轮胎工艺英语.doc

Tire Manufacturing ProcessTires are not just round and black they are sophisticated products that can take years of research and development to produce. If you have ever wondered how tires are made, the following is a roadmap for the construction of a radial tire:Start with Rubber and AdditivesTire construction starts when raw chemical additives such as sulfur, carbon black and solvents are combined with natural and synthetic rubber. The process takes place in a large machine called a banbury.In addition to mixing and grinding, the banbury heats the rubber to make it workable in preparation for further applications. The raw product emerges in the form of long, flat bands of rubber, which are then worked in rolling mills.Six Main ComponentsIt takes several machines to shape the rubber into the individual components of the tire: tread, ply, belts, beads, sidewalls, and innerliner. The tread rubber is extruded through a tuber, then measured, cooled and cut into precise lengths. Sidewalls are also extruded through tubers, along with the white rubber for a white sidewall or white lettered tire if required. The ply is produced in a calender mill, which combines thin sheets of rubber with nylon or polyester cord fabrics. The large sheets are cut to width, rolled and transported to the assembly area where all the components will come together. At the same time as the raw rubber is transformed into the tread and plies, the creel room equips the tire with its basic strength. Fine steel wire goes into the manufacture of belts for the steel-belted radial tire. Rubber from the mills and steel from the creel room are molded together into wide flat sheets, cut on the bias, rolled, and moved to the tire-building machine. The innerliner is a impermeable layer of rubber on the inside of a tire which creates a airtight chamber when fitted to the vehicle wheel. This layer eliminates the need for a innertube. The last major component of the tire is the bead. The beads are created out of wrapped steel wire, covered with rubber and formed into hoops. The bead anchors the fabric plies of the tire and seats the tire firmly on the wheel. The Green TireThe six components (tread, ply, belts, sidewalls, liner and beads) come together on the tire-building machine. These six components are assembled into what is known as an uncured, or green, tire in two stages. The carcass of the tire, including beads, plies, sidewalls and liner, is constructed on one side of the machine. The tread and the underlying belts are assembled next to the carcass on the other side of the machine. The two subassemblies are then joined together and the result is a green tire.VulcanizationThe next phase is vulcanization, the molecular transformation of the soft, gummy green tire into the tough, and longwearing, modern passenger tire. The green tire is placed in a curing mold and is subjected to intense pressure and high heat internally and externally for a specified period of time. Simultaneously, the tread pattern is imprinted onto the rubber. When it comes from the mold, the tire is ready for final finish and inspection.Final Finish and InspectionFor showroom quality, any excess rubber is trimmed off the cured tire. Every tire is thoroughly inspected. The tire then undergoes various uniformity checks to assess ride and comfort quality. Once the tires have passed all the checks and inspections, they are sent to the distribution warehouse for shipment.How To Read Tire SidewallP205/55R16 91WTire SizeExample: P205/55R16 91WPP identifies your tire as a Passenger Tire. The P stands for PMetric. If your tire size starts with LT rather than a P than it identifies the tire as a light truck tire.205205 identifies the tire section width, which is the measurement of the tire from sidewall to sidewall in millimeters. This measurement varies depending on the rim to which it is fitted.(There are 25.4 millimeters per 1 inch.)5555 is the two-figure aspect ratio. This percentage compares the tires section height with the tires section width. For example, this aspect ratio of 55 means that the tires section height is 55% of the tires section width.RR indicates the construction used within the tires casing. R stands for radial construction. B means belted bias and D stands for diagonal bias construction.1616 The last dimension listed in the size is the diameter of the wheel rim which is most often measured in inches.Load Index and Speed Rating91W91W The load index and speed rating, or service description are the numbers that follow the tire size.The load index tells you how much weight the tire can support when properly inflated. Load indices range from 74 - 150 for passenger tires with each numeric value corresponding to a certain carrying capacity. The carrying capacity for each value can be found on a load index chart. On each U.S. passenger car tire, the load limit is listed in pounds. European tires have the load limit listed in kilograms and sometimes pounds.Speed RatingsSpeed ratings are represented by letters ranging from A to Z. Each letter coincides to the maximum speed a tire can sustain under its recommended load capacity. For instance, S is equivalent to a max speed of 112 mph. Even though a tire can perform at this speed, we do not advocate exceeding legal speed limits.Speed SymbolSpeed(km/h)Speed(mph)A153A2106A3159A42012A52516A63019A73522A84025B5031C6037D6540E7043F8050G9050G9056J10062K11068L12075M13081N14087P15094Q160100R170106S180112T190118U200124H210130V240149W270168Y300186(Z)300186DOT Serial NumberThe DOT symbol certifies the tire manufacturers compliance with the U.S. Department of Transportation tire safety standards. Below is a description of the serial number. Starting with the year 2000, four numbers are used for the Date of Manufacture, first two numbers identify the week and the last two numbers identify the year of manufacture.Prior to year 2000 three numbers are used for the Date of manufacture, first two numbers identify the week and the last number identifies the year of manufacture. To identify tires manufactured in the 90s a decade symbol (a triangle on its side) is located at the end of the DOT serial number.Tire Maintenance TipsYour tires are the only part of your vehicle that actually touches the road when you drive. It only takes a couple of minutes of maintenance each month to keep your tires working at their best.Check Your Air Pressure Once a MonthIncorrect air pressure is the leading cause of tire damage. To avoid tire damage you need to check your tires air pressure once a month.The correct tire pressure is listed on the vehicle placard & can be found in the following places: The cars owner manual Inside the gas tank lid On the edge of the drivers side door On the door post The air pressure listed on the side of your tire is NOT the correct air pressure for your vehicle. That number is the maximum air pressure for the tire. Remember to check the air in your spare tire.Dont get stranded or put out costly towing expenses. Check your air pressure on your spare regularly. Note: If you have different rims than came on your vehicle originally, make sure that the bolts on your spare tire are the correct fitting.Failure to keep your tires properly inflated can increase wear and will have a negative effect on your vehicles handling.When checking and adjusting tire pressure, the following should be kept in mind: Check the air pressure when the tire is cold - tires become hot even after driving just a mile. If you must drive to add air, check your air pressure before you leave. Air pressure changes 1-2 pounds for every 10 degrees of temperature change. Air pressure goes up in warm weather and down in cold weather. Tire pressure must be the same on the tires of each axle, but may be different on the front and rear axle. Valve caps must be tightly closed to protect the valve from dust and dirt and prevent it from leaking. Replace missing valve caps without delay. Take this opportunity to inspect your tires to make sure there is nothing stuck in them or they have no deformities.Tread DepthTo prevent hydroplaning and skidding your tires must have proper tread depth. The minimum tread depth is 1/16th of and inch.Ask anyone, the easiest way to check your tread depth.the penny test. What is the penny test? Take a penny and place it in the tread of your tire. If part of Lincolns head is covered by the tread your tires have enough tread. If you can see Lincolns entire head, you should buy a new tire.You should also check your tire tread for uneven wear. Irregular wear shortens the life of your tires, if you think you have uneven wear you should take you vehicle to your tire dealer.RotationThe best way to prevent uneven wear is to have your tires rotated every 6,000 - 8,000 miles or as specified in your vehicles owner manual.Potential Tire Troubles Curbs can prove to be big trouble to your tires. Approach curbs with care, if you drive over them too fast or at the wrong angle the impact may cause the tire to crack. Avoid potholes or debris in the road when possible. Avoid fast stops & starts. Be sure to check your owners manual for your vehicles maximum load. Overloading your vehicle can shorten your tires life. Replacing Your TiresYou should replace your tires with the same type of tires that came on your vehicle original equipment. This includes tire size, type and speed rating.History of TiresThe Evolution of the Passenger TireDateline 3500 B.C.-Today man invented the greatest invention ever seen, THE WHEEL!Thousands of years later, the wheel has come a long way. For one thing it is no longer made of wood and it is guaranteed that the ride is much smoother. What hasnt changed is the fact it is still one of mans greatest inventions. Could you even imagine where we would be today without it?The early wheel was very simple.a solid curved piece of wood, then leather was eventually added to soften the ride, as time progressed it became solid rubber which led to todays tire-the pneumatic, or air inflated, radial tire.The first wheels made of metal or wood were very durable but did not provide a very comfortable ride. The nearest thing to the first tire was a metal hoop. There were many individuals that made contributions in creating the tire as we think of it today.Vulcanization and Charles GoodyearRubber was not always as useful as it is today. Early rubber did not hold shape; it would be sticky in hot weather and become inflexible in the cold.In 1839 Charles Goodyear was credited with the discovery of the vulcanization process. Vulcanization is the process of heating rubber with sulfur. This transforms sticky raw rubber to firm pliable material which makes rubber a perfect material for tires.The story of Charles Goodyear is a sad one, although he dedicated his entire life to making rubber a better form he would never profit from all his work. Charles Goodyear died bankrupt.Forty years later a rubber company would honor his hard work by using his name for their new tire company.Solid Rubber TiresSoon, after the discovery of vulcanization tires were made out of solid rubber. These tires were strong, absorbed shocks and resisted cuts and abrasions. Although they were a vast improvement, these tires were very heavy and did not provide a smooth ride.Today there are still types of tires made of solid rubber.Pneumatic TiresThe pneumatic rubber tire uses rubber and enclosed air to reduce vibration and improve traction. Robert W. Thomson, a Scottish engineer, first patented the air filled tire. Unfortunately the idea was too early for its time and was not a commercial success.In 1888 John Boyd Dunlop of Belfast, Ireland became the second inventor of the pneumatic tire. Dunlop claimed to have no knowledge of Thomsons earlier invention.The second time around the pneumatic tire caught the publics attention. The timing was perfect because bicycles were becoming extremely popular and the lighter tire provided a much better ride.Bias Ply TiresFor the next fifty years vehicle tires were made up of an inner tube that contained compressed air and an outer casing. This casing protected the inner tube and provided the tire with traction.Layers called plys reinforced the casing. The plys were made of rubberized fabric cords that were embedded in the rubber. These tires were known as bias-ply tires. They were named bias ply because the cords in a single ply run diagonally from the beads on one inner rim to the beads on the other. However, the orientation of the cords is reversed from ply to ply so that the cords crisscross each other.Today you can still find bias-ply tires as authentic equipment for antique and collector cars, as well as for certain type of off-the-road tractor tires.Radial TiresMichelin invented radial tires in 1948 and they were first introduced in Europe that year. Radial tires are so named because the ply cords radiate at a 90 degree angle from the wheel rim, and the casing is strengthened by a belt of steel fabric that runs around the circumference of the tire.Radial tire ply cords are made of nylon, rayon, or polyester. The advantages of radial tires include longer tread life, better steering and less rolling resistance, which increases gas mileage. On the other hand, radials have a harder riding quality, and are about twice as expensive to make.Tire Terminology Air Pressure Alignment of Vehicle All Season Tires ABS/Anti-Lock Brake System ASR/Anti-Slip Control Aquaplaning Balancing Bead Braking Distance Camber Casing Chains Date of Manufacture Direction of Rotation DOT Serial Number ESP/Electronic Stability Program Emergency Mobility Systems Load Index, Ply Rating or Load Range Mixing Tires Radial Tires Reinforced or XL (extra load) Tires Revolutions Per Mile (RPM) Rolling Resistance Rotation Speed Symbol Temporary Spare Tires Toe Tread Tread Depth TWI (Tread Wear Indicator) Tire Size Designation Tire Storage UTQG (Uniform Tire Quality Grading Valve Valve Cap Winter Tires Air PressureCHECK the pressure in your tires at least monthly and before long trips when your tires are cool (after the vehicle has been stopped 3 hours and then driven less than one mile). Adjust to the veh