Agricultural tyres are designed to work with heavy equipment, on a wide variety of terrain and under heavy loads. Tyres of machines used in modern farms must be prepared for difficult operating conditions. Special reinforcements and tread are elements that allow you to save fuel and extend tyre’s life.
There are two basic types of agricultural tyres available on the market: radial-ply and diagonal-ply tyres. How do they differ? The main difference is their internal structure. Diagonal-ply tyres have a multi-layered structure of the carcass with cord placed at an acute angle in relation to the direction of rotation. In contrast, radial-ply tyre’s carcass’ cord is perpendicular to the direction of rotation of the tyre. The advantage of diagonal tyres is their slightly greater resistance to mechanical damage. Radial tyres have a better grip on the ground and wear more slowly, they also provide better driving performance and less rolling resistance, thanks to which the vehicle uses less fuel.
How to extend the service life of agricultural tyres?
First of all – regular checking of tyre pressure. This parameter has a significant effect on fuel burning when driving on unpaved terrain. The pressure should be monitored with a pressure gauge at least once a month. It is crucial to keep it on the correct level – the basic mistake made by the operators is making the high pressure in the wheel too high. In most cases, 1 to 1,6 bar is a sufficient value. It should be remembered that in the case of agricultural tyres lower pressure translates into increased adhesion and also helps to reduce the risk of skid. However, only modern tyres adapted for driving with reduced pressure are able to ensure work safety.
– A change to radial tyres reduces fuel consumption by 3-12%, which reduces the operating costs of the vehicle. In contrast to the diagonal type, the deformation of the radial tyres proceeds in a suitable and controlled manner, which results in an increase in ground pressure area. This contributes to a lower degree of soil consolidation, on which the machine moves – which is especially important for operators of heavy agricultural equipment – says Piotr Sarnecki, Director General of Polish Tyre Industry Association (PTIA).
The tyres can also be protected by monitoring the looseness of linkages and worn steering knuckle bearing. Their occurrence may be manifested by the incorrect inclination of the wheels relative to the ground, and, as a consequence, faster wear of the tyres, especially the front ones. Steering knuckle is responsible for keeping the vehicle’s wheel in the position suitable for by the suspension and steering system. Contrary to what one might expect, we have an impact on the durability of switch bearings – they wear out much faster when the suspension geometry is incorrectly set. Correctly set suspension geometry has a significant impact on the tyre's running rate, and its regular inspection promotes longer tyre life.
Studies have shown that after exceeding 50% of the wear of the pad assemblies greatest decreases in traction forces appear1, and the further exploitation of the tyre is associated with lowering the driving economy – both on the soft ground and on the paved surface. Consequently, skid increases as well as the fuel consumption itself – which makes it impossible to continue working efficiently in the field. The same applies to the asphalt road – the level of fuel burning increases due to the increase of friction on the surface. Before buying tyres, it is crucial to carefully check the properties of the selected tyre model.
– Manufacturers of tyres accurately describe the parameters of the product’s use in its specification, which take into account many factors – such as the type of work, tractor weight and speed. Therefore, it is in the interest of users to read carefully the indications of their use – adds Piotr Sarnecki.
Over the past few years, leading agricultural tyre manufacturers have successfully launched two new categories of radial tyres, namely IF and VF tyres. They allow the use of a lower operating pressure, by 20% and 40% respectively, compared to classic radial tyres. The correct level of pressure for these tyres is based on the current wheel load. That makes it a lot easier for the user to avoid troublesome need to change the pressure after working in the field and before going on a paved road, after which the tractor moves at a much higher speed.
In addition to the careful selection of tyres and their rational use, one cannot forget about proper storage. Although the use contributes the most to tyre wear, storage conditions are very important. The tyre should not be directly exposed to weather conditions, high temperatures and their rapid changes, UV radiation in high intensity, and contact with chemicals or electrical discharges.
Find out more on ptia.org.pl/en
1 “Assessment of tyre tread protrusion wear in the aspect of farm tractors traction capacity”, Institute of Agricultural Engineering, Wroclaw University of Environmental and Life Sciences