Treading in your tyres tracks
With the plethora of tyres available on the market and the multitude of potential applications they can be used for, keeping one’s fleet rolling can leave you a bit flat. FOCUS explores why this is literally often the case, and what options exist to keep operators pumped-up.
When owners kit out their vehicle(s) with a new set of tekkies, how much thought goes into what it takes for the chosen tyres to be acceptable for use?
The up-front cost on a 26-wheel rig would be a big factor, as would – to any serious, professional operator – the overall lifecycle and maintenance costs. Retreadability on a commercial vehicle tyre is another important consideration (a practice, incidentally, highly discouraged when it comes to passenger vehicles). Naturally, one would assume that the correct tyre for the application is also chosen, though that’s not always the case …
Design and manufacture
So, how do you know that the tyres you’re putting on your vehicle have been properly developed to be reliable and give a long service life? Any reputable tyre brand will have subjected its designs to numerous tests, thereby ensuring that they comply with a range of safety, performance and environmental parameters. Goodyear, for example, considers more than 50 criteria during the development and test phase of a new tyre.
“For example,” says Wayne Nicholson, Goodyear Commercial PBU director, “Mileage, retreadability, endurance, dry and wet handling and traction are taken into account – to name just a few. Before tyres are released to the market, they have to pass an extensive testing process to make sure they fulfil our high quality standards and deliver value for our customers.”
Another well-known tyre manufacturer, Michelin, says that the region in which a tyre is to be used is also a major consideration. Luke Walsh, customer engineering support (CES) at Michelin South Africa, explains that Michelin has CES staff in four African countries, and a team in Dubai, covering all the major countries in Africa, to fully understand the conditions of use and customers’ needs in this geographical zone.
“This information is then analysed by the Michelin design team to ensure that the next generation of truck tyres incorporates the appropriate technology to meet customers’ needs. Prototype tyres are then produced and evaluated at our global research and development centres,” he explains.
Hitting the road …
“There are two distinct groups of vehicle operators,” notes Walsh, “Those that see tyres purely as an expense, and then the operators that see the purchase of tyres as an investment in their business.”
Choosing the incorrect tyres for the usage conditions is among the top mistakes operators make, according to Michelin. Bridgestone/MaxT Solutions reminds us that all tyres are manufactured with specific speed and load index markings – showing the maximum speed at which a tyre can support the load weight, indicated by its load index. It’s important to remember that commercial tyres denote two load index figures, for single and dual fitment.
All major tyre companies provide a full range of tyres to meet every individual application and have the facilities to help operators make the right choice.
… and staying there
The average lifecycle of a truck tyre is around six years. The correct level of maintenance should, therefore, be carefully planned. Michelin notes that there is a move towards outsourcing the management of tyres to dedicated tyre professionals. This is probably due to an increase in awareness of the role that tyres play in fuel consumption. “Up to 30 percent of a vehicle’s fuel consumption can be attributed to the tyres,” explains Walsh.
Clearly then, tyres are worth more than many realise, so keeping them well maintained is of utmost importance. Nicholson says that there are, however, a large number of local fleets that do not follow a strict tyre management policy; which is exacerbated during tough economic times when many fleet owners opt for cheaper alternatives.
The following back-to-basics tips should always be adhered to:
• Maintain the correct loads and inflation pressures;
• Rims must be correct and in a good condition;
• Check and adjust wheel alignment settings regularly;
• Match and rotate tyres where applicable;
• Correct and repair mechanical problems immediately;
• Ensure valve extensions for inner duals are fitted, as well as valve caps.
Tyres also need to be retreaded timeously. Walsh suggests that, in a good highway operation, the drive axle tyres are kept on the vehicle until they have reached three millimetre remaining tread depth.
Bridgestone/MaxT Solutions notes that retreading not only helps operators manage costs, but is better for the environment; reducing waste and consuming 26 litres of oil to produce compared to the 83 litres for a new tyre. Further, most tyre manufacturers will back their retreads with a warranty.
Exploring the future
“Tyres have experienced significant performance improvements over the years. The tyre industry is, however, evolutionary and not revolutionary,” says Nicholson, adding that the industry is unlikely to experience significant game-changing technologies and products – pneumatic radial tyres meet all application, performance and vehicle requirements.
That’s not to say, however, that modern tyre companies are resting on their laurels and not driving technology to boost the status quo.
By eliminating the need for external inflation pressure intervention, Goodyear’s Air Maintenance Technology (AMT), for example, can aid fuel saving and CO2 reduction while potentially improving tyre performance and tread life. The AMT mechanism allows tyres to maintain constant, optimum pressure without the use of external pumps, electronics and driver intervention – thereby maintaining proper tyre inflation.
Michelin, too, focuses a lot of its development on fuel saving and safety measures. Its Energy Flex Casing low rolling-resistance tyres aid fuel saving, while its Infinicoil technology – a continuous cable wrapped around the full circumference and width of the tyre – provides greater safety and increased mileage.
It’s clear then that, while some might view the not-so-humble tyre as just another expense, the correct tyres for the application – having been correctly maintained – are in fact an investment.