Tyres are the only components that come into contact with the ground during driving. They may seem unremarkable and are often dirty, but poor maintenance can often be a potential hidden danger for accidents.
As the ancients said, “Read ten thousand books and travel ten thousand miles.” Siiski, many car owners don’t have such a poetic and leisurely mood. Long-distance travels and living on the road are just commonplace for them and an indispensable part of life.
Tyre Blowout
The service life of tyres is actually a rather ambiguous concept. For some tyres, it can be as short as 50,000 – 60,000 kilometers, while for others, it can reach up to 200,000 kilometers. Truck tyres are the epitome of hard work and endurance, shouldering heavy burdens. For experienced drivers, tyres, as the “feet” of a truck, can traverse stony mountain roads, roll over hard ice surfaces, and even pass through scorching deserts. Nevertheless, they also have their own “Achilles’ heel” – the sidewall.
During daily driving, 80% of tyre problems originate from the sidewall. Compared with the tread, the scarred sidewall is not only thinner but also lacks sufficient steel wires for adhesion, making it rather fragile.
Currently, in order to carry more cargo and gain more economic benefits, many overloaded trucks in China still choose tubeless radial steel wire tyres. Moreover, to achieve greater load-bearing capacity, they usually inflate the tyres with 2 – 4 more atmospheres of pressure.
When the actual load of a truck exceeds the maximum allowable load of the wheels, the internal pressure of the tyre will increase. When the internal pressure of the tyre exceeds the sealing pressure of the tyre valve, air leakage will occur. If one of the rear dual tyres, which have a large load-bearing capacity, leaks air and the driver fails to notice it in time, it will cause the other tyre in the rear dual-tyre setup to bear excessive load and eventually blow out.
In the modern transportation industry, the issue of overloading is more complex than it seems. With the increasing demand for goods transportation, some companies are under great pressure to cut costs and maximize profits. This has led to the prevalence of overloading practices. Besides the direct impact on tyres, overloading also affects the overall performance and safety of the vehicle. The suspension system, for example, has to bear more weight than it was designed for, which can accelerate its wear and tear. The braking system also faces challenges, as it needs to stop a heavier vehicle, increasing the braking distance and the risk of accidents. And the engine has to work harder, consuming more fuel and potentially leading to premature failures.
Overinflation, on the other hand, is often a result of misinformation or negligence. Some drivers may not be aware of the proper inflation pressure for their tyres, relying on rough estimates or incorrect advice. In fact, tyre manufacturers clearly specify the recommended inflation pressure based on factors such as the vehicle type, load, and driving conditions. Incorrect inflation not only increases the risk of blowouts but also affects the handling and fuel efficiency of the vehicle. When a tyre is overinflated, the contact area with the road surface decreases, reducing the traction, especially in wet or slippery conditions.
After long-term use of the brakes, the brake drums will gradually reach high temperatures. Since the truck tyre valves are close to the middle position of the inner side of the tyre rim, very near to the brake drums, the high temperature generated by the brake drums can cause the rubber at the bottom of the valve to expand, deteriorate, and thus have poor sealing performance. Trucks that often drive in mountainous or hilly areas have to use the brakes for long periods frequently, so the sealing performance of their tyre valves is generally poor, and the probability of tyre blowouts is higher.
The relationship between braking and tyre blowouts is an area that has seen continuous research. High-performance braking systems, such as those with larger brake discs and more efficient calipers, can generate even more heat during intense braking. This heat not only affects the tyres but also other components in the vicinity. Modern trucks are starting to incorporate heat shields and improved ventilation systems around the brakes to reduce the heat transfer to the tyres. Lisaks, new materials for tyre valves are being developed. These materials can withstand higher temperatures without significant expansion or degradation, improving the overall reliability of the tyre under harsh braking conditions.
When a tyre has internal damage, it means that the inner tube of the tyre has been punctured by a sharp object or has had a valve air leak and has been repaired. The sealing performance and load-bearing capacity of a repaired tyre are far inferior to those of an unrepaired one.
When repairing a tyre, a rubber gasket is usually placed at the inner tube repair site. The function of this gasket is to repair the puncture in the outer tyre and prevent the repaired tyre from “bulging” at the puncture site of the outer tyre. Siiski, this gasket, which protrudes from the inner surface of the outer tyre, has an abrasive effect on the inner tube repair site under load. If the vehicle often drives under overloaded conditions or encounters bumpy roads, it is very easy for the tyre to blow out.
The repair technology for tyres has also been evolving. Traditional patch repairs are being replaced by more advanced techniques, such as hot vulcanization repairs. Hot vulcanization can create a more seamless bond between the repair material and the tyre structure, improving the strength and durability of the repaired area. Siiski, even with these advanced repair methods, a repaired tyre still has certain limitations. It is crucial for drivers and fleet managers to understand these limitations and make proper decisions regarding tyre usage, especially for high-risk applications like long-haul trucking.
4. Cooling Tyres with Cold Water Is Not Advisable; Sudden Temperature Changes Can Cause Blowouts
After long continuous high-speed driving, tyres will heat up. If the heat cannot be dissipated in time, the tyre temperature will rise. An excessively high temperature rise (above 95 °C) may lead to tyre delamination and eventually tyre bursting.
The thermal management of tyres is a key aspect of vehicle safety. In addition to avoiding cold water cooling, proper driving habits can also help maintain a reasonable tyre temperature. Näiteks, taking regular breaks during long trips allows the tyres to cool down naturally. Some advanced vehicles are now equipped with tyre temperature monitoring systems that can alert the driver when the tyre temperature approaches a dangerous level. These systems use sensors embedded in the tyres to measure the temperature accurately and transmit the data to the vehicle’s dashboard or a connected mobile device.
5. Damaged Tyres Should Be Replaced Promptly to Avoid Friction and Heat Generation
For rear double-axle models and semi-trailer models, due to the large number of tyres, it is not easy to notice a blown tyre. If the vehicle continues to drive, the damaged tyre will rub against the intact tyres, generating heat until another tyre also blows out. After a double-tyre blowout, the wheel hubs will come into contact with the ground, generating a large amount of sparks, which can then ignite the damaged tyre.
In large fleets, proper tyre management becomes even more crucial. Regular tyre inspections should be carried out, not only to check for visible damage but also to monitor the overall condition of the tyres, including tread depth and pressure. Fleet managers can use advanced tyre management software to keep track of each tyre’s history, from installation to any repairs or replacements. This data-driven approach can help predict potential tyre failures and ensure that damaged tyres are replaced in a timely manner, reducing the risk of multiple tyre blowouts and the associated safety hazards.
As the automotive industry advances, new tyre technologies are emerging to address these blowout issues. Run-flat tyres, for example, are designed to allow the vehicle to continue driving for a certain distance even after a puncture, reducing the immediate danger of a sudden blowout. Self-sealing tyres can automatically seal small punctures, preventing air leakage. These new technologies, along with improved manufacturing processes and materials, aim to make driving safer by minimizing the occurrence of tyre blowouts. Lisaks, research on smart tyres is underway. Smart tyres can communicate with the vehicle’s control system, providing real-time data on tyre conditions, allowing for more proactive safety measures and optimized driving performance.
