A tire or ban is a ring-shaped component that surrounds the wheels to transfer vehicle loads from the wheel axle through the wheels to soil and provide traction on the surface traversed. Most tires, such as for cars and bicycles, are pneumatically pumped structures, which also provide flexible bearings that absorb shock when the tires rotate over rough features on the surface. The tires provide a trace designed to adjust the weight of the vehicle with the strength of the rolled surface bearings by providing a pressure bearing that will not damage the surface excessively.
The materials of modern pneumatic tires are synthetic rubber, natural rubber, cloth and wire, along with carbon black and other chemical compounds. They consist of tread and body. The footprint provides traction while the body provides a container for a certain amount of compressed air. Before the rubber was developed, the first version of the tire was just a metal band mounted around the wooden wheel to prevent wear and tear. Early rubber tires are solid (not pneumatic). Pneumatic tires are used in many types of vehicles, including cars, bicycles, motorcycles, buses, trucks, heavy equipment, and airplanes. Metal tires are still used in locomotives and wagons, and solid rubber tires (or other polymers) are still used in a variety of non-automotive applications, such as some castors, carts, lawn mowers, and wheelbarrows.
Video Tire
Etymology and spelling
The word tire is a short form of clothing , from the idea that wheels with tires are dressed wheels.
The spelling of tires did not appear until the 1840s when Britain began to shrink the wheels of rail cars fitted with soft iron. Nevertheless, traditional publishers continue to use tires . The Times in the UK was still using tires until the end of 1905. Spelling tires began to be commonly used in the 19th century for pneumatic tires. in England. The 1911 edition of the EncyclopÃÆ'Â|dia Britannica states that "[t] he spelled the 'tire' is not now accepted by the best British authority, and is not known in the US", while Fowler's use of modern English on 1926 says that "nothing can be said for 'tires', which are etymologically wrong, and need not be different from our own [sc] English] & older US usage today." However, during the 20th century, tires became established as a standard English spelling. Maps Tire
History
The earliest tires were leather straps, then iron (then steel) placed on wooden wheels used on wagons and carts. The tires will be heated in a forge fire, placed on wheels and extinguished, causing the metal to contract and fit in the wheel. A skilled worker, known as a wheel-maker, does this work.
The first patent for what appears to be a standard pneumatic tire appeared in 1847 put forward by Scottish inventor Robert William Thomson. However, this never goes into production. The first practical pneumatic tires were made in 1888 at May Street, Belfast, by Scottish-born John Boyd Dunlop, owner of one of Ireland's most prosperous vet practices. This was an attempt to prevent his 10-year-old son's headache, Johnnie, while riding his three-wheeled bicycle on a rough sidewalk. His doctor, John, then Sir John Fagan, has set the bike as an exercise for the boy, and is a regular visitor. Fagan participates in designing the first pneumatic tire. Cyclist Willie Hume demonstrated the supremacy of Dunlop tires in 1889, winning the first race of tires in Ireland and then England. In the Dunlop tire patent specification dated 31 October 1888, his interest is only used in cycles and light vehicles. In September 1890, he was made aware of previous developments but the company kept the information to himself.
In 1892, the Dunlop patent was declared invalid due to previous artwork by a forgotten companion, Scot Robert William Thomson of London (London patent 1845, France 1846, United States 1847), though Dunlop is credited with "the awareness of rubber can withstand wear and tire while maintaining its durability ". John Boyd Dunlop and Harvey du Cros together work through the next big difficulty. They employ the inventor Charles Kingston Welch and also acquire other rights and patents that allow them to have limited protection for their Pneumatic Tire business positions. Pneumatic tires will be Dunlop Rubber and Dunlop Tyres. The development of this technology depended on a myriad of engineering advances, including the vulcanization of natural rubber by Charles Goodyear in the United States and independently by Thomas Hancock in England, and patented by each separately in 1844, as well as by the development of "Clincher" "Rims for holding the tire in place laterally at the edge of the wheel.
Synthetic rubber was found in Bayer's laboratory in the 1920s. In 1946, Michelin developed a radial tire construction method. Michelin had bought the Citroen car company bankruptcy in 1934, so he could soon adjust this new technology. Due to its superiority in handling and fuel economy, the use of this technology is rapidly spreading across Europe and Asia. In the US, the outdated bias-ply tire construction survives, with a market share of 87% by the end of 1967. Delays caused by tire manufacturers and automakers in America are "concerned about transition costs." In 1968, Consumer Reports, an influential American magazine, recognized the superiority of radial construction, triggering a rapid decline in Michelin's competitor technology. Even in the US, radial tires now have a 100% market share in cars.
Currently, more than 1 billion tires are produced annually in more than 400 tire factories (see List of tire companies).
Wheel support
There are 2 aspects of how pneumatic tires support the wheel rims in which they are installed. First, the tension on the string pulls on the uniform bead around the wheel, except where it is reduced above the contact patch. Second, the bead transfers the total power to the rim.
The air pressure, through the ply cord, gives a force around the bead around the rim wheel on which the tire is fitted, pulling out in a 360-degree pattern. Thus the bead must have high tensile strength. Without any force applied to the outer tread, the bead is pulled equally in all directions, so no additional force is applied to the tire bead and wheel rim. However, when the footprint is pushed in on one side, it releases some tension in the side wall corresponding to the pulled bead. But the side wall on the other hand keeps pulling the bead in the opposite direction. Thus the fully tensioned side wall pulls the tire and wheel rim in the same direction as the displacement of the tread with the same force as applied to push the tread inside.
This side wall fence to be a stress support is a big reason for older tire coil tire construction using materials available at the beginning of the 19th century. The arrangement of cross-ply cables directs the cable to more directly support the bead & amp; wheel rims (such as sling: bead for rope and under tread back to opposite beads, both ways, so traversing the rope). However, with better combinations of cables, beads, rims, and manufacturing techniques, combined with the focus and ongoing research on tire efficiency and durability, it is feasible and desirable to produce radial-layered cable tires, which, for many applications ( although higher costs), outperform and more of a drastic longer life (reliability-normal-service-life/cost ratio) of cross-ply cable tire design similar to (a) facilitate flat contact patterns with evenly distributed pressure across the area momentary stationary contact between tread & amp; soil and (b) lower operating costs over time: due to reduced tire temperature, decreased rolling resistance, lower puncture rate, longer life length, etc.
Manufacturing
Pneumatic tires are manufactured in around 450 tire plants worldwide. Tire production begins with bulk materials such as rubber (60% -70% synthetic), black carbon, and chemicals and produces many special components that are assembled and cured. Many types of rubber are used, the most common are styrene-butadiene copolymers. The Tire Manufacturing article describes the components that are assembled to make tires, a variety of materials used, manufacturing and machinery processes, and overall business model.
In 2004, $ 80 billion of tires sold worldwide, in 2010 was $ 140 billion (about 34% growth adjusted for inflation), and is expected to grow to $ 258 billion per year by 2019. By 2015, the US produces nearly 170 million tires.. More than 2.5 billion tires are produced each year, making the tire industry the main consumer of natural rubber. It is estimated that by 2019, 3 billion tires will be sold globally every year.
In 2011, three top tire manufacturing companies based on revenue were Bridgestone (producing 190 million tires), Michelin (184 million), Goodyear (181 million); they were followed by Continental, and Pirelli. The Lego Group produced more than 318 million toy tires in 2011 and is recognized by Guinness World Records as the tire manufacturer with the highest annual production by any manufacturer.
Materials
Modern pneumatic tire materials can be divided into two groups, the cables that form the layers and elastomers that wrap them.
Cable
The rope, which forms ply and bead and provides the tensile strength required to withstand inflationary pressures, may consist of steel, natural fibers such as cotton or silk, or synthetic fibers such as nylon or kevlar.
Elastomer
The elastomers, which form the tread and wrap the wires to protect them from abrasion and hold them in place, are a major component of the pneumatic tire design. Can consist of a variety of rubber material compositions - the most common are styrene-butadiene copolymers - with other chemical compounds such as silica and carbon black.
Swipe resistance
Optimizing rolling resistance in elastomeric materials is a key challenge for reducing fuel consumption in the transport sector. It is estimated that passenger vehicles consume about 5 ~ 15% of their fuel to overcome rolling resistance, while estimates are considered higher for large trucks. However, there is a trade-off between rolling resistance and wet traction and grip: while low rolling resistance can be achieved by reducing viscoelastic properties of low tangent (?) Compounds, it comes with wet traction and grip costs, requiring hysteresis and dissipation energy (high tangent (?)). The low tangent (?) Value at 60 ° C is used as a low rolling resistance indicator, while the high tangent (?) Value at 0 ° C is used as a high indicator of wet attractiveness. Designing elastomer material that can achieve high wet traction and low rolling resistance is key in achieving fuel safety and efficiency in the transportation sector.
The most commonly used elastomer material today is styrene-butadiene copolymers. It combines butadiene, which is a highly rubberized polymer ( Tg = -100Ã, Â ° C) that has low hysteresis and thus offers good rolling resistance, with styrene, which is a highly glassy polymer > Tg = 100 Â ° C) which has high hysteresis and therefore offers good wet grip properties in addition to wear resistance. Therefore, the ratio of the two polymers in the styrene-butadiene copolymer is considered key in determining the glass transition temperature of the material, which correlates with the grip and resistance properties.
Material science research efforts are underway to improve the properties of these elastomers. For example, this involves the modification of a micro-copolymer (for example, using a butadiene rubber styrene solution (S-SBR) to control the addition of a vinyl butadiene unit as well as a polymer macro structure (such as wide-molecular weight distribution (MWD).) The present investigation also involves viewing elastomeric functionalization via addition of fillers such as silica and carbon black, as well as other nano-filler tests such as nanocellulose crystals, carbon nanotubes, and graphene.
Trialkoxymercaptoalkyl-silan is a class of silane bonding agents that offer advantages in reducing rolling resistance and volatile substance emissions.
Components
Tire wreck consists of several parts: tread, beads, side walls, shoulders, and ply.
Tread
The tread is part of the tire that tangent to the road surface. The part that comes into contact with the road at that moment is the contact patch. Tread is a thick rubber, or rubber/composite compound that is formulated to provide the right level of traction that is not quickly lost. The tread pattern is characterized by geometric shapes of grooves, lugs, voids and sipes. The groove runs circularly around the tires, and is needed to channel water. Lug is part of the tread design that touches the road surface. Void is the space between the lugs that allows the lugs to flex and empty the water. The tread pattern has non-symmetrical (or non uniform) lug sizes in a circle to minimize noise levels at discrete frequencies. Sipes is a slit tire cut, usually perpendicular to the groove, which allows water from the grooves to escape to the side in an attempt to prevent hydroplaning.
Treads are often designed to meet the marketing position of a particular product. High performance tires have a small void ratio to provide more rubber contact with the road for higher traction, but can be exacerbated by a softer rubber that provides better traction, but is used quickly. Mud and snow (M & amp; S) tires are designed with higher void ratios to deliver rain and mud, while providing better gripping performance.
Lug footprint
The lugs tread provides the contact surfaces needed to provide traction. When the lug treads enter the street contact area, or the footprints, it is compressed. Because it rotates through the site, it changes circularly. Upon exiting the trail, it recovers to its original form. During the deformation and recovery cycle, the tire provides variable power into the vehicle. These forces are described as Variations of Force.
Tread cancel
The void tread provides space for the lug to flex and damage when entering and leaving the track. The voids also provide channels for rainwater, mud and snow to distribute away from the site. The vacancy ratio is the empty area of ​​the tire divided by the entire area of ​​the site. Low vacuum areas have high contact areas and therefore higher traction on clean and dry sidewalks.
Rainfall
The rain flow is a design element of the tread pattern that is specifically set to channel water away from the trail. Rain stream is circular in most truck tires. Many high performance passenger tires feature a sloping rain channel from the center toward the tire side. Some tire manufacturers claim that their tread pattern is designed to actively pump water out from beneath the tire by a flexible tread action. This results in smoother rides in different types of weather.
Sipes
Tread lugs often feature slit - sipes - which increases the lug's flexibility to damage as it crosses the tread area. This reduces the shear stress in the lug and reduces the heat that accumulates. Inhaled and eliminated tire testing equals a measurable increase in snow traction and ice braking performance, but reduces and extends the braking distance on wet and dry sidewalks with a few feet above the sucked tires. Fans of off-road tires have been inhaling tires for years for greater appeal, as many manufacturers are now offering already inhaling off-road tires.
Wear bar
The measuring rod (or wear indicator) is a feature located at the bottom of the tread groove indicating that the tire has reached its wear limit. When the tread lugs are worn to the point of wear rod connected in the lugs, the tire is completely worn out and must be removed from the service. Most of the bars used indicate the remaining 1.6 millimeter (0.063 inch) tread depth and the tires are considered "worn" when the tread is worn up to that point.
Bead
The bead tire is the part of the tire that connects the rim to the wheel. The beads are usually reinforced with steel wire and widened with high strength, low flexibility rubber. The seat bench is firmly attached to two rims on the wheel to ensure that tubeless tires withstand air without leaks. Match bead tight to ensure the tire does not shift in a circle when the wheel spins. The width of the rim in conjunction with the tire is a factor in the handling characteristics of the car, since the rim supports the tire profile.
Sidewall
The side wall is the tire part that bridges the tread and the bead. The side walls are mostly made of rubber but reinforced with cloth or steel ropes that provide tensile strength and flexibility. The sidewall contains the air pressure and transmits the torque applied by the drive shift to the footprint to create traction but supports little vehicle weight, as is clear from the total collapse of the tire when punctured. Side walls are made with factory-specific details, government-mandated warning labels, and other consumer information, and sometimes decorative ornaments, such as blackboards or tires.
Shoulders
The shoulders are part of the tire on the edge of the tread when making the transition to the side wall.
Ply
The layers are relatively insoluble rope layers embedded in rubber to retain their shape by preventing the rubber from stretching in response to internal pressure. The orientation of the layers plays a large role in tire performance and is one of the main ways tires are categorized.
Related components
Some additional components may be needed other than just tires to form functional wheels.
Wheel
Tires attached to the wheels most often have an integral rim on the outside edge to hold the tire. Automotive wheels are usually made of pressed and welded steel, or a combination of light metal alloys, such as aluminum or magnesium. This alloy wheels can be cast or forged. The assembled wheels and wheel are then bolted to the vehicle hub. The decorative hubcap and trim ring can be placed on wheels.
Rim
Beads of tires are held at the edges, or "outer edges" of wheels. This outer edge is formed to get the right shape on each side, having a sloped inner cylinder radial wall where the tire can be mounted. Wheel rims should have the right design and type to withstand exact sized tires. The tires are mounted on wheels by forcing the beads into channels formed by the inner and outer wheel rims.
Tubes in
Most bicycle tires, many motorcycle tires, and many tires for large vehicles such as buses, heavy trucks, and tractors are designed for use with deep bumps. The inner tube is a torus-shaped balloon made of waterproof material, such as soft and elastic synthetic rubber, to prevent air leakage. The inner tube is inserted into the tire and blown to maintain air pressure.
Large inner tubes, large inflatable tori, can be reused for other purposes, such as swimming and rafting (see swimming ring), tubing (recreation), sledding, and twitching. Directly made blowing tios are also manufactured for this use, offering a choice of colors, fabric covers, handles, decks, and other accessories, and removes a prominent stem valve.
Valve stem
The valve rod is a tube made of metal or rubber, where the tire is pumped, with valves, usually Schrader valves in cars and most bicycle tires, or Presta valves on high-performance bikes. The valve stem usually protrudes through the wheels for easy access. They mount directly to the rim, in the case of tubeless tires, or are an integral part of the inner tube. The rubber in the valve stem is eventually degraded, and, in the case of tubeless tires, regular valve stem replacement or with tire replacement reduces the likelihood of failure. Some may notice that their valve stems are all metal with nuts retaining it (as opposed to a typical rubber rod with brass yarn). Most modern passenger vehicles are now required to have a tire pressure monitoring system that usually consists of valve sticks attached to the electronic module. The module is hidden inside and only visible when the tire has been removed from the wheel.
Type of construction
Radial tire technology is now the standard design for all automotive tires, but other methods have been used.
Bias
The tire bias (or cross-layer) construction uses a body ply strap that extends diagonally from the bead to the bead, usually at an angle in the 30 to 40 degree range, with successive layers placed in the opposite corner forming a cross pattern to where the footprint was applied. The design allows the entire body of the tire to flex easily, providing the main advantage of this construction, smooth ride on rough surfaces. These bearing characteristics also cause major drawbacks of bias tires: increasing rolling resistance and less control and traction at higher speeds. This outdated technology is still made in limited quantities to supply collector vehicles. It is possible to pair older cars with modern tires if historical authenticity is unimportant.
Biased
A biased bonded belt begins with two or more bias-layers in which the stabilizer belt is tied directly below the tread. This construction provides a smoother ride that is similar to a bias tire, while reducing rolling resistance because the belt increases the rigidity of the tread. The design was introduced by Armstrong, while Goodyear made it popular with "Poliglas" brand tires featuring polyester carcasses with a fiberglass belt. The "bonded" tire initiates two major layers of polyester, rayon, or nylon annealed as in conventional tires, and then placed on top is a circular belt at different angles that improves performance compared to non-belted bias tires. The belt may be fiberglass or steel. This technology is temporary, not found here stop-gap, introduced by US manufacturers to prevent radial tires. Radial
Radial tire construction uses a ply body cable extending from the beads and across the tread so that the rope is mounted at approximately right angles to the centerline of the tread, and parallel to each other, and the stabilizer belt directly below the tread. The belt can be either cable or steel. The advantages of this construction include longer footprint life, better steering control, less bursts, better fuel economy, and lower rolling resistance. The disadvantages of radial tires are louder journeys at low speed on rough roads and in off-roading contexts, decreased ability to "cleanse" and lower grip abilities at lower speeds.
After the 1968 Consumer Reports announcement of radial design excellence, radials embarked on non-negotiable climbing in market share, reaching 100% of the North American market in the 1980s.
Tubeless
Tubeless tubes are pneumatic tires that do not require separate inner tubes.
Semi-pneumatic
The semi-pneumatic tires have a hollow center, but are not pressurized. They are lightweight, low cost, puncture proof, and provide bearings. These tires often come as a complete assembly with wheels and even integral ball bearings. They are used on lawn mowers, wheelchairs, and wheelbarrows. They can also be rough, usually used in industrial applications, and are designed to not pull their rim in use.
Hollow but not pressurized tires have also been designed for automotive use, such as Tweel (portmanteau tires and wheels), which is an experimental tire design being developed at Michelin. The outer casing is rubbery like an ordinary radial tire, but the inside has a special compressible polyurethane spring to support a comfortable ride. In addition to the horizontal impossibility, the tires are intended to combine the comforts offered by high-profile tires (with high sidewalls) with resistance to the cornering styles offered by low-profile tires. They have not been shipped for wide market use.
No Air
Solid
Many tires are used in non-pneumatic industrial and commercial applications, and are manufactured from solid rubber and plastic compounds through printing operations. Solid tires include those used for lawn mowers, skateboards, golf carts, scooters, and many types of light industrial vehicles, wagons, and trailers. One of the most common applications for solid tires is for material handling equipment (forklifts). The tires are mounted by means of a hydraulic tire press.
Metal
Specifications
Tire pressure monitoring system
The tire pressure monitoring system (TPMS) is an electronic system that monitors the tire pressure on individual wheels on the vehicle, and notifies the driver when the pressure falls below the warning limit. There are several types of designs to monitor tire pressure. Some actually measure air pressure, and some make indirect measurements, such as measuring when the relative sizes of the tires change due to lower air pressure.
Inflation pressure
Tires are determined by vehicle manufacturers with recommended inflation pressure, which enables safe operation in the rated ratings and loading of specified vehicles. Most tires are stamped with a maximum pressure rating. For passenger vehicles and light trucks, the tire should be pumped as recommended by the vehicle manufacturer, usually located on stickers inside the driver's door or in the vehicle owner's handbook. Tires generally should not be pumped into pressure on the sidewall; this is the maximum pressure, not the recommended pressure.
The inflated tires naturally lose pressure over time. Not all tire-to-rim seals, seal valve-stem-to-rim, and valve seals are perfect. Furthermore, the tires are not fully airtight, and so the pressure loss over time naturally due to the diffusion of molecules through the rubber . Some drivers and shops inflate tires with nitrogen (typically 95% purity) instead of atmospheric air, which is already 78% nitrogen, in an effort to keep the tire at an appropriate longer inflation pressure. The effectiveness of the use of nitrogen vs. air as a means to reduce the level of unfounded pressure loss, and has proven to be a false marketing deception. One study noted a difference of 1.3 psi (9.0 kPa; 0,090 bar) (from initial pressure of 30 psi (210 kPa; 2,1 bar)) for air-filled tires. nitrogen. The test showed an average loss of 2.2 psi (15 kPa) for a tire containing nitrogen compared to 3.5 psi (24 kPa) for air-filled tires. However, statistical significance of the test was not given because no reported t -test or p values ​​were reported. And they noted that a good loss of a nitrogen-filled tire and an air-filled tire meant that tire pressure should be checked regularly.
The tire contact patch is easily altered by over- and underinflation. Overinflation can increase wear and tear on the central contact patch, and underinflation will cause a concave tread, resulting in fewer central contacts, although the overall contact patch will remain larger. Most modern tires will be used evenly at high tire pressures, but will decline prematurely if lack of air. Increased tire pressure can reduce rolling resistance, and may also result in shorter stopping distances. If the tire pressure is too low, the tire contact patch will greatly increase. This improves rolling resistance, tire flexing, and friction between road and tire. Lack of inflation can lead to overheated tires, premature wear and tread, and site separation in severe cases.
Load rating
Tires are determined by the manufacturer with maximum payload ratings. Expenses that exceed ratings can lead to unsafe conditions that may cause steering instability and even rupture. For the rankings table, see the ban code.
Ranking speed
The speed rating indicates the maximum speed at which the tire is designed to operate. For passenger vehicles, these ratings range from 160 to 300 km/h (99.4 to 186 mph). For speed ranking table, see the tire code.
Service ratings
Tires (especially in the US) are often rated service, mainly used on bus and truck tires. Some rank for long term, and some for multi-dot type stop-start work. Tires designed to run 500 miles (800 km) or more per day carrying heavy loads require special specifications.
Treadwear rating
Ranking treadwear or treadwear grade is how long tire manufacturers expect tires to last. A Course Monitoring Tire (standard tires to be compared to test tires) has a "100" rating. If the manufacturer gives treadwear 200 ratings to new tires, they indicate that they expect the new tire to have a useful life of 200% of the Tire Monitor Course life. "Test tires" are all dependent on the factory. A Brand 500's rating will not necessarily offer the same mileage driver as a Brand B tire with the same rating. Testing is unregulated and can vary greatly. The Treadwear rating is only useful for comparing the whole range of brand A to itself. Wear tread, also known as tire wear, is caused by friction between the tire and the road surface. Government legal standards establish the minimum permissible site footprint for safe operation.
Rotation
Tires can exhibit irregular wear patterns after they are mounted on the vehicle and some wear out. Front-wheel drive vehicles tend to use the front tire at a greater level than the rear tires. Tire rotation moves the tire to different car positions, like front-to-back, for even out wear, with the aim of extending the life of the tires.
Wheel alignment
When mounted in a vehicle, wheels and tires may not align with the direction of travel, and therefore may show irregular wear. If the differences in large alignment, the irregular wear will be substantial if left uncorrected.
Wheel alignment is a procedure to check and correct this condition by adjusting camber, caster and toe angles. Angular adjustments should be made to OEM specifications.
Retread
A fully-worn tire can be reproduced to replace a worn footprint. This is known as retreads or recapitulation, a process of rubbing old treads and applying new footprints. Venturing is economical for truck tires because the replacement cost of the tread is less than the price of new tires. Vehicle retread tires are less economical because of high retread costs compared to the cheap new tire prices, but are favorable compared to high-end brands.
The tires used can be retreated by two methods, molds or heat and pre-cure or cold healing methods. The method of healing the mold involves the application of raw rubber to the previously prepared and polished casing, which is then cured in the matrix. During the curing period, vulcanization takes place and the bonds of raw rubber to the casing, take the shape of the tread of the matrix. On the other hand, the pre-healing method involves the application of a ready-made tread on a polished and prepared casing, which is then cured in an autoclave so that vulcanization can occur.
During the retreading process, the retreading technician must ensure the casing is in the best possible condition to minimize the possibility of casing failure. Cases with problems such as restricted footprint, tread separation, irreversible pieces, rusted belts or side wall damage, or tires that are bolted or depressed, will be rejected.
In most situations, the retreaded tire can be moved in the same condition and at the same speed as the new tire without loss of safety or comfort. The percentage of vulcanized failures should be almost the same as the failure of new tires, but many drivers, including truck drivers, are guilty of not maintaining proper air pressure regularly, and, if the tires are abused (overloaded, oxygen deprived, or mismatched) to other tires on one set of duals), then the tire (new or recap) will fail.
Many commercial trucking companies place retreading only on trailers, using only new tires on their steering and steering wheels. This procedure increases the driver's chances of maintaining control if there is a problem with the tire being retreaded.
Performance characteristics
The interaction of tires with sidewalks is a very complex phenomenon. Many details are modeled in the Pacejka Magic Formula. Some are described below.
Balance
When the wheels and tires rotate, they exert centrifugal force on the shaft that depends on their central mass location and their moment orientation of inertia. This is called balance, imbalance, or imbalance. Tires are checked at the point of manufacture for excessive static imbalances and dynamic imbalances using automatic tire balance machines. The tires are checked again at the car assembly plant or the tire retail store after installing the tires to the wheels. Assembles that exhibit an excessive imbalance are corrected by applying a balance to the wheel to counter the tire/wheel imbalance.
To facilitate proper balancing, most high-performance tire manufacturers place red and yellow marks on the sidewall to allow the best possible installation of tire tires. There are two methods of tire mounting with high performance for wheels using red marks (uniformity) or yellow (heavy).
Camber thrust
Camber thrust and camber force is a force generated perpendicular to the direction of a rolling tire travel due to limited camber angles and contact patches.
Centrifugal growth
Tires that rotate at higher speed tend to develop larger diameters, due to the centrifugal force that forces the rubber tread away from the axis of rotation. This can cause a speedometer error. As the tire's diameter grows, the width of the tire decreases. This centrifugal growth can cause tire friction to the vehicle at high speed. Motorcycle tires are often designed with reinforcements that aim to minimize centrifugal growth.
Power circle
Style circles, traction circles, friction circles, or frictional ellipses are a useful way to think of dynamic interactions between vehicle tires and road surfaces.
Patch contact
The contact patch, or footprint, of the tire, is the area of ​​the site that is in contact with the road surface. This area transmits the power between the tire and the road through friction. The long-to-wide ratio of the contact placente affects steering behavior and cornering.
Corner strength
The cornering force or side force is a lateral force (ie parallel to the road surface) generated by vehicle tires when cornering.
Dry traction
Dry traction is a measure of the tire's ability to provide traction, or grip, in dry conditions. Dry traction is a function of rubber adhesion.
Style variations
Element tread treads and side walls are deformed and restored as they enter and exit the trail. Because of its elastomeric rubber, it undergoes deformation during this cycle. When the rubber changes shape and recovers, it instills cyclical force into the vehicle. This variation is collectively referred to as tire uniformity. Tire uniformity is characterized by radial force variation (RFV), lateral force variation (LFV) and tangential style variation. Radial and lateral force variations are measured on the force variation machine at the end of the manufacturing process. Ban beyond the limits specified for RFV and LFV is rejected. Geometric parameters, including radial runouts, lateral runouts, and side wall bulges, were measured using a tire uniformity machine at the tire plant at the end of the manufacturing process as a quality check. In the late 1990s, Hunter Engineering introduced the GSP9700 Road Force balancer, which was fitted with a load roller similar to a stylish variation engine used in the factory to improve tire uniformity. This machine can find the best position for the tire on the given wheel so that the over-all assemblies are round as possible.
Load sensitivity
Load sensitivity is the behavior of tires under load. Conventional pneumatic tires do not behave like classical friction theory would suggest. Namely, the tire load sensitivity is most apparent in their typical operating range such that the friction coefficient decreases as the vertical load, Fz, increases.
Pneumatic trail
The pneumatic tire footprint is a trace-like effect produced by a compliant tire that rolls on a hard surface and is subject to side loads, as in turn. More technically, it is the distance that the resultant force of the side-slip occurs behind the geometric center of the contact patch.
Length of relaxed
The length of relaxation is the delay between when the slip angle is introduced and when the cornering force reaches its steady-state value.
Swipe resistance
Rolling resistance is resistance to rolling caused by tire deformation in contact with road surface. As the tire rolls up, the tread enters the contact area and changes flat to adjust to the highway. The energy needed to make deformation depends on the inflation pressure, the rotating speed, and many physical properties of the tire structure, such as spring strength and stiffness. Tire makers are looking for lower scroll resistance tire construction to improve fuel economy in cars and especially trucks, where rolling resistance accounts for a high proportion of fuel consumption.
Pneumatic tires also have much lower rolling resistance than solid tires. Because the internal air pressure acts in all directions, the pneumatic tire is able to "absorb" the mound on the road as it rolls over it without experiencing a reaction force opposite to the direction of travel, as does the solid (or foam-filled) tires. The difference between the rolling resistance of pneumatic and solid tires is very easy to sense when pushing a wheelchair or stroller equipped with both types provided the terrain has significant roughness in relation to wheel diameter.
Auto alignment tics
The self-aligning torque, also known as the alignment torque, SAT or Mz, is the torque created by the tires when rolling over which tends to direct it, which rotates it around its vertical axis.
Angle Slip
Sudut tergelincir atau sudut ketukan adalah sudut antara arah perjalanan roda bergulir sebenarnya dan arah ke arah yang mengarah (yaitu, sudut jumlah vektor roda kecepatan translasi dan kecepatan deretan ).
Kurs musim semi
Vertical stiffness, or spring rate, is the ratio of the vertical force to the vertical deflection of the tire, and contributes to the overall vehicle suspension performance. In general, the spring rate increases with inflationary pressures.
Stopping distance
Performance-oriented tires have a tread pattern and rubber compound designed to grasp the road surface, and usually have a slightly shorter stopping distance. However, special braking tests are required for data outside of generalizations.
Workload
Tire workloads are monitored so as not to be depressed, which can lead to premature failure. Workload is measured in Ton Kilometer Per Hour (TKPH). The name and unit of measurement are the same. The recent shortage and increasing cost of tires for heavy equipment have made TKPH an important parameter in tire selection and equipment maintenance for the mining industry. For this reason, tire manufacturers for large earth moving vehicles and mining assign TKPH ratings to their tires based on their size, construction, type of footprint, and rubber compound. The rating is based on the weight and speed the tires can handle without overheating and causing it to deteriorate prematurely. The equivalent size used in the United States is Ton Mile Per Hour (TMPH).
Use footprint
There are several types of abnormal tread wear. Poor wheel alignment can cause excessive wear of the deepest or outermost ribs. Gravel roads, rocky terrain, and other rough terrain cause accelerated wear. Over-inflation above the maximum side wall can cause excessive wear to the center of the site. Modern tires have steel belts built to prevent this. Under-inflation causes excessive wear to the outer ribs. An unbalanced wheel can cause uneven tire wear, because rotation may not be perfectly circular. Tire manufacturers and car companies have a common set of standards for site wear testing that includes measurement parameters for site loss profiles, lug counts, and heel-toes. See also Workload above.
Wet traction
Wet traction is the grip or tire grip in wet conditions. Wet traction is enhanced by the design ability of the tread to deliver water out of the tire tread and reduce hydroplaning. However, tires with circular cross-section, such as those found on race bikes, when inflation right has a footprint small enough not to be susceptible to hydroplaning. For such tires, it appears that a completely slippery tire will provide superior traction on wet and dry pavement.
Alerts
DOT Code
The DOT code is a sequence of alphanumeric characters formed into the tire wall and allows tire identification and age. This code is mandated by the US Department of Transportation but is used worldwide.
The DOT code begins with the letter "DOT" followed by the factory code (two digits or letters) representing the manufacturing plant. The last four figures represent the week and year of the tire built. The three-digit code is used for tires manufactured before 2000. For example, 178 means produced at the 17th week of the 8th year of the decade. In this case means 1988. For tires manufactured in the 1990s, the same code applies, but there is a small triangle (?) After the DOT code. So, the tires produced at the 17th week of 1998 will have the code 178 ?. In 2000, the code was redirected to a 4-digit code. The same rule applies, so for example, 3003 means the tire was manufactured at the 30th week of 2003.
The other number is the marketing code used at the manufacturer's discretion. DOT codes are also useful in identifying tires in case of product withdrawal.
E-mark
All tires sold for street use in Europe after July 1997 must carry the E mark. The mark itself is an uppercase "E" or a lowercase "e" - followed by a number in a circle or rectangle, followed by the next number. An "E" indicates that the tire is certified to meet ECE 30's dimension, performance and marking requirements. A (e) "e" indicates that the tire is certified to comply with the dimensions, performance and marking requirements Directive 92/23/EEC. Figures in circles or rectangles indicate the country code of the government given consent type. The last number outside the circle or rectangle is the type of type approval certificate issued for a particular size and type of tire.
Print serial number
The tire manufacturer typically embeds the serial number of the mold onto the side wall area of ​​the mold, so the tire, once printed, can be traced back to the original manufacturer's mold.
Size Code
Car tires are depicted with alphanumeric code, which is generally formed into the tire wall. This code sets the tire dimension, and some key constraints, such as load-bearing ability, and maximum speed. Sometimes the inner wall contains information that is not included on the outer wall, and vice versa.
The code has evolved in complexity over the years, as seen from a mix of metric and English units, and ad-hoc extensions to letters and numbering schemes. New automotive tires often have ratings for attractiveness, treadwear, and temperature resistance (collectively known as Uniform Tires Quality rating (UTQG)).
Most tire sizes are provided using an ISO Metric measurement system. However, some pickup trucks and SUVs use Light Truck Numeric or Light Truck High Flotation systems.
Vehicle app
Tires are classified into several standard types, based on the type of vehicle they serve. Because manufacturing processes, raw materials, and equipment vary according to the type of tires, tire manufacturers typically specialize in one or more types of tires. In most markets, factories that produce radial passenger and truck tires are separate and different from those that make aircraft tires or off-the-road (OTR).
Passenger vehicles and light trucks
High performance
High performance tires are designed for use at higher speeds, and more often, more "sporty" driving styles. They have a softer rubber compound to increase traction, especially at high cornering speeds. This softer rubber trade has a shorter life span.
High-performance road tires sometimes sacrifice wet weather handling with shallower drains to provide a more actual rubber surface area for dry weather performance. The ability to deliver high performance levels on wet and dry pavements varies greatly among producers, and even among tire models from the same manufacturer. It is an active field of research and development, as well as marketing.
Winter tire
Mud and Snow, (or M S, or M & S), are tires for all seasons and winters designed to provide better traction on snow and ice, compared to summer tires. These tires have a more aggressive footprint along at least one end of the tire, which is designed to touch the snowy surface.
Special winter tires will bear "Mountain/Snowflake Pictograph" if designated as winter/snow tires by American Society for Testing & amp; Material. Winter tires will usually also bring MS, M & amp; S, or MUD AND SNOW words (but see All-season tires, below).
Some winter tires are made to allow the optional insertion of metal buttons (consisting of tungsten carbide or other hardwood pins embedded in a softer metal base) for additional traction on ice-covered roads.
The use of buttons is limited in some countries due to the increasing wear and tear of roads, with the exception of most Nordic and North American jurisdictions, where they are commonly used in colder areas during the winter. Norway has imposed a tire-usage fee in some urban areas, and there are several roads in some major cities in Sweden where buttons are not allowed. In America, buttons are usually never used on heavier vehicles (except for some emergency vehicles such as ambulances and fire engines.), But stud tires for heavy vehicles are common in Scandinavia. Resurfacers also use studded tires. Upper-grade racing and rally classes mandate vehicles equipped with studded tires.
Other winter tires depend on factors other than studding for traction in the ice, for example the highly porous or hydrophilic rubber attached to the wet film on the ice surface. The best unclothed winter tires offer a grip close to the studded tires during most of the winter conditions, with the exception of ice blanks or polished ice, where they can not match the performance of the studded tires. The reason is that winter tires do not rely on imbalances on the surface of the ice because the sipes are to be taken, while the buttons cut the smoothest ice surface (and in the process also makes it uneven).
The studded tires are also used on the bike, and the grip advantage on the ice is similar to that of traction sand, with the difference that there is no risk of empty spots when using a studded tire. Quality tire manufacturers use buttons with hard center pins as well for bicycle tires, and like their fellow automakers, the buttons will continue to stand out from the tires even after years of use on the bare sidewalks. There are also low quality studded bike tires that have buttons that do not have a hard-metal center pin (there are still middle pins, but not hard metal). Such students can wear out within a few weeks of cycling on dry sidewalks.
Some jurisdictions may require snow tires or tire chains on vehicles driven in certain areas during extreme weather conditions.
Mud tire
Mud tires are special tires with large tread patterns and thickness designed to bite muddy surfaces. The large open design also allows mud to clear quickly from among the lugs. The muddy field tires also tend to be wider than other tires, to spread the weight of the vehicle over a larger area to prevent the vehicle from sinking too deep into the mud. However, in sufficient quantities of mud and snow, the tire should be thinner. Being thinner, the tire will have more pressure on the road surface, allowing the tire to penetrate the snow layer and gripping the harder snow or the road surface beneath it. This does not offset when the snow is too deep for such penetration, where the vehicle will sink into the snow and plow the snow in front and eventually pack it underneath until the wheel no longer has appeal. In this case, wider tires are preferred, as they have larger contact patches and are better able to 'float' over mud or snow.
All seasons
The All Season tire classification is an intermediate compromise developed for use on dry and wet roads during the summer and developed for use in winter conditions. The type of rubber and tread pattern most suitable for use under summer conditions can not, for technical reasons, provide a good performance on snow and ice. All-season tires are a compromise, and not a very good summer tire or a very good winter tire. They have, however, become ubiquitous as original equipment and replacements on cars marketed in the United States, due to their convenience and adequate performance in most situations. Even so, in other parts of the world, like Germany, it is common to have tires set for winter and summer. All-Season tires are also marked for mud and snow just like winter tires but rarely with snowflakes. Due to a compromise with performance during the summer, winter performance is usually worse than winter tires.
All-terrain
All-terrain tires are usually used on SUVs and light trucks. These tires often have sturdier side walls for greater durability against punctures while traveling off-road, tread patterns offer wider distances than all-season tires to remove mud from the tread. Many tires in the all-terrain category are designed primarily for on-road use, especially all-terrain tires that were initially sold with vehicles.
Spare
Some vehicles carry spare tires, which are mounted on wheels, for use in the case of flat tires or bursts. Minispare, or "space saving" tires are smaller than regular tires to save on luggage/luggage space, mileage, weight, and cost. Minispares have short life expectancy and low speed ratings, often below 60 miles per hour (97 km/h).
Light snapshot
Domestic trailers (including trailer for camping) for use on public highways often have tires that are different from those seen on cars. Often they are more obedient than radial tires, and they often do not have an aggressive tread pattern like standard road tires. They are not built for high traction in most cases, because in many cases it is not essential that the trailer tire has good traction as the vehicle pulls the trailer.
Run-flat
Several innovative designs have been introduced that allow tires to run safely without air for limited ranges with limited speed. These tires usually have strong side walls and support loads. Another approach is an additional support structure mounted on the rim inside the pneumatic tire that will hold the load in case of deflation.
The disadvantage is that many run-flat tires can not be repaired in case of a puncture. This is because the manufacturer informs the auto industry that the state where the side wall can not be determined is due to the compacted rubber wall. Some brands may allow one fix for a flat tire, while others do not allow it.
Heavy duty truck
Heavy duty tires are also referred to as Truck/Bus tires. This is the size of tires used on vehicles such as commercial trucking, dump trucks, and passenger buses. Truck tires are categorized into specialties according to vehicle position such as steering, axle drive, and trailer. Each type is designed with reinforcements, material compounds, and tread patterns that best optimize tire performance. A relatively new concept is the use of "Super Singles" or Wide Singles. Generally in multiple configurations, there are 2 tires per position, each between 275 mm - 295 mm in width. The Super Single replaces this with a single tire, usually 455 mm wide. This allows fewer footprints to touch the ground and also removes 2 side walls per position. Along with the weight savings of 91 kilograms (200 pounds) per axle, this allows the vehicle to use this to improve fuel economy.
Off-the-road
Off-the-road (OTR) tires include all non-running tires on public roads, such as installed in construction vehicles (wheel loaders, backhoe, graders, trenchers), on planes, in mining vehicles, in forest machines. OTR tires can be either biased or radial construction even though the industry is likely to lead to increased radial usage. OTR Tires Bias is built with a large number of reinforcing layers to withstand heavy and high load service conditions.
Dramatically increasing commodity prices has led to a shortage of new tires. As a result, trucks worth millions of dollars can be grounded due to a lack of tires, which cost millions of dollars in lost productivity. This has led to a stronger effort to recycle old OTR tires. In 2008, the new OTR tires could cost up to $ 50,000; Retread tires are sold half the price of new tires, and last 80% during that time. Retreading OTR tires is labor-intensive. First, the retreading technician must place the old tire into the buffing machine to remove any residual footprint; "Skiving" follows this, which is the disappearance, by hand, from the buffing misses. Next, the technician should check the tire, fix the defects. Finally, the technician fills a hole in the tire with rubber, uses cement rubber adhesive, and places the tire on the machine that will apply the new tread.
Agricultural and off-road flotation tires
The classification of agricultural tires includes tires used on agricultural vehicles, usually tractors and special vehicles such as harvesters. The driven wheels have very deep and wide lugs to allow the tire to hold the ground easily.
For off-road driving in passenger vehicles, such as in mud, sand, or heavy snow, typically used high-capacity tires. Flotation tires are not the same as M S tires, as these tires are designed for low speed and full-time off-road use rather than muddy and snow-covered roads. Flotation tires also help traction in swampy environments and where soil compaction is of concern, featuring large footprints at low inflation pressures to spread out areas where rubber meets the ground. Knobby Tires are especially useful where the soil consists of loose particles that can be moved by knobs. Although low pressure increases traction in many types of terrain, adjustments may be necessary for hard surfaces such as paved and asphalted roads. Vehicles using flotation tires for rock climbing are susceptible to flat tires where tires appear from the rim, breaking the "beads".
Racing
The racing tires are very special according to the condition of the vehicle and the race track. This classification includes tires for drag racing, Auto-x, drifting, Time Attack, Road Racing Ã, - as well as large market racing tires for Formula One, IndyCar, NASCAR, V8 Supercars, WRC, MotoGP and the like. Tires are engineered specifically for specific race tracks according to surface conditions, loads of cornering, and track temperatures. Racing tires are often engineered for minimum weight targets, so tires for the 500 mile (800 km) race can run only 100 miles (160 km) before the tires are replaced. Some tire makers invest heavily in racing tire development as part of corporate marketing strategies and advertising tools to attract customers. The racing tires used in the tarmac stage are called slick. When the driver's wet road will use an intermediate slick and when the road is dry, a soft slick is used. Racing tires are often illegal for regular toll road use.
Industrial
Industry tire classification is a bit of all-catching category and includes both pneumatic and non-pneumatic tires for specialized industries and construction equipment such as skid loaders and forklift trucks.
Bicycle
Source of the article : Wikipedia
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