WHEELS AND CAR TYRES
The wheel is an automobile that is in direct contact with the pavement.
Its mission, in addition to bear the weight of the car, is to transmit power from the transmission in order to move the vehicle, and provide direction and adherence in moments of acceleration and deceleration.
WHEELS AND CAR TYRES
The wheels must have sufficient strength to bear the weight of the vehicle conveying the efforts and braking thrusters and oppose efforts side in a wide range of speeds and terrain conditions.
It must also comply with a series of other characteristics in order to perform its functions:
Or resistance to hold the weight of the vehicle.
Resistance or not to slip into moments of the stops.
Or capacity to absorb and cushion in large part (10%) irregularities in the terrain.
Or resistance to wear.
Facility or to dissipate heat produced during braking and as a result of their adherence.
Light weight or reducing the effects of inertia and the weight is not suspended.
Or cross-resistance to the effects of drift.
Or Visually and ease of mounting and dismantling its coupling.
Elements of the wheel
The whole of the wheel comprising two distinct elements, the metal part, the tire.
• Part metal
The metallic elements is formed:
Or wheel.
Or Disco.
Or cube (on the wheels of wire or radio).
Tire
It is the metal part of the wheel, through an appropriate profile, supports the tire and allows the union to the same hub of the vehicle through the hard parts or coupling.
The main feature of the tires is their profile, which is cross-sectional. It is essential to consider:
Or Tab. This is the area where laterally supports the stub of the deck.
Seat or heel. It is the surface of the tire that rely on the heels of the cover.
Or Base. Corresponding to the surface of the rim between two seats heel.
Hole or output valve. The rim presents a drill that allows the valve assembly where Excel.
Normally the rim to the disk, forming a single unit and joins in different ways.
Types of tires
From basis or Honda.
Or Desmontables: semihonda or flat.
Terminology dimensional tires
Width or
It is measured in inches. It is the altitude profile falling between two vertices, formed by the seats of heel and eyelashes.
Nominal diameter or
It is measured in inches. It is the equivalent to the difference of seats heel measure theoretically, in any of the above points.
Tires are defined by their profile and its diameter.
Disk
The wheel disc can be distinguished, mainly, the following functional areas:
Surface or support is the flat surface of the disc which should match on the corresponding hub of the vehicle.
Or fixing holes are those that allow the passage of fixing bolts.
Or central hole (to the wheels that possess): The hole is practiced in the center of the disc towards saving the hub of the hub.
Window or valve is opening practiced on the disc to provide access to the valve inflated when necessary. Some tires have two diametrically opposed windows, which facilitates the balanced wheel, while expected to double access to the mounting twin.
Windows or ventilation: are those practiced in the disk to facilitate the cooling of the drum or disc brakes.
The types of wheels which are manufactured at present are:
Wheels or disk steel stamping. They are rigid, resistant to shocks and relatively light and easy to produce in large quantities.
They are the most widely used at present.
Wheels or disk light alloy. The holes for the passage of asparagus fixing, have a tapered seat for the proper focus of the wheel.
They can be of different types:
– Conventional. B – No windows. — Cancel.
Types of union between disc and rim
The union between the disc and the rim can be:
– For arc welding.
B – rivets.
– For welds by points.
D – embuticiones.
Light alloy wheels
By introducing a lower weight, compared with the steel, aluminium and magnesium alloys, allowing greater thicknesses thereby increasing rigidity, and the distribution of tension takes place on its wider area.
In this type of wheel, the rim can be wider, allowing the assembly of large tyres section.
Given that such material is a good conductor of heat, the cooling of the brakes and tyres is better than on the wheels of steel. But they are very sensitive to salt and corrosion-type electrolyte.
Steel wheels with spokes
They are very light wheels at the same time of great strength. His job is almost certain restricted to vehicles or sports competition.
All the effort to which the wheels are transmitted from the rim to the hub via their radios whose tensile strength is much greater than the compression. Because of the little resistance they offer flexibility, radios separately should intertwine with the aim of achieving adequate strength.
Because the radios are fixed to the wheel rim by nuts, and will not be achieved thereby sealing properly, can not tires mounted on them without camera.
Its manufacturing cost is very high. The wheel is fitted on the shaft through the grooves of the mangueta and cube the wheel through a palomilla.
• Party pneumatic
It is the party that is mounted on the rim. It’s in direct contact with the ground. It is a ring of rubber padding air, in addition to providing the required bond with the pavement, serves as a buffer against irregularities marring.
It consists of three main elements:
O The chamber, which is cylindrical in shape, soft rubber, inflatable and that stands between the rim and the outside (cover).
O The cover, which is the outside, which then devote more detailed study.
Or The Shield, which is located between the rim and the camera. Do not carry all the wheels.
Tyres camera
They are the ones who cover the rim and form a partnership with the chamber, ensuring that the seal. The camera takes incorporated valve. They called tube-type.
This does not allow a tire rim without camera. The Shield does not allow the camera come into contact with the rim.
Tyres without camera
0
It is now used tires without chamber, which removes this element because of the increased tightness offering, the remaining air between the deck and the rim. They called tubeless.
The main advantage of tyres without camera is that before a puncture the air is lost rather slowly, allowing movement for a few kilometres, while in the camera equipped with air is lost instantly. Other advantages are: reduced risk of bursting, no rust on the inside of the rim, there are no air pockets between the camera cover, and reduced weight of the package.
It has the disadvantage of the tightness, as any deformation of the rim allows for the loss of air.
The watertight closure is achieved through a highly impermeable layer of rubber into the air bearing inner adherence to the deck.
The cover has to be mounted on a special rim. Pack an appropriate valve, mounted in a hole in the same practiced.
Covers
1
The structure of the cover and its component elements are similar in all of them.
They are formed by the parties set forth in 1.
Casing
It is the part of the tire that its structure gives flexibility and resilience, and puts up efforts. It is formed by overlapping layers of tissue with ropes stickers and cross one another to give strength to all.
Belt or layers rolling
Installed between the tread and casing and is aimed at the tire does not deform, too, rolling through the area.
Banda rolling
It is the contact zone between the ground and the vehicle is the area of greatest wear on the wheel. It consists of a thick layer of rubber, which is practised sculpture tire, which allows both the grip of the vehicle as the evacuation of water for them.
Shoulder
It is the extreme lateral ends where the tread. This is where it generates the greatest temperature of the tire.
Flanks
It is the lateral sides of the cover. They are subjected to constant efforts (and bending load). They are the ones who are deformed because of the irregularities of the terrain.
Heels
They are the binding site of the cover to the rim. They are accommodated steel rings usually ensures that the attachment to the rim.
A layer of hard rubber
Whatever type of cover, is coated internally by a layer of hard rubber vulcanized.
Types of covered
According to the architecture and arrangement of layers or tarps that form the shell cover, or the use or non-belt. Manufactured at present three types of shells, which give the following names to the cover:
• Covers diagonal or conventional.
• Covers cinturadas diagonals.
• Radial Tires.
Covers diagonal or conventional
2
The cabinet consists of several tarps that cross each other, heel to heel, and is formed by layers of strings textiles or steel wires, which form an angle of 30 ° to 40 ° with respect to the axis of the circumference of the deck, and between layers angles of 60 ° to 90 °.
One of the most important characteristics are the angles that form the threads, as they determine their resistance, directional stability and discomfort while driving.
Disadvantages. When filming occurs:
One or deformation of the surface of contact with the pavement.
One or wear faster warming.
A bond or less.
Fuel consumption or higher.
At present almost not used.
Cover Diagonal vložkom
Also called reinforced deck. It combines the structure of the deck with a diagonal belts or belt, which makes improve its characteristics. At present it is not widespread use.
Cover radio
3
On this deck, the casing or shell, is composed of several layers of textile or steel wires which are directed towards the radius of a heel to another, forming the backbone of the circumference of the casing at an angle of 90 degrees.
Among the tread and casing are placed several layers that form the belt. The strings that form the belt form an angle of about 20 º, with the shaft. This stabilizes the top or waist top of the casing.
Advantages:
It reduces or deformation of the surface of contact with the pavement.
There is no displacement or between tarpaulins of the case.
Improved performance or kilometre.
Improved or adherence.
Or Better stability.
Decrease or fuel consumption.
Increased comfort or because of its flexibility.
Decrease or heating and tire wear.
Materials decks
The main materials used in their manufacture are:
O The natural or synthetic rubber. The natural clotting is obtained from latex, the synthetic is a product obtained from hydrocarbons.
O The black smoke to achieve:
? The characteristic black.
? Increased resistance to the pressure.
? Mayor elasticity.
The sulfur or to facilitate vulcanized.
Or cables, made from rayon, polyester, fibreglass and steel.
• Election tire
If we consider the functions tire on the vehicle, which occur simultaneously, which are:
Support or cargo.
Beam engine or effort.
Or directing the vehicle.
Participate in or stability.
Or participate in the suspension.
Or participate in the braking and on the other hand its application to different areas and times of the year, the tire is very difficult to achieve this ideal, we can say that there is.
We must choose the ideal type of structure, sculpture, and tire pressure as a function of:
O The vehicle.
Or use.
Or speed.
Time or shooting.
For all these reasons, manufacturers make a range of products, according to the conditions of use, to achieve:
The adhesion or tire.
Or directional stability.
Or comfort of the march.
The tire wear or slow and smooth.
O The rolling resistance.
Good drainage and little or noisy.
Manufacturers, in their catalogs, they recommend the best type of tire must be used depending on all the circumstances and factors involved in each specific case.
Types of assembling the wheels
According to its assembly, are divided into two groups:
Or Simple. When a wheel is mounted at each end of the axis of rotation. It is often used in the front axle trucks.
Or Twin. When two wheels are mounted at each end of the axis of rotation. This is the kind of assembly that is seldom used in the rear axle trucks and buses, supporting approximately double burden that the front axle.
Tires that mate must meet the following requirements:
Being in the same or dimension
Inflados or at the same pressure.
If possible, or from the same brand, type and have the same degree of wear.
O A maximum tolerance for pairing in the lines of 0.5%.
Or Colocarse always larger diameter wheel on the outside of the pairing.
The valve
The valve is the tire that allows filling the air, control or retention and drainage.
Its assembly can be:
In tires, or with cameras.
In tires or without cameras.
Tyres special
These tires have required a special design in their manufacture for the purpose of achieving higher speeds and an increase in security.
• Tyres camera with multiple air (Kleber)
The structure of this tire is radial and lacks the air chamber normal, which in this case is divided into three compartments, each with its corresponding valve.
It is adaptable to all types of commercial tires. It is not necessary spare wheel, while maintaining stability in the event of a puncture.
• Tyres Denobo
This tire does not bring a camera. The tread pattern is broad and narrow flanks. Under normal conditions is more effective than a radial tire.
In case of a puncture, when you start deflating, it automatically seals the puncture through a liquid that carries internally, avoiding overheating of the tire. In this case you can take a tour of 160 km. At a speed of 80 km. / H.
• Tire Drop Center
The Drop Center is a pneumatic tire without camera and its use is for trucks and buses.
It is best refrigerated tyres classics, having a surface slightly above them.
• Tyres Super Single
This type of tire is no camera. Their relationship is so between 50 and 70.
Replaces in some cases, the twin wheels because of its:
Or Simplicity.
Good or cargo distribution.
Minor or weight.
Minor or rolling resistance.
Homologation
All tires must, for their manufacture, meet the specifications and standards set out in the Regulations for Certification for Tires No. 30 and No. 54.
Example: the approval mark 9 E – 002430 indicates that the tire considered has been approved in Spain with the number 002430.
Nomenclature
The Rules for Certification relate data corresponding to the identification of the tire. These data must be printed on the tire sidewall and respond to the specific characteristics of the tire.
At 1 describes the figures, letters and signs marking a cover for tourism Michelin.
– “Bib” notes the location of the wear indicator.
– The trademark.
C – tire width: 185 mm.
– Series tire: 70. The number 70 indicates that the height of the deck h is approximately equal to 70% of its width g. In other words: h = 0.7
– Its structure is radial g
F – Bore: 14 inches (corresponds to the diameter of the rim).
G – Tire without camera (Tubeless).
H – Load Index: 88 (560 kg).
– Index of speed.
J – Trademark.
K – Type.
• Marcajes those covered truck
Example: 315 / 80 R 22.5 154 / 149 L REGROVABLE – Tubeless
Bring marked on the annotation 154 / 149 means that the burden.
Loads 154 (index for simple assembly)
149 (Index mount twin)
The annotation regrovable means that this tire is scheduled to be reesculturada the tread, where it has been worn.
• Structure
If the cover is or radial, contained an R.
O If the cover is diagonally vložkom see a Biasbel Ted.
If the deck or diagonal is not provided sign.
• Terms of use
Index speed represents the maximum recommended speed for the vehicle. There are many indexes, which can be distinguished S (up to 180 km / h), F (between 180 and 210 km / h) and V (over 210 km / h).
Index load index or table of charges represents an index, which is tabulated. In this table we reflects the number of pounds that it is incumbent upon each tire (Eg: 88 index, up to 560 kg).
Uses in snow: a sign contained S.M or S + M. (Recall that the S = snow means snow in English).
• With or without camera
If the tire or bring a camera, no symbol.
If the tire or not bring a camera, contained the word tubeless.
• Date of Manufacture
A box contains 3 or 4 digits. The first two indicate the week of the year that was manufactured and the last or last two digits, the decade that was manufactured.
• Wear Indicator
For security reasons, do not wait until the tyres are plain to replace them. The tires have wear indicators, as manifested by the appearance of bands smooth cross when the depth of the drawing has been reduced to 1.6 mm.
This device is intended to draw attention to the tire wear and be able to monitor its progression.
Recauchutado
It consists of replacing the rubber of the tread, all ply the waist or any part thereof.
Only those can be retreaded tyres having the housing in good condition.
They are repairs that are not always desirable conduct.
Employment chains
When atmospheric conditions cause the appearance of snow or ice on the asphalt, the adhesion of the tyres is reduced significantly, causing a major constraint on the ability of traction. Under these conditions, to guarantee the motor, put chains covering the circumference of the casing transversely to the direction of rotation of the same as a regular distances. That allows the string “bite” on snow and ice, providing enough motor for progress.
The channels must always placed in the driving axle, ie, in the front, vehicles with traction on the front and rear of the drive back, due to the heavy demands that cause the tread. The speed of the vehicle must be moderate and at the time that the sea ice or snow disappears, should be withdrawn.
If the conditions are not too extreme, a good alternative to the chains are so-called winter tires. Its main feature is in the tread, which provides a range of mobile flake rubber that nail in the snow a few millimeters and enable greater capacity for adhesion longitudinal. When circulating in dry, for its own configuration lamellae are sharpen due to attrition calculated by the manufacturer and that leaves them ready for its next use in snow. The disadvantage of these tires is the most wear and less able to move at high speed, so their use should be limited to the winter season.
Another type of tyre available in the tread of some steel nails, with rounded tips, especially on the cover about 2 mm.
Main factors affecting the security and performance of the tyres
The tyres have a certain load capacity. As a general rule should not be surpassed.
A tire overloaded by 20%, loses 30% of its performance.
• Low inflation (4 – A)
Filming with low inflation is the cause of most of the damaged tire: abnormal wear, warping, segrevanjem, etc..
A low inflation of 20%, causing a reduction in the yield of 30% or so.
• On inflation (4 – B)
Excessive pressure decreases adherence favors skating and risks of cuts, causing excessive fatigue of the tire casing.
• Ambient Temperature
The wear of the tyres depends to a large extent on the ambient temperature during the shooting.
• Speed Shooting
Influences considerably in the rapid wear of the tires.
A tire is worn twice as fast at 120 km. / H. To 70 Km. / H.
• Clashes
Clashes against curbs on the sidewalks, the move to high speed on potholes, rocks or other obstacles, they can cause damage to the tire, but its consequences are not always appear at the time.
• Driving Style
A sporty driving on winding roads, with sharp acceleration and braking frequently, which creates tensions and diminish considerably in a very variable performance of the tyres.
As a guideline we can say that, generally, if a type of shooting creates greater fuel consumption or faster wear on the brakes at the same time also causes a higher consumption of tyres.
• Verification and inflation pressures
Correct inflation – Security.
– Save fuel.
– Duration of the covers.
– Comfort
The inflation pressure should be checked regularly.
• Check the pressure when tires are cold
In a tourism means tire cold who has not shot an hour before at least, or having shot 2 or 3 km. At low speeds.
In light trucks means tire cold when there is no road for hours.
It is normal that the pressure increase during the shooting.
If spell check the pressure after a certain distance (tires hot), take into account that to be correct, must be higher 0’3 kg / cm. The recommended cold.
Later, when possible, we need to put the appropriate pressure with cold tires.
• Do not ever deflate tyres hot
Not ovidar properly inflate the spare wheel.
• Monitoring of the tyres during the shooting
Some tires are well-maintained security and a good performance kilometre.
• Monitoring of the status of roofing and wheels
The condition of the tyres should be checked regularly:
Or cuts, cracks, tears, tarpaulins apparent, and so on. In the tread or on the flank, may make it necessary to replace or repair.
Verify equally or the state of the wheels and valves, especially in the assemblies without camera.
• Monitoring how to wear decks
The wear, abnormally fast or irregular, indicating an abnormal use of pneumatic or mechanical maladjustment. For example:
O A mismatch of parallelism in the wheels of the front axle or in some cases in the rear, causing abnormal wear and fast.
The gaps or too important bearing or direction, causing irregular wear.
The brakes or poorly regulated wear can cause localized or rising from one point to another of the tread.
A fall exaggerated positive or negative, can cause wear that affects only a portion of the tread.
Keeping the wheels
The rim should be kept always well balanced. This is done by placing the outer or inner part, as appropriate, some of lead counterweights that prevent vibrations caused by the difference in mass along the perimeter.
It should be especially careful when cleaning after driving on roads embarrados, since pegotes mud attached to the rim can unbalance the rim and produce strong vibrations. We must also take precautions to park, avoiding flick tires with curbs, which could loosen counterweights balancing.
As regards to tyres, the main care should focus on inflation pressures, based on those recommended by the manufacturer and adecuándolas the burden. Never put pressure on different tires mounted on the same shaft.
We must also pay attention to the depth of the drawing, noting that it should not be less than 1.6 mm. Across its surface.
When wear occurs on both sides of the tread, the cause is an insufficient pressure. If on the contrary occurs in the central area, is due to excessive pressure.
To change tires, it should:
Or Make tires in a better state, or new, on the rear axle.
O The change in position between wheels, not vary side. Change front / rear without crossing right / left.
In the event of a puncture or burst, the driver can always try to control the vehicle by the management. Therefore it is preferable to bring the best wheels behind, to try to reduce the potential for damage to the axis on which we can not act directly.