Tyres: keeping on the straight and narrow
Prime Mover's search for the low carbon truck continues with a look at one of the most neglected areas in the trucking industry, the piece of the truck which actually meets the road, tyres and the wheel alignment.
Looking for ways to save fuel, and as a result, reduce carbon tax exposure, often sees operators looking at the big ticket items, like aerodynamics or alternative fuels. There is one area of truck maintenance that is regularly neglected throughout the industry. It is also an area where there are genuine fuel savings to be had by any operator if they do the right thing. Correct tyre choice, carefully maintained tyre pressures and regular wheel alignment have all been shown, over the years, to be proven fuel savers.
However, the area of wheels and tyres is also one commonly neglected by many in the industry. It is an unglamorous part of the job and one that needs rigorous regular checking to be effective. It is also reliant on a consistent attitude throughout a trucking fleet to work properly – if one part of the chain doesn’t do its job then the work done by other people within the same organisation is wasted.
The subject of tyres and tyre maintenance is the cause of a lot of concern and consternation for transport company service managers across Australia. The many variables involved in tyre usage mean a proactive management regime is needed to ensure tyre use is optimized, and as a result, fuel use is optimised. There is a lot of work involved in simply keeping the correct tyre on the correct wheel, at the correct pressure and correctly aligned. All of this for just a 5% saving in fuel, and consequently a 5% reduction in carbon footprint.
However, there is an added bonus. Operators who run an efficient and well-managed tyre management system can also expect a substantial reduction in tyre wear, getting many more kilometres out of each individual tyre casing. Good management can bring an operator a substantial reduction in costs alongside the reduction in fuel costs and carbon tax.
The tyre manufacturers offer and publicise specific tyres designed to save fuel.
Under inflation causes the tyre to deflect beyond its design capabilities therefore affecting performance; and eliminating any rolling resistance benefits and potential savings in fuel costs.
“We are spending enormous amounts of money on research and development to produce the perfect tyre, but all of those benefits can be thrown out the window if all of these other factors aren’t brought into the picture,” says Continental Tyres National Sales Manager Commercial, Roy Norris. “You are going to destroy all of the good coming from a tyre if you are not going to maintain the vehicle correctly and have the right tyre maintenance. The most important factor of all is inflation pressure.
“There’s very little tyre awareness, tyre knowledge and tyre maintenance applied to driver training. Drivers are trained to drive the truck to maximise the efficiency of the vehicle but it is amazing how little drivers know about tyres. They should be taught to maintain the pressures properly and to look for any signs of wheel alignment wear.”
Irregular wear appearing on tyres is a clear indicator there is something wrong. Whether it be poorly maintained pressures or incorrect wheel alignment, they are both clear indicators of increased fuel use whenever they appear.
Technologies are available, and more sophisticated designs are in the pipeline, mounted in the tyre or on the tyre valve to measure the tyre pressure and temperature. These will monitor the pressure ensuring it remains within certain parameters. When the pressure in the tyre drops below a certain point the monitor sends a signal to a control box, normally mounted inside the cab, which will warn the driver about an under-inflated tyre. However, it is still up to the driver to stop and rectify the situation, but at least they are aware of the problem.
As well as having all tyres on a combination at the correct inflation pressure all of the time, it is also vital to ensure all of the wheels on a combination are correctly aligned all of the time to get the best fuel use results.
“We reckon that with all the wheels aligned properly you can expect at least a 4% reduction in fuel consumption,” says Mike Dobson, Managing Director of wheel alignment specialists Big Wheels. “Now trucks coming to us may not get that kind of saving if they are already doing quite well, but I would say about 80% of the trucks whose wheels we align can expect at least a 4% reduction in fuel consumption.”
It is recommended operators get the wheels aligned on all of their vehicles every 100,000km. Once the wheels have been aligned the first time, the subsequent alignment is simply maintaining the original fuel savings achieved after the truck was first aligned. Failure to keep up the wheel alignment maintenance will see fuel use rise back to the original level.
The Big Wheels website (at http://bit.ly/bigwheelscarbon) includes a carbon calculator to help operators calculate the kind of savings in fuel consumption and consequently, carbon footprint which are possible with the correct time management and wheel alignment. Simply enter the detail of the truck or fleet of trucks, the annual mileage and the amount of fuel used, the calculator will then come up with a tonnage of carbon dioxide emissions saved.
An important factor to consider within a fleet where there is a lot of interchanging of trailers and prime movers within combinations is to ensure all of the possible vehicles have their wheels aligned. In any combination, if one of the components has wheels which are incorrectly aligned then the wheel alignment for the entire combination is thrown out and consequently angles are changed, tyres fight against each other and fuel consumption rises.
“We get a lot of people coming in who just want the front aligned, but we try to talk them out of it,” says Mike. “You have to look at the whole vehicle, if the back is pointing the wrong way than the whole front is pointing the wrong way as well. Unless you do a total vehicle alignment you cannot guarantee that you are going to get the full benefit of the alignment.
“The better operators, those with a more professional attitude, are now doing wheel alignment as part of their normal maintenance. They have realised there is a huge saving to be made if they have regular maintenance done, whereas others will often realise they are wearing tyres out and take a truck in for wheel alignment, which is generally too late. They will have been using too much fuel for a long time by that stage.”
Depending upon the amount of work involved in aligning the wheels, a simple rule of thumb is the cost will be around $300 per trailer. Initial alignment may be a little bit more expensive but subsequent maintenance should be consistent and relatively trouble free.
It doesn’t matter what developments come along in tyres, in suspensions or vehicle combinations, the basic principles of truck alignment will always apply, as they always have done. If all of the wheels are pointing in the same direction as the truck travels down the road pulling trailers, similarly aligned, then fuel use will be minimised.
“When I talk to people, they don’t want to know anything about any carbon tax which may be introduced,” says Mike. “It’s one of those things which they are not prepared to worry about until it becomes law. It’s going to come, there are no ifs or maybe, it’s going to happen. They will suddenly realise that there is money they need to save there and then.”
It has always been the case, there are genuine fuel savings to be made, and therefore carbon tax savings as well, from choosing the right tyres, keeping those tyres well maintained and at the correct pressures. The problem for each fleet is to make that commitment and follow it through. All of the good work in one part of the maintenance program can be thrown away if tyre inflation pressure or wheel alignment is allowed to deteriorate.
This area has traditionally been a difficult one for operators to prioritise, tyres and a wheel alignment have never been big ticket items. Overwhelming evidence tells us a genuine commitment, by everyone involved in the truck, to getting tyre and wheel management just right can pay dividends and will reduce an operator’s carbon footprint. The question is whether the commitment can be carried through consistently because it is in the nature of the problem that being inconsistent in this area causes increased fuel use and increased carbon emissions.