Factors influencing performance, life span of a tyre
The worst and biggest enemy for the life of rubber is heat. Hence the hotter the tyre runs shorter is its life – cooler it runs, longer is its life. It is not a question of operating the tyres in “cool” condition, rather how to dissipate the heat generated quickly
By VN Ramamoorthy
It goes without saying that every user of vehicle and tyres wants to enjoy safe and optimum usage from every tyre he purchases. In case fleet operators of buses and trucks, this need forms the back bone of his operational efficiency.
So it is imperative that every end user must be aware of the factors that influence the performance and life of tyres. Before that, it is essential to recognise certain basic concepts on pneumatic tyres (Bias and Radial). Here we are focusing basically on commercial Tyres (Bias and Radial) for our discussion.
1. The major component of any tyre is Natural Rubber. There are other ingredients like Carbon Black, Steel , Nylon/ Rayon cords, Oils , Chemicals etc.
2. The worst and biggest enemy for the life of Rubber is “HEAT”. Hence the hotter the tyre runs shorter is its life – cooler it runs, longer is its life.
3. It is just common sense that tyres will get hot when they run, especially when laden with load. Heat is generated in operation due to traction, friction with road surface and mainly due to “flexing” of the side walls of the tyres in continuous running.
4. Hence it is NOT a question of operating the tyres in “cool” condition , rather how to dissipate the heat generated quickly .
5. The tyre manufacturers design the tyre and the tread portion in such a way that there are many features built in to dissipate the heat as quickly as possible.
6. But there are many factors that can be controlled by the driver / operator / Tyre maintenance / fleet manager which can ensure no unnecessary heat is generated.
1. There is a general misunderstanding that when you buy a tyre of approved quality / brand, you can simply fit the tyre , inflate it to required level and keep running it .
2. Given the pressure of operation and the need to keep the vehicles “up and running” normally the Tyre care and tyre maintenance take a back seat.
3. Some vehicle operators believe that by increasing the inflation beyond the recommended pressure prescribed by the Tyre maker , they can carry extra load.
4. Vehicle users wrongly believe that a particular tyre of specific size/ brand / type should give the same mileage / life in any application.
5. End users tend to ask the suppliers of tyres / vehicles / Retreaders to promise or warrant the mileage performance – without realizing that “Nobody knows the mileage “ except the driver / operator of the Fleet !
The performance in terms of mileage, the life span and the safety of a tyre for longer use entirely depends on the owner operator and / or the driver. There are many factors that influence or impact the performance and life of a tyre . Some are beyond the control of the vehicle owner / driver , but many are within their control !
The major factors which impede on the performance, longevity and safety of tyre can be generally classified as below:
A) Application factors
Over loading (beyond the rated load), Improper loading, Over / Under Inflation, Over speeding , Improper Dual matching of tyres ( i.e. When tyres are to be fitted in a dual position both tyres have to be matched as per set standards)
B) Vehicle factors
The good mechanical condition or lack of it , play a major part in the performance of tyres.
C) Road factors
The surface condition of the roads where the tyres are marching, obviously impact the tyres. Also the gradient , road camber , curves/ windings etc. meaning whether it is plain road or hilly terrain also have a direct impact on tyres.
D) Driving habits
Even when the vehicles and tyres are in good condition and well maintained, the roads are good and the loading and inflation are proper, if the Driver / Operator is not well trained it can impact the tyres.
There are many wrong practices and driving methods observed, especially in India which will need discussion and correction.
training of drivers is of utmost importance for ensuring better performance and life of tyres.
E) Seasonal factors
The season of fitment, Ambient temperatures of the terrain / geographical area of operation, wind velocity etc. can also have impact on Tyre performance.
In summary, it is imperative that Heat will be generated during the operations and it is equally imperative to ensure that the heat is dissipated efficiently and as quickly as possible. Only then one can get the optimum performance in terms of mileage / hours and an extended life span from tyres.
*VN Ramamoorthy is former CEO of TVS Tread, the retreading arm of TVS Group. He can be contacted via mobile 93802 94636 or by email: [email protected]
(Published in February-March 2018 issue of Tyre Asia)