Flexion technology is something that we are beginning to hear a lot more about from tyre manufacturers as the new standard, now backed by the European Tyre and Rim Technical Organisation (ETRTO), gains recognition in the agricultural world.
Standardisation of terms
The benefits of constructing a tyre which can operate safely and effectively at different pressures have long been appreciated.Michelin was pioneering new methods of carcase construction back in 2004 with the introduction of its 'Ultraflex' technology.
Since then, the terms 'IF' for improved flexion and 'VF' for very high flexion have been adopted by the trade with a fixed standard for their application to tyres. Both are used in comparison to a 'standard' tyre i.e., the type of tyre normally fitted to an agricultural vehicle. A tyre with an IF rating is designed to carry a 20% heavier load at normal operating pressure, or carry a normal load at a 20% reduction in pressure. For a very high flexion tyre the figure is 40% for both parameters.The advantage of safely running at a lower pressure in the field is the increase in ground area contact for a given load. This will obviously reduce the ground pressure and allow the tyre cleats to interact with the soil across the entire width of the tyre.
High flexion tyres are often associated with the need for wider rims. The emphasis has also been on fitting them to tractors rather than implements or trailers.Improved flexion to Michelin row crop tyres
Michelin extended the range of machines to which this type of tyre could be fitted earlier this year by launching row crop tyres that met the IF standard. They have now added a further three sizes to the original two.The company claims that these new tyres are designed specifically for use on self-propelled and trailed sprayers, and on low to medium horsepower row crop tractors from 70-180hp.
They are now available in the following sizes - IF 380/90 R50 167A8/167B; IF 320/85 R38 151A8/151B; IF 380/90 R46 165A8/165B; IF 320/90 R54 159A8/159B; and IF 320/90 R50 158A8/158B.