In the world of heavy and fast commercial transport at the same time, profits are measured in kilometers and safety is determined by the safety of tires, which is undoubtedly the most vulnerable part of commercial trips in general. One of these highways is a small and highly influential enemy, namely gravel and small stones. These pebbles or small rock fragments may seem trivial to those who have no experience in this field, but they are in fact a constant and clearly expensive threat. The impact of gravel and stones on the tire grooves and the tread channels is not easy. A high-speed collision with a solid object must cause damage, but in the event of a suspension Gravel in the grooves has reached the peak of damage. This gravel, with continued pressure on it by the truck, will dig a place inside the tire tread. One of the serious effects of such a matter is the sudden explosion of the tire and premature damage to parts of the tire, as well as noise and annoying sounds.
The resulting losses are very expensive, including the cost of maintenance required for tires after being damaged by gravel stuck in the grooves, in addition to the cost of replacing seriously damaged tires, in addition to the tax of stopping the truck from working due to maintenance operations, causing a accumulation of material costs that were not in the calculations. In addition, tires that travel with a lot of stuck gravel are dangerous to the driver and other road users, as gravel may come out and fly at any time, causing injury to road mates.
In order to meet this great challenge, tire manufacturers have sought to provide technologies that expel gravel from grooves and provide high protection for tires that they may face on highways. We have developed many gravel and stone expulsion systems, the most prominent of which is (Stone Ejector Systems), which are systems to expel stones from tires, in addition to (Stone Expellers) similar to them. These techniques may seem simple in principle and the task assigned to them, but represent real progress towards road safety and reducing regular maintenance costs, as well as being a very important step in developing systems to maintain the safety of tires and the safety of trucks In this article, we will accompany you on a quick journey to learn the most important details about gravel removal systems in truck tires, while introducing you to their importance, how they work and their components. This is part of Darbek Tire Company's efforts to develop the field of knowledge among truck drivers and logistics business owners.
It is not easy to get a small stone stuck in the tire groove. It is the beginning of many bad events that affect the performance of the truck
Why are stones fatal to tires?
When we talk about gravel and stone removal techniques, it is necessary to explain the damage caused to tires, and then understand the nature of the impact of these obstacles stuck in the grooves of tires and their main channels. Next, we will talk about each of the negative effects on tires due to gravel sticking to the grooves.
First, direct mechanical damage: This damage is considered direct because it causes a cut in the tire tread, as this small stone acts as a chisel that digs deep into the tread in each wheel cycle. With the large load of heavy trucks, the damage is doubled as it presses the rubber more, constantly rubbing on the road, until the hole reaches the depth of the tread and begins to create a space for internal air to leak into the tires. In the end, the negative effect inevitably occurs because the stone is small or large, sharp or blunt, because the strong pressure with the stone attached to the depth of the tread causes a deep crack A tire explosion can cause The condition of heavy loads, even with the stone not sharp.
Second: excessive friction and accumulated heat: While the stone remains stuck in the grooves, the stone not only cuts the tire, but also creates an obstacle between the tire and the road surface, which increases the temperatures caused by friction on the road, but mainly on the place where gravel or stones are attached. By the nature of rubber, it is directly affected by heat due to its high sensitivity to heat. Therefore, the speed of oxidation increases, which results in a brittle and cracked tire due to weak chemical bonds between them within the tire vehicles. This reduces the flexibility of the tire and prevents it from performing its work as required, causing disability for drivers and fleets logistics.
Third: The destruction of the internal structure of the tire (cord): One of the most serious types of damage caused by gravel and stones stuck in the grooves and the tread channels is that gravel penetrates the cord after penetrating the tread due to constant and severe pressure, which puts a strong pressure on the cord or the internal structure of the tire, which is made of steel, nylon or polyester threads, which are completely covered by rubber. The internal structure protects the shape of the tire and maintains the normal circular shape of the tire, but in the event of damage, which is often invisible from the outside, it is considered the most catastrophic because it reduces the tire's ability to withstand weights Heavy duty, in addition to exposing the tire to a condition called “Tread Separation”. In this phenomenon, the internal structure known as Kurds separates and becomes a non-overlapping layer with the entire tire, separating the tread and shoulders from the tire. This process may occur suddenly during high speeds, which may lead to loss of control over the truck, terrible accidents and significant losses, all due to the attachment of gravel and stones.
Fourth: Imbalance and uneven wear: With stones and gravel stuck in certain grooves and not others, we have an imbalance in the tire on the asphalt surface, causing a greater imbalance in wheel rotation and truck traffic on the road. This abnormal imbalance causes loud sounds, severe vibrations and uneven wear on tires, as well as pressure on bearings, shaft, steering group and suspension systems. These composite problems all significantly reduce the life of the tire and the life of other parts related to this tire, while if we solve the problem, we would save effort, time and money and avoid Great economic waste.
Fifth: huge but indirect costs: the costs that come due to damage and negative effects on tires can be huge. The cost of replacing one truck tire may cost between 300 to 1000 US dollars, depending on the type, quality, size and brand. In fact, the real cost exceeds the price of the tire only, followed by the stopping time of the vehicle, which is called lost time, which is the time wasted waiting for the arrival of maintenance services, the time wasted in the specialized maintenance workshop, as well as the other consequences of tire problems, which are a series of problems related to the suspension system and other systems, In addition to all this collection, the costs of engineers, workers and technicians. On the other hand, you should know that damaged or problematic tires waste more fuel, which means increasing the truck's consumption of expenses on a daily basis. With these risks and costs, we should emphasize that the safety of the driver and other users of the commercial road network is a priority, as the risk of collision with vehicles is higher in the event of loss or explosion of a tire or any problem with the truck that hinders the continuation of work.
The tax of leaving stones stuck in tire grooves is not expensive! It's very expensive.
What is the technique of repelling gravel and stones in tires and what are its types?
The philosophy of stone ejection systems is based on a very simple but most effective idea, which is to prevent the stone from remaining stuck in the tire grooves in the first place, or remove it very quickly if it can enter or if it gets stuck in the grooves of the tire, rather than trying to make the tire resistant to gravel and stones, because this is very physically and mechanically impossible. The main advantage of rubber is its plasticity, flexibility and absorbency, which means that it is undoubtedly affected by stones and gravel, while gravel systems have exploited the physical and chemical forces generated automatically by the rotation of tires while they are on the road. We explain more about the technique of expelling gravel and stones in more detail.
1. The use of centrifugal force (Centrifugal Force): If the wheel rotates, it generates central thrust. This is the result of circular motion. This force is what is known as centrifugal force. Here comes its role as engineers use this force to expel gravel and stones stuck in grooves and channels by designing grooves that do not stick to gravel and stones strongly and do not let them stick strongly into the tread. It amplifies the force and focuses it on anything stuck in the grooves and channels.
2. Designing dynamic ejection lanes: The main components of these lanes or systems are a series of levers or impellers, which are made of very durable rubber or reinforced plastic, such as high-quality polyurethane compounds. These levers are strategically installed inside or on the edge of the main tire grooves (Grooves), especially in the tire shoulder area (Shoulder), as it is the area where the largest number of gravel and stones are attached. The position of the levers is accurate and mathematically calculated geometrically.
3. The shovel or boom mechanism: It is an excellent mechanical mechanism that works in the following way. When gravel enters the grooves, the tires face this crane or shovel that is installed in a correct geometric manner. As the wheel continues to rotate, the expulsion process occurs by hitting or sliding the stone on the curved surface of the shovel. Then, the stone is directed out of the groove thanks to the streamlined shape of the shovel and its sharp angle that raises the stone out, while lifting it from the base of the groove. In the end, forces combine. Centrifugal force pushes the stone out, and the force of friction with the crane or shovel helps to push the stone out With the speed of rotation of the wheel, the momentum of forces is generated, making it easier for the stone or gravel to come out quickly. It takes only a fraction of a second, which means that the stones are thrown away from the tire groove before settling at the base or end of the groove.
4. Automatic movement and pneumatic improvements: The main advantage of automatic motion systems is that they do not require external or additional power or even driver intervention, as they operate passively and the wheel continues to rotate. This system draws its power from the rotation of the wheel, making it more reliable and low in maintenance costs. Air improvements in some advanced systems take into account aerodynamics around the wheel. The design of the winch or bulldozer may help direct the flow of air in a way that slightly pulls the stone or prevents dust and water from collecting around it, which enhances the efficiency of expulsion, especially in the case of high-speed trucks.
A very simple technique is the one on which the gravel ejection system is based, but applying it in an excellent engineering manner is a giant challenge
What are the components of engineering and mechanical gravel ejection technology?
We start by knowing the parts that make up gravel and stone expulsion systems.
Motivators/levers (Ejector Pads/Levers): These pieces vary in shapes depending on the design and type of custom system. Systems installed on the main grooves, in the shoulder block, or between the block and the shoulder, and the common shapes are often such as the small shovel, the curved arm, the triangular peg or the letter “L”. The angles differ depending on the place of installation, which is two angles, the angle of attack, which represents the angle of the bulldozer's fall on the stone, and the angle of descent, both calculated with high accuracy and high engineering experience, in order to achieve the best balance between effective capture and rapid expulsion while reducing rotation resistance. Their size is small enough to accommodate the grooves and are made of durable and plastic materials Highly flexible with sufficient strength to withstand the expulsion of gravel and stones.
Installation rules (Mounting Bases): It works to achieve the function of providing a safe and strong surface sufficient to attach impellers to tires. They are often made of the same material as impellers or bulldozers, which are polyurethane or strong plastics. Their design ensures that you distribute the shear and tensile forces caused by wheel rotation and stone strikes over a larger area of the tire base, preventing the bulldozer or impellers from damage, while also containing channels that help perform the vulcanization process if the system is chemically glued by a specific glue.
Fastening and gluing system: The system is fixed to tires in a way that ensures their safety and permanent stability. One of these proven methods is the chemical fastening method, which is considered the most reliable and reliable. It is often used in original (OEM) or high-quality systems. Mechanical fastening is done through screws or nails, which are usually used in some post-installation systems or tires that cannot be fixed to them chemically (vulcanized). Small holes are drilled in the tire after the approval of the tire manufacturer or the tire manufacturer, and the system is attached to special screws or bolts with nuts and spacers (Washers). This method can be It is effective, but it is less efficient and durable than its predecessor and is a weak point in the tire because it needs to be perforated. It should only be installed by specialists and craftsmen, so as not to pose a danger.
Competence distribution patterns: Impellers and bulldozers are not installed randomly. Engineers determine the optimal pattern and number of impellers for each tire based on the tire's tread design, the angle of the grooves, the width and number of screws, in addition to the size of the tire, the expected application of the truck, the method of driving and using it. Impellers are strategically installed in areas that are most susceptible to gravel and stones, especially on the edges of the rubber blocks in the shoulders and around the intersections of the grooves.
Installation rules, fastening materials, impellers or bulldozers, and a skilled engineer, this is what you need to install gravel systems from tires
What is the benefit of gravel ejection technology in modern tires?
The impact of stone ejection systems goes beyond preventing gravel and stones from getting stuck in the grooves and channels of the tramway. Rather, their benefits reach interconnection with each other to create a comprehensive added value for logistics operations and road transport operations, starting from the following benefits:
First: extending the shelf life of tires: A gravel bulldozer can contribute to extending the life of tires between 25-50%. This benefit is the most obvious and the most measurable because we have removed the main cause of early damage. Gravel systems help tires reach their maximum life, which is determined by the environmental factors in which the truck travels. Studies and reports referred to by manufacturers strongly confirm the importance of gravel removal systems on the life of tires.
Second: reducing the rate of tire perforation: Not only reducing the possibility of puncturing tires, but even avoiding their explosion by up to 80%, by preventing stones from causing direct cutting of the tread, or spot heating due to gravel or stones stuck at the base of the grooves, which in turn leads to a sudden collapse of the tire. This means that you are not only saving the price of a used tire, but also providing invaluable protection for the safety of drivers and roadmates as a result of reducing the risk of explosion.
Third: Overall improvements: Gravel removal systems provide drivers with protection and improvements in many features, including wheel balance and road compatibility, as well as reducing fuel consumption, improving tread wear, reducing regular maintenance costs, and enhancing safety and security on commercial roads. These enhanced features are a literal translation of the direct effects that occur on the truck as a result of the installation of gravel and stone ejection systems.
Continuous developments and the future of tire protection technologies
The technology of gravel and stone expulsion systems is a continuously scalable system due to the continued development of its basic needs. Manufacturers are now looking for more advanced materials such as super polymers that combine durability, strength, ductility and high flexibility, as they are highly resistant to heat.
Work is being done to develop more high-quality and effective engineering designs by integrating mechanical techniques with each other and enhancing their effective roles, and a greater focus on providing effective sustainability steps that drivers can rely on in a more effective and long-lasting manner.
