Retreading’s “new beginning” hinges on EC decision – Bipaver

Until 2015, retread tyres are outside the remit of labelling Regulations 1222/2009 and 1235/2011, but at the recent Tire Technology Expo in Cologne, Germany, Bipaver secretary, Ruud Spuijbroek presented the progress the organisation has made – and hopes to continue to make, if adequate funds are available – in what it believes could be “a new beginning” for small and medium enterprise (SME) truck tyre retreading, with labelling its catalyst. Bipaver used the event to explain in full the current details of its “Re Tyre” project, with the latest decision from Brussels on the future of the scheme to follow in the next month or two.

The potential economical and logistical threat of the European Union’s tyre labelling legislation to medium-sized retreaders, and the subsequent “Re Tyre” project – organised by European retreader association Bipaver – has been discussed at length in the September 2011 issue of the Retreading Special (also available to subscribers online at tyrepress.com). To summarise in the simplest possible terms, Re Tyre aims to research the effect of variations in the casings used on the potential rolling resistance and wet braking ratings of a retread, providing retreaders with a cost-efficient database from which to generate tyre labels for their products.

The political eco-consciousness prevalent in the Union, alongside its tendency to seek to aid SMEs is at the heart of Bipaver’s continued progress with Re Tyre. Helping a less raw material intensive and recycling-friendly group of SMEs to perform the necessary research to make retreaders take part in labelling could be a good opportunity for the EU to make good on its emission and waste reduction goals.

Starting from first principles Spuijbroek reiterated the demands improvements in weight capacity, horsepower, constant speeds and braking efficiency of the modern truck have placed on replacement components, such as tyres. He explained the deterioration of a new tyre as soon as it rolls off the production line means its viability as a casing for a retread is determined by it being “processed within a ‘Life Safety Zone’.” Currently, of course, “this ‘Life Safety Zone’ is determined by experience and the development of more sophisticated inspection machinery to ensure that truck retreads stay a safe and reliable option to new tyres.” The necessity of standardised testing processes, enabling a retread tyre model to be labelled, clearly makes the sophistication of the latter method a key factor in Bipaver’s project.

Looking at the casing suitability in relation to the quality of the final product, Spuijbroek explained that “the human eye is still our first piece of technology in the retreading of tyres. Using the eye, a trained tyre technician can quickly gain an overall impression of the general condition of a casing.  His ability to do this is based upon training and experience.

“The visual inspection determines, load index and speed symbol, age, signs of under-inflation, physical damage, contamination, casing break up and distortion. It is clear that the human eye however cannot detect the following in a casing: concealed rubber lamination, belt separation, stressed or concealed broken cords and porosity.” Technology’s gifts to retreading therefore include pressure testing for distortion; shearography to show rubber delamination and steel belt and rubber separation; ultrasound detects separations and porosity of cords, X-Ray any broken, stressed and spaced cords; and high voltage to find tyre penetrations in tread and sidewall, Spuijbroek listed. Ultimately, it is technology that has “given the retreader the ability to manufacture retreads equivalent to new tyres”.

Building on acceptance of retreads’ quality

So where does Bipaver see the “new beginning” for retreads? The commercial and legislative climate calls for purchasers to be given more detail about a product prior to purchase Spuijbroek argues. Commercial vehicle retreads, governed by Regulation ECE109 for the best part of a decade, must currently pass type approval tests and “with the continuous improvement of ECE 109 the quality of the retreaded tyre improves accordingly,” continues Spuijbroek – a situation that helped make them “widely accepted as a quality product”, and 40 per cent of replacement truck tyres in Europe. The EU’s strong trend towards finding sustainable solutions has of course increased the importance of retreads, while Brussels’ increased acknowledgement of tyres’ influence on road safety and the environment is evidenced by such legislation as labelling.

Bipaver’s proactivity as the representative of the European independent SME retreading industry – represented by the Re Tyre project discussed in September – can be seen as a way to help the EU implement retread labelling on schedule, without penalising SME retreaders, as Spuijbroek explained: “the matrix of casings and treads today could lead up to 8,000 varieties at an average €5,000 cost per label. Therefore the sudden imposition of a testing system in line with new tyres could spell the death knell for many European SME retreaders. Since the economic position of the retread industry and the absolute need for a level playing field it became clear that we were not able to finance the project with membership fees. Just to give you an impression. The total cost of the project is about 2.5 million euros.”

The Re Tyre project’s goal is to secure the future of SME retreaders through European Commission funded financial support in the development of a test procedure that avoids each retreader having to conduct individual tests – a proposal that drew favourable responses from pro-SME Brussels, according to Spuijbroek. From that testing, on a range of retread sizes and patterns conducted under the conditions specified for new tyres, Spuijbroek explains, “We develop an algorithm.” This finite list of well-defined instructions should avoid the necessity – and overwhelming financial strain – of individual testing.

“This is fine for wet grip and noise,” continued Spuijbroek, “but doesn’t the casing have an effect on the rolling resistance? The first milestone test will be to test some parameters, the rolling resistance in particular, of groups of casings of different ages (0, 2, 4 and 6 years) buffed to 2mm above the steel. If the measurements show minimal deviation in rolling resistance and once ‘scientific noise’ is eliminated, the project continues. But if there are significant differences, which will make the database unreliable, the project is abandoned. If the programme passes this first milestone a test programme of approximately 500 tyres will take place, to build the database and form an algorithm.”

Running the testing will first be BAST (the German Federal Highway Research Institute), then IDIADA (the Spanish Proven Ground in Tarragona, Cataluña). Then, Spuijbroek explained, “the algorithm will be developed by Vortech, specialists in the scientific field of applied mathematics.” The final programme will allow the retreader to generate labels for its retread products, by combining data derived from combining the algorithm with an existing and updated new truck tyre database of wet grip, tyre noise and rolling resistance data. The system “will become part of [the retreader’s] 109 specifications,” says Spuijbroek. 

The project’s total €2.5 million cost is met through EC funding of “over €1.8 million, or 75 per cent, less a contingency of circa 5 per cent to allow for partners going into administration during the project,” said Spuijbroek. The proposed deal will mean the investment requires retreaders to provide three reports: one on the relationship between casing and the tyre performance; one on the relationship between retreading process and tyre performance; and one on the relationship between treads and tyre performance – the performance in each case will be measured by the tyre label’s three performance indicators, wet grip, rolling resistance and tyre noise. Summarily the retreader will need to provide a model for predicting retreaded tyre performance.

Of course, Bipaver explains, the current plan for Re Tyre remains contingent on Brussels’ final approval; the organisation, and the national associations it represents must wait for this decision if there is to be “a new beginning” for reatreads

Related news:

• Bipaver “very uncomfortable” about truck racing retread ban
• “Re Tyre” aimed at securing the future of medium-sized retreaders
• Kraiburg playing an active role in Re-Tyre