The tyre market has faced a number of challenges over the years, with customers often not seeing beyond the black rubber circle itself and therefore choosing the cheapest option to keep operating costs down. Evidence has shown this approach to be a false economy, particularly with the availability of retreads, which offer a different option and have the added bonus of ticking the sustainability box.
In the works is a fresh look at how retreads are rated for rolling resistance, wet braking and noise, set to be announced by the end of the year.
“As far as we know from official documents, the EU regulator is expected to publish a proposal for TBR [truck, bus and radial] retread labelling by Q4 2023,” explains Krzysztof Michalik, head of retread, Bridgestone EMIA. “That means, at the moment, we don’t know how that proposal will impact our operations because we first need to get some more clarity around the test method and grading approach.”
“The reason the EU is introducing retread labelling is to create more transparency for the consumers of retread products,” adds Siljana Lietz, head of ContiLifeCycle, Continental’s product lifecycle approach to maximising tyre longevity. “Generally, retreading is considered a recycling solution, as around 70% of the materials of a new tyre can be reused.”
PERCEPTIONS
Continental believes in the sustainability of retread products, and has invested heavily to create retread solutions that are attractive to customers (see also box, pp11-12). But, as Lietz acknowledges, one of the key challenges that the company faces remains the perception of the tyres themselves. “Retreaded tyres from Continental fulfil the same quality and performance aspects as our new tyres,” she assures. “Moreover, our target [for the tyres] is ‘Looks like new, runs like new’.”
Another challenge, says Lietz, is the competition that retreads face from cheaper (new) Asian tyres. “We believe that the requests from fleets to provide lifecycle solutions that support a sustainable approach will grow.”
Michalik agrees that truck and bus fleets can derive a lot of benefits from running retreads. It’s an approach that led Bridgestone to buy retreading specialist Bandag in 2006, with full integration of the company into the Bridgestone fold by 2010. “Fleets can save money [with retreads] and contribute to a sustainable society,” he reasons. “For example, retreads from Bandag contain up to 75% recycled and reused material, contributing to sustainability and circular economy. Reusing the worn casing as the main retread component creates a saving of up to 70 litres of oil, up to 32kg of rubber and 14kg of steel.” In terms of overall running costs per kilometre, Bandag rubber can help achieve a reduction of up to 30%, compared with a new tyre. “Retreaded tyres generate up to 80% fewer CO2 and greenhouse gas emissions than new tyres in production,” explains Michalik.
Meanwhile, Azeem Khan, UK and ROI retread manager, Michelin Tyre, says the company looks at such savings on a case-by-case basis. “It very much depends on the size of the fleet and the company’s corporate social responsibility policy,” he reasons. “Major fleet operators want to demonstrate their sustainability credentials and tyres are often a fundamental part of that process. They will highlight in their tender documents that their fleet is operating on a multi-life tyre policy managed by the manufacturer, including the disposal of the end-of-life (EOL) tyres after the retreading process.
“The challenge for the tyre manufacturer is to provide security of product by ensuring a strong flow of worn casings into the retread factory, matched by consistent quality of production,” adds Khan. “A lot of the issues that can cause casings to be rejected can be easily overcome with customers once you explain the retread production process to them, which we do regularly with our Michelin Remix factory visits.”
There are varying levels of adoption of retreads throughout Europe, something that Khan believes is down to “shifting market dynamics”, rather than product acceptance. “Not all countries benefit from having a large tyre OEM retreading operation in-country, like the UK does with Michelin [see pp10-12] – and some countries have historically relied on smaller franchised retreading operations,” he says. “Following increased competition from Asian new tyre imports over the last six or seven years, priced to compete with retreads, some smaller retread operations closed or scaled back. Import tariffs then attempted to stem the flow of new products from Asia, but not sufficiently, contributing to the variations we now see across Europe.”
Khan adds that commercial vehicle fleet inactivity during Covid had an effect on the retreads world. “As new tyre sales fell across the sector in 2020/21, the knock-on effect has been fewer worn casings being available to retread in the following years,” he reasons. “The recovery of the market has been driven by new vehicles – and these will provide retreadable casings over the coming 12-18 months.”
“Historical and environmental reasons lead to variations in the use and perception of retreaded tyres,” adds Lietz. “For example, hot retreading solutions are more present in France and the UK, while the Nordic countries prefer cold retreading solutions. The perception overall, however, is similar,” she confirms.
“For the future, we believe that both hot and cold retreading solutions will become even more present in fleets because the sustainable aspect is supported by both solutions.”
WET GRIP
For one performance indicator – wet grip – there has been some debate about whether changes to the carcass or tyre pattern is the most import element when it comes to improvements of wet grip. Experts are able to settle the debate. “The carcass is key for tyre performance parameters such as handling, load carrying capacity, durability, comfort and rolling resistance,” says Michalik. “Regarding wet grip, we do not see a substantial impact of our carcasses to the grip itself, because it is taken for granted that the carcass will ensure the footprint contact shape. Therefore, pattern geometry, compound formulation, tread depth and tread void ratio are more relevant on the wet grip performance. This is proven by the fact that it is common to have the same wet grip label on same size tyres but with different carcasses.”
Khan agrees: “Generally, wet grip is a product of tread design and the materials used to produce that tread,” he explains. “Neither can work efficiently if the casing is not up to standard. We only use Michelin casings to produce our Remix products – and they undergo a complete forensic examination to establish their suitability for retreading before the retread tyre is manufactured. We also use exactly the same materials to manufacture the retread tyre as were used when the new tyre was originally manufactured.”
He adds that the casing is fundamental to the performance of the retread and explains that Michelin designs casings with the potential to be retreaded more than once. “The testing process prior to accepting the casing for retread is very important. Once accepted, we are effectively guaranteeing performance to be almost identical to that of a new product for the same conditions of use.”
The past five years have seen the commercial vehicle retread market grow by 4%, with more than 70% of fleets having used retreads at least once. With cost and sustainability benefits, the hope is for the new labelling to harness that growth and ensure that it is not only maintained but improved year-on-year for the foreseeable future.