows the sidewall wear at a glance.

Increasing efficiency of public transport through tyres

For the development of the e-Smart City AU56, Hankook stresses it utilized state-of-the-art technologies including AI-assisted design, tests using digital twins and 3D-printed tread patterns.

The e-Smart City AU56 has S-shaped sipes between the lateral and tangential tread blocks to improve the interlocking between the blocks. “This extends the durability and increases the grip, which is needed in view of the high torque. Three-dimensional zig-zag lines within the tread blocks also help with this. As the tread depth decreases, concealed grooves and sipes are exposed, made possible by 3D-printing technology, ensuring the required safety, traction and adhesion on wet surfaces over the entire life cycle. Small, step-shaped blocks ensure even wearing and prevent stone trapping, further extending the tyre’s life”, in Hankook’s words.

The e-Smart City AU56 is designed for regrooving and retreading, which is made possible by additional tread rubber and a reinforced carcass.

Guy Heywood, Vice President Marketing Strategy Truck and Bus at Hankook Tire Europe explains: “We’re very proud to present our first product developed specifically for all-electric city buses with the e-Smart City AU56. This tyre increases the efficiency of public transport and advances the transition to electromobility. Its low wear rate enables long-term use, thus reducing costs. High-strength materials and innovative design ensure durability even under extreme load conditions. Its structure also makes it ideal for regrooving and retreading, which contributes to reducing resource consumption.”