Here you can get Automobile Tyre Classification and Nomenclature. Here we provide Manufacturing Process and Tyre Components ect.
Tyre is a strong, flexible rubber casing attached to the rim of a wheel. Tires provide a gripping surface for traction and serve as a cushion for the wheels of a moving vehicle. Tires are found on automobile s, trucks, buses, aircraft landing gear, tractors and other farm equipment, industrial vehicles such as forklifts, and common conveyances such as baby carriages, shopping carts, wheel chairs, bicycles, and motorcycles.
Considering the importance of tyres from the safety point of view, it’s surprising that so many motorists seem to require them more or less for granted. Many drivers fail to see their tyres often enough for pressure , damage or wear. Although tyres are developed by manufacturers to the point where they offer remarkable levels of grip on dry and wet roads and are extremely immune to punctures, their qualities are compromised if they’re under-inflated, badly worn or damaged. As these four footprints of tread are your only contact with the road, it’s vital for everyone’s safety that your tyres are in good condition.
The Manufacturing Process
A passenger car tire is manufactured by wrapping multiple layers of specially formulated rubber around a metal drum during a tire-forming machine. the different components of the tire are carried to the forming machine, where a talented assembler cuts and positions the strips to make the different parts of the tire, called a “green tyre” at this point. When a green tyre is finished, the drum collapses, allowing the tire assembler to remove the tire. The green tire is then taken to a mold for curing.
1. The first step in the tire manufacturing process is that the mixing of raw materials to form the rubber compound. Railcars deliver large quantities of natural and artificial rubber, carbon black, sulfur, and other chemicals and oils, all of which are stored until needed. Computer control systems contain various recipes and can automatically measure out specific batches of rubber and chemicals for mixing. Gigantic mixers, hanging like vertical cement mixers, stir the rubber and chemicals together in batches weighing up to 1,100 pounds.
2. Each mix is then remilled with additional heating to melt the batch and mix the chemicals. during a third step, the batch goes through a mixer again, where additional chemicals are added to make what’s known as the final mix. During all three steps of mixing, heat and friction are applied to the batch to melt the rubber and evenly distribute the chemicals. The chemical composition of every batch depends on the tire part—certain rubber formulations are used for the body, other formulas for the beads, and others for the tread.
Body, beads, and tread
3. Once a batch of rubber has been mixed, it goes through powerful rolling mills that squeeze the batch into thick sheets. These sheets are then used to make the specific parts of the tire. The tire body, for instance, consists of strips of cloth-like fabric that are covered with rubber. Each strip of rubberized fabric is used to form a layer called a ply within the tire body. A passenger car tire may have as many as four plies in the body.
4. For the beads of a tire, wire bundles are formed on a wire wrapping machine. The bundles are then formed into rings, and therefore the rings are covered with rubber.
5. The rubber for the tire tread and sidewalls travels from the batch mixer to another type of processing machine called an extruder. within the extruder, the batch is further mixed and heated and is then forced out through a die—a shaped orifice—to form a layer of rubber. Sidewall rubber is roofed with a protective plastic sheet and rolled. Tread rubber is sliced into strips and loaded into large, flat metal cases called books.
6. The rolls of sidewall rubber, the books containing tread rubber, and the racks of beads are all delivered to a skilled assembler at a tire-building machine. At the center of the machine may be a collapsible rotating drum that holds the tire parts. The tire assembler starts building a tire by wrapping the rubber-covered fabric plies of the body round the machine drum. After the ends of those plies are joined with glue, the beads are added and locked into place with additional tire body plies laid over the beads. Next, the assembler uses special power tools to shape the sides of the tire plies. Finally, the extruded rubber layers for the sidewalls and tread are glued into place, and therefore the assembled tire—the green tire—is removed from the tire-building machine.
7. A green tire is placed inside a large mold for the curing process. A tire mold is shaped like a monstrous metal clam which opens to reveal a large, flexible balloon called a bladder. The green tire is placed over the bladder and, because the clamshell mold closes, the bladder fills with steam and expands to shape the tire and force the blank tread rubber against the raised interior of the mold. During this curing process, the steam heats the green tire up to 280 degrees. Time within the mold depends on the characteristics desired within the tire.
8. After curing is complete, the tire is removed from the mold for cooling then testing. Each tire is thoroughly inspected for flaws like bubbles or voids within the rubber of the tread, sidewall, and interior of the tire. Then, the tire is placed on a test wheel, inflated, and spun. Sensors within the test wheel measure the balance of the tire and determine if the tire runs during a line . due to the design and assembly of a modern tire, rarely is one rejected. Once the tire has been inspected and run on the test wheel, it’s moved to a warehouse for distribution.
Constant improvements in rubber chemistry and tire design are creating exciting new tires that offer greater mileage and improved performance in extreme weather conditions. Manufacturers now offer tires estimated to last up to 80,000 miles. Treads, designed and tested by computer, now feature unique asymmetrical bands for improved traction and safety on wet or snowy roads.
Tire design engineers also are experimenting with non-pneumatic tires which will never go flat because they do not contain air under pressure. One such non-pneumatic tire is just one slab of thick plastic attached to the wheel rim. The plastic curves out from the rim to a point where a rubber tread is secured to the plastic for contact with the road. Such a tire offers lower rolling resistance for greater fuel economy and superior handling due to a greater area of contact between tread and road.
Classification and Nomenclature
Tyre (or tire) is a circular and ring like part of a vehicle which comes in contact with ground. Tyres are fitted on rims and are filled with compressed air. Since their invention, natural rubber is that the most widely used material in manufacturing of tyres. However, modern tyres also employ materials like synthetic rubber, fabric, steel wires, carbon black and some more compounds. Tyres find place in wide range of locomotives, from bicycles to aeroplanes.
generally , there are two major classes of tyres, according to the presence or absence of tubes in them. Thus, they are called ‘tubed tyres’ and ‘tubeless tyres’ respectively. Furthermore, based on the construction or skeleton of tyres known as carcass, tyres are classified into the following main types:
- Cross ply or bias ply: In these tyres, ply cords are at an angle of 30°-40° to the tire axis.
- Radial ply: In these tyres, ply cords run within the radial direction.
- Belted-bias ply: this is often a combination of the above mentioned types.
However, majority of the tyres used nowadays belong to the class of radial tubeless tyres.
Functions of a tyre:
- To maintain contact between vehicle and ground by providing desired traction.
- To support the load of vehicle.
- Dealing with various forces acting on vehicle during its motion.
- Providing cushion against shocks and damping them.
The components of different Types of Tyre are shown below:
Truck Bias Tyre
Radial (PCR) Tyre