Article published in the March/April issue of ERJ
Editorial: Testing time for tire makers
A few years ago, I attended a data management conference for the oil & gas industry, where a market analyst astounded delegates by advising: “Never trust statistics unless you have actually fiddled the figures yourself.”
The apparent faux pas came to mind with the recent revelation by Nokian Tyres’ CEO Ari Lehtoranta that the company had in the past fixed the results of third-party tire tests.
The company, he admitted apologetically, had for a time supplied specially-made tires to independent test organisations in order to bump up the ratings for the company’s products.
Unsurprisingly, the revelation did not go down well with Nokian shareholders, other stakeholders and customers – with reports of possible legal action against the company.
Also upset were rival tire manufacturers, especially when Nokian officials subsequently suggested that fixing tire tests like this was common practice in the industry.
Of the tire makers contacted by ERJ, Bridgestone, Continental, Hankook and Michelin all issued strongly worded statements countering the suggestion of malpractic
Typical was the response from Michelin, which insisted that it had “never designed or manufactured tires specifically for tests conducted by the media, automobile associations or any other organisations.”
Without any further evidence, it can only be stated that Nokian’s transgression was a temporary, one-off misjudgement, and the claims of widespread malpractice in the tire industry an aberration on the part of its officials.
Even accepting that, though, there remains another question mark over the test houses involved and the rigour being applied to sourcing representative samples for testing – as well as the rigour of the tire makers in making sure this happens.
Clearly, foremost among those requiring reassurance about the integrity of test data from the tire industry are the automotive vehicle manufacturers.
These OE clients work closely with tire makers in developing tires to ensure optimum safety, comfort and performance for drivers of their new models. But there are concerns about the lack of openness and information-sharing by tire makers around these programmes.
These issues extend, it seems, to the high-tech world of virtual prototyping, with leading automotive OEs’ complaining that they are being hampered by a lack of standardisation in tire-manufacturing and testing processes.
Prototype simulation is an essential part of car development, as important as modelling hardware assembly, Guenter Leister, Dailmler head of tire and TPMS development, explained in a panel discussion at the recent TTE conference in Hanover.
“In vehicle protoyping, we need to have a complete simulation environment,” said Leister. And, for us, the weak point is the tire model. The risk is that we may make the wrong decision because the tire model is invalid.”
According to the Daimler expert, a major challenge faced by all vehicle manufacturers is that, with some limited exceptions, there are no tire models that are “parameterised in a cross-tire-manufacturer model”.
Leister went on to call for the development of handling, comfort, and durability tire models in a cross-vehicle and cross-tire manufacturing manner.
These views were echoed by Gregory Smith of Tyre CAE and Modelling engineer, who urged a move to standardisation of test procedures run on tracks around the world.
This, he suggested, would help avoid the current situation where a tire maker tests tires on a vehicle at great cost but then gives the tire to consultants and OEMs to run the same costly tests on the same tracks.
“So, the tire gets tested four or five times in order to establish the performance characteristics,” he remarked. “The only reason the tire is being tested so many times is that we cannot agree on a single standard way and then just share the data.”
Clearly pressure is growing on several fronts for tire manufacturers to get together to raise standards in the critical areas of testing and development.