Opinion: A new "golden age" for passenger tire retreading

The tire retreading market is well established in its applications for truck and OTR and aircraft, especially in the latter two segments where the price factor of low-cost tires alone cannot compensate for yields and, as in the case of aviation, do not meet the required certifications and quality levels.

Looking at the chart alongside, which correlates the maximum load capacity with the speed in operation, we notice that retreading is currently concentrated almost exclusively in the upper part of the graph, where we find products more stressed both in load and speed.

The car tire, which would be more suitable for retreading, is almost excluded, apart from some niche markets such as the 4x4.

The retreading of passenger tires

Leading car tire retreaders have had to face the challenge of low-cost tires decisively, most of the time having to reduce their product portfolio or even divest their business. And those who remained active had to focus on niche markets that could still be profitable.

But things could change and within a short time.

The combination of several factors such as new product developments, legislative requirements for fuel economy reduction, the exponential growth of the electric-powered vehicle market, and greater environmental awareness and global sustainability could bring car tire retreading to the fore. 

The automotive industry’s search for a reduction in fuel consumption finds the tire a valid contributor through lower rolling resistance.

The improvement in rolling resistance is achieved both with the development of specific compounds but also with a tread pattern with low groove depth.

While this has a positive effect on the reduction of fuel consumption, it unfortunately leads to a shorter lifespan of the tire.

The lower rolling resistance does not have a significant impact on traditional vehicles but on electrically powered vehicles can make a substantial difference, significantly increasing their range.

In EVs, you have higher masses due to the weight of the batteries and a powerful torque that is instantly discharged at the start, the combination of these two factors is putting a strain on traditional tires.

The first interventions by tire manufacturers have led to a strengthening of the carcass structure to support the increased weight and of course the development of new materials for the tread compounds that have greater resistance to abrasion.

Unfortunately, the problem is not completely solved, especially if the end-user tends to favour a driving style that maximises the torque characteristics of EVs. 

These factors lead to having intact carcasses with prematurely worn treads and tires that have reached the end of their useful lives.

This represents a great opportunity to give a new boost to the retreading of car tires, thanks also to the greater public interest and a change of course by the legislator, especially in central European countries.

In Germany, it was enough to broadcast a prime-time reportage on the main German television channel in the evening to trigger a spasmodic search for retreaded car tires by the public.

There are many indications that key car manufacturers are interested in including retreaded tires in the homologation process for new cars to increase environmental sustainability indexes.

This additional factor would lead tire manufacturers to revise their design standards to have a tire structure that allows full retreading, whose current rate of retreading is less than 80%.

Airless "Tires" (NPT) 

Tire manufacturers are focusing their efforts on advanced designs and concepts to define the future of their products.

The activities are focusing on what now seems to be the evolution of the traditional tire, a tire without air with NPT (non-pneumatic tire) technology.

Here, the main advantages come from the absence of air that eliminates problems related to puncture and burst while avoiding the sophisticated pressure control systems.

The airless tire, currently available in only a few industrial applications, as in the case of Michelin's Tweel, has a brand new construction, a tread band anchored to a lamellar structure with sidewall and rim function, which is fixed directly on the vehicle.

The useful life of the structure could go beyond the two or three retreads normally achievable with premium truck tires, opening a retreading market that does not currently exist. 

In June 2019 at the Movin'On Summit in Montreal, two years after the presentation of the concept, Michelin revealed its vision for the future of car tires, UPTIS (Unique Puncture-Proof Tire System) with the primary aim of eliminating the puncture or burst problem, which will be launched on the market in 2024.

Michelin has declared a retreadability of up to six times and identifies in this product the rebirth of the retreading market for car tires, with “rechargeable” tread through 3D printing technology.

Alessandro Villa is a rubber industry consultant with over 30 years of experience, mostly in the tire sector