Buyrite also supplies tyres for Agriculture
There are significant differences in tractor tyres despite the commonly held view that they are all very similar. It is important to use the correct tyre for the correct job as fitting the wrong tyres will result in poor performance. Slippage will slow down the work rate and cause higher fuel consumption.
In today's ever-changing times, machinery becomes increasingly sophisticated and powerful. In order to reap the benefits in these improvements, the operator needs to utilise the advances in modern tyre technology.
The modern tyre, be-it crossply or radial, is constructed with the following components:
Tread
This part of the tyre comes into contact with the ground and is made from a rubber strip that binds the casing and belt. The majority of the tread thickness is taken up by the tread pattern whose features depend on the use for which the tyre has been designed.
The tread must provide:
- Traction
- Self Cleaning
- Even Wear
- Directional Stability
- Fatigue & Shock Resistant
- Running Comfort
Casing
Consisting of rubberised plies, the casing's main function is to withstand internal/external stresses. However, above all it must adapt to the varying ground conditions to give maximum grip in the tread area. In crossply tyres, the plies run in an overlapping criss-cross pattern; on radial tyres they run radially.
Sidewall
Made entirely from rubber, this area between shoulder and bead, is designed to protect the casing from impact and resulting damage to the textile plies.
Bead
The bead consists of a metallic ring where the casing plies turn up. This is the critical point of contact with the wheel rim and must provide a positive anchorage between tyre and rim.
Belt
Located between tread and casing, the belt consists of a multiple layered supple fabric. Its function is to create a solid, stable support for the tread thus producing maximum traction, wear resistance and improved efficiency.
Inflation and Pressures
Correct inflation is of paramount importance for maximum safety and performance and need checking, when tyres are cold, at least once a fortnight and before any prolonged operation. This is particularly important if water ballast is used.
- Under-inflation will cause higher fuel consumption, irregular wear, overheating of the tyre, internal damage and ultimately tyre failure.
- Over-inflation will cause the tyre to be more susceptible to impact damage, lack of traction, reduced driving comfort and ultimately tyre failure.
Tyres fitted to 4 wheel drive tractors should be inflated so that the front wheel lead, usually between 1% and 5%, is not affected. Check with the machine manufacturer for exact limitations Excessive "Toe-out" will have the opposite effect i.e. more rapid wear on the inside tread shoulder and in Britain the off-side tyre will be most affected.
Field Work/Low Powered Drive
Surface cultivation generally involves lighter loads for which proportionally lower pressures can be used. Inflation pressure directly determines the pressure exerted by the tyre on the ground and the resulting soil compaction.
Use and Maintainance
Tyres should be regularly examined paying particular attention to the tread for signs of abnormal damage. Bead/rim area should be checked for chafing, rim damage, cracking and misfitting or movement. As tyres age when not in use, specialist tyres occasionally used should be checked for signs of deterioration before fitting. Tyres fitted to machines parked for long periods should be jacked up on their axles to remove the weight from the tyres and the tyres should be protected from direct sunlight.
Determining the Load on the Tyres
- On the rear wheels it may be taken that, when ploughing in damp conditions, the dynamic load is about 85% of that with the tool carried and raised. For heavy cultivation and ploughing, the tyres are usually at their maximum load capacity.
- On the front wheels the weight used is that obtained on a weighbridge with the rear tool lowered.
Advantages of Low Pofile Tractor Tyres
The development of low profile tyres together with new construction techniques and tread bar designs has resulted in major improvements in tyre performance. This has allowed increases in load capacity, while reducing seedbed compaction during cultivation, critical requirements for good crop establishments.
Tubeless Tyres
The cost saving benefits of tubeless tyres are: fewer breakdowns, faster fitting, easier repairs and no tubes to buy. Tubes may be fitted in any tubeless tyre if the rim is not suitable for tubeless fitment.
Water Ballasting
Some tractors need to be ballasted, particularly for traction when ploughing. In this case the weight per horsepower needs to be increased to about 60/65 kg. In addition to ballasting using iron weights on the wheels or the chassis, the tyres can be water-filled up to 50-75% as required. This partial filling leaves an air cushion within the tyre and thus the tyre losing none of its flexibility and retains its ability to react to load variations. The faster the tractor moves, the more the air is emulsified. A ballasted tyre needs its pressure checked and corrected more frequently. In cold conditions a nitrite-free ethylene glycol-based antifreeze should be added to the water used for ballasting tyres with or without an inner tube.
Repairs to Wheels
Repairs to wheels involving heat, braze or weld should never be attempted without removing the tyre.
Fitting and Inflation
Fitting and inflating tyres are specialist operations that require training. For reasons of quality and safety, these operations should only be carried out by tyre specialists who:
- check the condition (absence of distortion, cleanliness and fettling of the areas in contact with the tyre) and compatibility of the rims.
- use approved lubricants and specialised tools.
- have the expertise to carry out the work in accordance with manufactures specifications.
Unqualified tyre fitting may result in fitting difficulties and damage to the tyre beads. Buyrite Tyres has the expertise and the equipment to provide a full agricultural tyre service, both within the depot and on the farm.
