South Africa’s heavy vehicle transportation sector is a highly competitive industry, and those involved in it are constantly looking for ways in which to save costs.
Most transport companies understand that investing in a top-quality heavy transportation truck and trailer will ultimately deliver the lowest cents-per-kilometre. However, once this vehicle is out of warranty – and the time comes to start replacing for example brake linings with aftermarket components – opting to purchase the most economical product may not be the most financially prudent decision.
“A highly critical part of any truck and trailer combination is the braking system. All too often, we read of truck and bus accidents, which are invariably very serious,” says Transportation Components’ Sales Manager Patrick Bruinette, who has over three decades’ extensive experience in the field of heavy transportation and vehicle braking.
Bruinette explains that the sheer weight of a truck tends to amplify the consequences of an accident – as does the number of passengers carried in a bus.
“For this reason, when it comes to heavy vehicle brakes, the quality of both the maintenance and the aftermarket parts that are fitted as replacements are of crucial concern,” he adds.
Truck and bus accidents are often blamed on faulty brakes. However this is not always the case Bruinette observes, as the way in which drivers operate their vehicles and use their brakes is also a significant cause of accidents.
“For example, in the case of a truck-and-trailer combination, we find that the drivers drive down hills using the trailer control valve only, which means that only 50% of the braking system is being applied,” he explains. The problem arises when an incorrectly-used braking system starts overheating and friction- and brake-fade diminish stopping efficiency.
Friction material has certain restrictions – the hotter the friction material gets, the less stopping power it has. This loss is called ‘friction fade’.
On the other hand, ‘brake fade’ happens when the brake drum starts heating up and expanding; and the brake chambers have to push out further to exert effective force on the drum. The longer the stroke the diaphragm-type brake chamber has to make, the less efficient braking becomes, and is consequently referred to as ‘brake fade’.
Apart from poor driving habits, maintenance – or its neglect – is another contributory factor in many truck and bus accidents today. For example, Bruinette has experience of supplying parts for a truck that had been driven from Harare to Johannesburg with the brakes on only two of its eight wheels actually in working order. “Unfortunately, incidents like this are all too common,” he continues.
Most mechanics who work on heavy vehicles understand the critical nature of the work they are doing. However, what they have little or no control over is the quality of the aftermarket components that they are fitting.
In the very competitive heavy transportation industry, those in procurement are frequently under pressure to keep costs to a minimum. In addition, fleet owners/operators often do not fully understand the very considerable differences in price-related quality which exist in components such as brake linings.
Transportation Components has taken samples of its brake lining friction material and tested them in a laboratory, which has given them a rule-of-thumb guideline as to the durability of various friction materials in service. “Compared to various lining materials from second-tier manufacturers, our friction material original equipment manufacturers (OEMs) Duroline’s brake liners and Eren’s disc pads – which are the ‘gold standard’ in the industry – proved to between 30% and 50% more durable,” asserts Bruinette.
“We put a lot of ongoing effort into educating fleet owners and others in the transportation industry about the varying quality of brake friction material,” he continues, adding that Transportation Components offers its customers parts that match OEM quality but at a considerably reduced price.
Bruinette however cautions that, for companies importing components, the South African Bureau of Standards (SABS) issues a ‘letter of authority’ (‘LOA’) which gives permission to import specific components provided these parts meet certain minimum standards. Fleet owners need to be aware of this, and when buying low-priced components need to ask to see the supplier’s LOA, in order to ascertain whether it is legally correct; and whether the components which are being procured meet the required standards.
Heavy vehicle owners/operators also need to be aware of potential issues in the relining of brake shoes. This is a very specialised operation, particularly when it comes to riveting linings to brake shoes. A special piece of equipment is required to make sure the rivets are both removed and fitted correctly.
“There have been instances where rivets have been simply drilled out, a procedure which tends to enlarge the hole in the shoe. Sometimes brake relining shops will use one size of rivet – irrespective of the size of the mating hole in the brake shoe. Substandard practices such as these can lead to problems when shoes that have been relined in this way are refitted to trucks,” Bruinette advises.
A further important aspect that those involved in the maintenance ‘chain’ – from the fleet or vehicle owner to the mechanic – need to be aware of, is the importance of adherence to the specifications on the data plate (which is usually attached on the side or at the back of the vehicle).
However, experience has shown that the specifications on the data plate are quite often ignored, explains Bruinette. Trailers, in particular, are often given only cursory maintenance, while the truck-tractor receives the very thorough levels of maintenance. “It is vital that trailer brakes are maintained according to the specifications on the data plate, as it is the trailer that has to actually carry the load, and the trailer brake system which comprises at least 50 percent of the complete vehicle combination braking system,” he continues.
“Ultimately, in highlighting these factors, Transportation Components is concerned to reduce the cost-per-kilometre for heavy-vehicle operators by supplying top quality aftermarket parts and, in so doing, assisting drivers, mechanics, fleet managers and owners.
Too often the focus is on the initial purchase price of the vehicle – with subsequent disregard of the quality of components required to keep the ‘rubber on the road’ and the vehicle operating at peak efficiency, reliability and safety. Transportation Components has been striving to change the prevailing mind set, and through this educational process, working to contribute to a safer, more profitable transportation industry in South Africa,” he concludes.