Kraiburg holds first summit meeting

At the end of June, Kraiburg Austria held its inaugural “Retreading summit” in the village of Leogang. Some 70 guests from eight European countries and from Russia participated in the event, which was devoted to the most pressing current subjects of interest within the retreading sector. These included the repercussions of advances related to truck tread design patents and what this means for Kraiburg’s own in-house tread development. A second emphasis was presented by Hans-Jürgen Drechsler from the German tyre trade association (BRV) and Christoph Priewasser, product manager at Kraiburg Austria, about the latest interim results from the BIPAVER “Re-Tyre” project and Kraiburg’s parallel undertaken “tyre labeling” project.

Following an official welcome from Kraiburg directors Thorsten Schmidt and Stefan Mayrhofer, European patent attorney Edith Vinazzer introduced the guests to the main points on registered design rights and patent law. Under current European law, the originator of a design is automatically protected against copying for a period of three years without needing to apply for industrial property rights. Further design protection can be applied for through the submission of a design patent. These are initially granted for five years in the first instance and can be renewed up to four times for five years at a time. In order to be eligible for this protection, a protected design must possess visually identifiable individual characteristics, or in other words it must be recognisably different from other existing designs. In relation to Kraiburg Austria’s tread development this means new retreading patterns must be designed in-house to a much greater extent than they previously were.

Dieter Hasenkopf from Kraiburg’s innovation team used the new K228 pattern as an example to illustrate how this process might work at Kraiburg. Like the already introduced K74, K224 and K225, this pattern is also an entirely in-house development that Kraiburg registered to obtain legal protection for the design. Delving into further detail, Hasenkopf described the mould construction and stressed the extra complexity and expense associated with meeting the required limits set out by the tyre label. A tread must first be optimised for noise emission and its performance on different casings simulated. At present, Kraiburg is extending its know-how in the field of simulation and has called in the skills of Professor Dr. Günther Willmerding from German firm Steinbeis GmbH & Co. KG for this purpose.

In order to enable Kraiburg’s designs to be used in mould cure retreading, the company has collaborated with Cima Impianti since 2012 on circular mould construction. In her presentation, Cima Impianti sales manager Daniela Fanti outlined the design adaptation process use to adapt Kraiburg treads for mould cure retreading. Mould designers are going about this task by taking the Kraiburg CAD data for the flat mould as a basis and transferring them to a circular mould.

Retreads and tyre labeling

The second pat of the Kraiburg Summit meeting focused on tyre labeling. The BRV’s Hans-Jürgen Drechsler spoke on the mandatory type approval test for commercial vehicles in force in Europe since November 2011. Although retreads are exempt from the labelling requirement until 2017, an interim policy is needed to ensure the retread business will still be viable beyond this deadline. Further criteria for inclusion in the type approval process, in addition to the requirements for retreaded tyres under the current legislation, ECE 108/109, are rolling resistance, noise emission and grip in wet conditions. At the same time, this lays the foundations for tyre labelling under 122/2009/EC and 1235/2011/EC. The worst case scenario is that retreads will be subjected to the same procedure as new tyres. As there is a far greater number of variants due to the combination of different makes of casing, and material plus dimensions and processes – BIPAVER estimates that around 8,000 different options exist for truck tyres – retreaders would be faced with testing costs high enough to put them out of business, as each option would costs around 5,000 euros. 

In setting up the “Re Tyre project”, which attracted EU funding to the tune of 2 million euros,  BIPAVER has created a platform that seeks to come up with a political solution for retreaded tyres which will accommodate the requirements for the type approval test and the tyre labelling legislation while remaining economically viable for the retread business. Kraiburg is the only retreading material manufacturer to join the various associations and retreaders in this project.

In the second part of his address, Drechsler disclosed the interim results of the tyre test that are currently being conducted. These suggest that the second aim of the project, the development of a simulation tool that will provide reliable and conclusive insights into a retreaded tyre’s properties and into whether it will meet the required criteria, is also attainable.

Retreaded with Kraiburg – second-class tyres?

Kraiburg is also engaged in its own internal “tyre labeling” project, concentrating on offering its retreading partners products (tread compounds and tread designs) and services (adaptations of the retreading process) for a labelling system that conforms with all applicable laws. The company’s aim is to make a substantial contribution to a secure future for the retreading industry. Christoph Priewasser, product manager at Kraiburg Austria, finished with the first set of results. These confirm that the quality of retreads is greatly influenced by the quality of the materials used to make them, in conjunction with modern manufacturing technologies. Successfully marketed patterns from the K_base, K_tech and K_plus product lines are already making it possible for retreaders to make tyres which are on a par in terms of rolling resistance with new tyres made by reputable manufacturers.