Starco HT range re-certified for higher speeds
The speed rating of agricultural implement wheels and tyres has traditionally often been limited to 40 km/h, a limit reflecting the restrictions historically imposed on general agricultural tractors not equipped with suspension. This absence of a suspension system was a deliberate design feature that optimised field performance, and the known limitations – the affect upon stability, ride and road holding at increased speeds – were in past times not considered economically important.
In recent years, economic pressures have led to the advent of a new generation of tractors fitted with suspension, such as the JCB Fastrac range of tractors. Suspension systems allow for higher working speeds, improved ride and stability on the road – giving farmers the potential of increased productivity. This development has eliminated the need to transfer produce to a separate road vehicle for transport to the market; the same tractor can now comfortably tow the trailer with its payload to market along the highway.
Tractors with higher speed capability were often limited by the speed rating of the wheels and tyres on the implements and other ancillary equipment it tows. Today, however, many implements, such as hay tedders, now also utilise the field support wheels as road transport wheels – and thus require wheels and tyres to match the speed capability of the newer high speed tractors. Wheels and tyres for hay tedder applications require strong and durable wheel bearings, a tyre construction and rubber formulation that can withstand the usual loading, transient vibration and shocks encountered in variable field conditions. Steel wheels subjected to constant abrasion from earth and stubble, as well as the high acidity of straw and other organic materials, also require superior rust-prevention and paint coating.
In response to the trend towards higher speed operations, Starco has re-certified its Starco HT tyre range to a rating of 50 km/h. This re-certification included comprehensive proof testing of the wheels and tyres, and covers the following dimensions: 15×6.00-6 61B (4PR), 16×6.50-8 72B (6PR), 16×9.50-8 76B (6PR) and 18×8.50-8 81B (6PR).
Starco says this re-certification is another step in upgrading its agricultural wheel product range. The company’s engineers are now in the process of re-certifying numerous products for both higher speeds and increased load ratings, reflecting the general upward trends in implement design and technology throughout the agricultural sector. The Danish company adds that the re-certification of its wheels and tyres is being undertaken in close cooperation with the company’s main OEM and aftermarket customers.