Your tractor tyres are designed to bear heavy loads, the weight of your tractor of course, but also your tooling, they are solid and highly resistant tyres. However, you know very well that this doesn’t mean you can mount any size of tooling or add mass indefinitely, the limits in terms of load and ballast are entirely linked to your tyre model. These limits are essential and must be respected, for your safety to begin with, as well as to make your equipment last over time, to preserve your soil and make savings by having the best settings possible for your trailer.
Load and pressure are directly linked: the mass of the tractor, with its implements, crushes your tyres directly up to a certain limit, it’s the quantity of air contained in them (thus the pressure) which makes it possible to compensate for this crushing effect.
If you transport heavy loads, you must increase your tyre pressure to bear these loads. However, if there is not much air in the tyre due to its size, for example, it will not be able to bear a heavy weight. There is a direct relationship between the volume of air contained in a tyre and its pressure.
To define the right pressure, use weighing equipment for the front and rear axles. This will allow you to check the actual weight borne by your tyres and check that this effectively corresponds with the load index indicated on the tyres.
Never exceed this index if you wish to avoid damaging your tyres rapidly or risk bursting a tyre as a result of overheating when driving if you go well beyond the limits.
But bear in mind that there are some disadvantages to increasing tyre pressure. If you are working on loose ground with overinflated tyres, there may be very negative consequences:
Increasing the pressure in your agricultural tyres is the right solution when using heavy tooling but beyond a certain limit, this penalises the mechanical efficiency and in the long-term, slows down root development in your crops.
More than the pressure, it’s the volume of air in the tyres which matters if you wish to transport the heaviest loads, pull wider implements, or full trailers during harvesting, for example.
When changing your tyres, you can therefore take the opportunity to increase the rims and choose a wider set of tyres with a higher volume of air. By opting for bigger tyres, you will have more air to bear the mass without being obliged to increase the inflation pressure too much.
For example, for a speed of 30 km/h:
to pull bigger implements
With their bigger contact patch with the ground, large size tyres have many advantages:
An agricultural vehicle’s traction capacity is directly linked to its weight and to the balanced distribution of load transfer to both axles. For work requiring maximum traction, such as tilling, ballasting your tractor is strongly recommended, especially if it is light, in order to increase its traction capacity by rebalancing the load between the rear and front axles.
To optimise the driving capacity of your trailer, you can apply the following rule: the overall mass must not be lower than 50 kg per hp.
Example: if we take a 190 hp tractor, the mass necessary to ensure good traction will be a minimum of 9,500 kg minimum (190 x 50 = 9,500 kg).
Metal ballasting is relatively simple and quick to set in place if you have adequate lifting equipment. Like with all the other ballasting systems, there are numerous benefits:
To adapt the load distribution between the tractor’s front and rear axles, the best technique is to use metal weights.
You can increase or reduce the number of weights depending on the weight of your implements to optimise adherence to the ground.
In detail, metal ballasting consists in installing metal weights (often made of cast iron) on the tractor or its wheels (hubs or axles). Due to the heavy weights involved, you will require lifting tools to carry out the operation successfully.
For optimal ballasting, a few essential basic rules must be followed:
In any case, we strongly recommend that you do not use too much ballast on your tractor to avoid unpleasant surprises. Excessive ballasting effectively has a direct impact on your fuel consumption because your combination vehicle is heavier overall and therefore requires more power to work.
Unlike using metal weights, water ballasting is the most economical way to increase your tractor mass. As its name suggests, it involves filling a large part of the tyres with water, up to 75% of the tyre’s volume.
If your tractor is not heavy enough for the implements you use regularly, water ballasting is the right solution because it is used essentially on a permanent basis, due to the time it takes to prepare.
Before any action, you must check that your tyres are compatible by referring to the manufacturer’s user manual and ensure that your tyres have an air/water valve.
As with using metal weights, there are benefits to water ballasting that are related to ballasting in general.
To summarise, water ballasting is a solution that is:
Despite various advantages, there are some limits to this technique:
An alternative to increase your tractor’s load without increasing the inflation pressure or ballasting your tyres is to opt for low-pressure IF (Improved Flexion) tyres.
Made using more elaborate materials stemming from in-depth research and development work, these new generation tyres have a reinforced casing structure which means that they can bear up to 20% more load compared to a standard tyre.
With their innovative design, IF tyres have a huge internal flexion capacity thanks to their supple, resistant sidewalls.
By moving up-range, you will obtain all the benefits of a quality tyre with a more elaborate tread. The original design of the lugs which constitute the tread of IF tyres enable excellent self-cleaning and an increased traction capacity.
The heavy loads that you transport end up by compacting your soils and damaging the root systems of your crops. IF tyres are designed to work at very low pressure, as low as 0.8 bar, allowing you to considerably reduce the pressure exerted on the ground with a larger contact patch and a better load distribution.
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