Tyres, as an important part of the vehicle, play a vital role in its operation. And a good quality tyre must provide stable grip, smooth steering and strong braking in all road and weather conditions. As tyre technology evolves, modern tyre manufacturing has become complex. It now combines chemistry, physics, and engineering. Today’s tyre manufacturing process involves more than just rigorous raw material ratios and precise process control. In this article, Crowns Machinery will delve into each of the key stages of tyre manufacturing to help you better understand the concept of the tyre manufacturing process.
Table of Contents
The materials that make up a tyre
Tyre manufacturing relies on a wide range of carefully selected materials to meet the requirements of durability, strong grip and ageing resistance. The three main types are rubber, fillers and reinforcements. These materials are efficiently proportioned and processed to meet the demands of a wide range of driving conditions.
Rubber Natural rubber: comes from the latex of the rubber tree, and is mainly produced in tropical areas such as Malaysia and Indonesia. Because of its flexibility, natural rubber is one of the core materials in tyre construction. Synthetic rubber: petroleum-based synthetic rubbers such as styrene butadiene rubber (SBR), polybutadiene rubber (BR) and butyl rubber. These materials give tyres their unique durability and resistance to ageing. They can also be flexibly adapted to the needs of the application.
Carbon black, the filler: it gives the tyre its black colour and improves its resistance to abrasion and UV rays. It is one of the core additives in rubber compounds. Silicon dioxide: it significantly improves grip in wet conditions and reduces rolling resistance, thus improving fuel efficiency. Plasticisers and antioxidants: these additives improve the elasticity of the rubber and increase its resistance to ageing. They also make the tyre stable in harsh conditions.
Reinforcing materials textile fibres: these include rayon, nylon, polyester and aramid fibres. These materials are mainly used in the tyre’s cord ply to provide support and flexibility. Steel wires: high-strength steel wires are used in belts and beads to increase the structural strength and rigidity of the tyre, making it stable at high speeds and under heavy loads.
The main components of a tyre
A tyre is made up of several precision-engineered components. These components work together to ensure their durability, safety and handling. The following are the main components of a tyre and their functions:
Bead: The bead consists of a high-strength steel wire covered with rubber. It ensures that the tyre fits snugly on the rim, forming an airtight seal, and is a key supporting part of the tyre structure.
Steel Belt: The steel belt surrounds the tyre and provides it with additional strength and rigidity. This component, usually made of steel wire coated with brass, keeps the tyre stable at high speeds.
Cord ply: The cord ply is the skeleton part of the tyre and is made up of woven fabric layers. It gives shape and flexibility to the tyre while supporting the entire tyre structure.
Sidewall : Located between the bead and the tread, the sidewall is the thick rubber area. The sidewall provides lateral stability and protection to the tyre, reducing external impacts on the tyre.
Shoulder: The shoulder is where the tread meets the sidewall. Its design has a direct impact on the tyre’s cornering performance and stability, especially in fast corners.
Tread: The tread is the area where the tyre is in direct contact with the road, and the design and material of the tread determines the grip and wear resistance of the tyre. At the same time, high-quality tread materials need to have good elasticity and abrasion resistance.
Grooves and sipes: These are unique patterns and grooves in the tread that help the tyre to drain on slippery surfaces such as rain or snow. In addition, they increase grip.
Critical steps in tyre manufacturing
Tyre manufacturing is a complex and precise multi-step process, each step of which must be tightly controlled. This ensures the safety, durability and performance of the finished product. The following are the main key steps in tyre manufacturing:
Mixing
This is the first step in tyre manufacturing. A black rubber compound is formed by mixing up to 30 ingredients in precise proportions in a Banbury mixer. It is important to note that the homogeneity of the rubber compound during this process determines the durability and grip of the tyre. This is why the mixing ratios and temperatures need to be strictly controlled to ensure high standards.
Milling
Next, the mixed rubber is cooled and fed into the grinding machine. In the mill, the rubber compound is cut into strips in preparation for the next moulding step. At the same time, other tyre components such as the cord ply and steel belts are also coated with a layer of rubber at this stage to allow for better bonding during the next moulding process. Care needs to be taken in this process to ensure that the tyre is not only covered with rubber more evenly, but also to ensure overall structural stability.
Extrusion and calendering
In the extrusion and calendering stage, the rubber compound is extruded into specific shapes to form the tread and sidewalls of the tyre. Through the extruder, the rubber compound is made into strips of tread of a specific size and thickness, while the sidewall rubber is formed into different shapes according to the design specifications. Meanwhile, the cord ply and steel belts are formed into composite pieces by pressing the rubber compound into textile or steel cord through a calendering process. These components give the tyre extra rigidity and strength, enabling it to drive stably in a variety of road conditions. If you are looking for high quality extruders and calenders, then Crowns Machinery is the right partner.
Useful information:
Traditional calendered versus non-calendered tyre manufacturing
Advances in rubber extrusion technology for the tyre industry
Tyre moulding
After the first few steps of preparation, the tyre moulding process begins. Using a tyre moulding machine, the technician will assemble the tyre from the inside out into its initial shape. This involves components such as the innerliner, the carcass cord, the bead, the steel belts and the tread. This stage is known as ‘raw’ moulding, i.e. the uncured embryo of the tyre. It is necessary to ensure that each component is precisely positioned and aligned so that the tyre has a good structure and design.
Vulcanisation
Once the raw tyre has been moulded, it is placed in a rubber vulcanising machine, where it is vulcanised through a process of chemical reactions at high temperatures and pressures. The vulcanising machine gives the rubber its elasticity and allows the tyre to take its final shape. This process is both a transformation of the rubber’s physical properties and a shaping of the tyre’s external characteristics.
Quality checks
Before the final product reaches the market, each tyre must undergo a rigorous quality check. Firstly, a visual inspection is carried out by specialists to detect flaws and surface defects in the appearance of the tyre. Then, the internal structure is checked for compliance with standards using specialised equipment such as X-rays and homogeneity tests. Finally, the sampled tyres undergo a number of performance tests, including durability, handling and mileage, to fully assess their actual performance. This ensures the safety, durability and high quality of all finished tyres.
Conclusion
Tyre manufacturing is a promising venture as vehicles become more popular. But the process is extremely demanding, so choosing professional equipment is crucial, and at Crowns Machinery, as a rubber equipment supplier in China, we can provide professional guidance for your tyre production. In addition to this, we also offer specialist equipment to meet your tyre manufacturing needs.
These are just some of the insights we have provided into the tyre manufacturing process, which we hope you will find helpful.
