MILEAGE IN THE MAKING - STORY OF TUBELESS TIRE

tires the tires on your car truck tires airplane tires tractor tires our precision built by skilled craftsmen from the same basic raw materials let's take a look at them this is a piece of natural rubber this is one of the synthetic rubbers each of the various types of rubber has certain desirable qualities and they are mixed together according to precise formulas developed for each particular type of tire or parts of a tire here is the cord used to make the plies the fabric body or carcass of a tire high tensile steel wire is used for the core of the beads the parts of a tire that go onto the rim of the wheel oil is used to soften the rubber carbon black is the most important ingredient for long wear zinc oxide is another ingredient used to add strength sulfur is used to cure or vulcanize the rubber other chemicals are used to speed the curing or vulcanizing process however the basic ingredients of the pneumatic tire are those you've just seen every tubeless tire consists of four basic parts the tread applies the inner liner and the bees each of these parts uses a specially formulated rubber compound the compounding process starts with this rubber cutting machine heated knives cut the veils of rubber into workable sized chunks these chunks of raw rubber next go into a room-sized oven where the rubber is softened by heat to make it more pliable when the correct temperature has been reached the rubber chunks are fed into a machine called a plastic ater which heats and grinds them up the rubber as it comes from the plastic ater is ready for mixing with the other ingredients the quality of the finished product depends on the proper mix before mixing a batch of rubber each ingredient is weighed according to exact formula the rubber and other ingredients are dumped into the mixing machine called a Banbury which is on the floor below this giant mixer ensures all ingredients being thoroughly blended together the Banbury operates on a time controlled schedule at the end of the time cycle the mixture leaves the Banbury and falls between the rollers of a machine known as a mill where sulphur in sheet form is added and worked into the compound the finished compound rolls out of the mill in a continuous black sheet after passing through a soapstone bad to reduce stickiness the sheet is automatically cut into lanes and draped on a moving conveyor our raw rubber stock has now been converted into a specific compound to be used in making one of the basic parts of the tire let's take the bead first each tire has two bees which fit onto the rim of the wheel help make an airtight seal and in combination with air pressure hold the tire firmly on the rim remember the bead has a tough inner core made of separate strands of high-tensile steel wire these separate strands of wire feed into a machine where they are encased in rubber and a narrow ribbon of rubber covered wires comes out the rubber covered wire ribbon feeds into the bead former wear a revolving wheel winds the ribbon upon itself a number of times to build up a hoop of the required thickness and strength the bead cover a rubberized fabric used to hold the wire together is apply then a rubber coated fabric called the flipper strip is added this is a completed bead circle the flipper strip is important because it locks the bead in place inside the tire probably the greatest single advance entire safety since the invention of the pneumatic tire is the tough airtight butyl inner liner which replaces the tube in a tubeless tire a double layer of this special rubber is permanently bonded to the tire carcass from bead to be if a few chords are broken by a severe impact the flexing action enlarges the break eventually a small hole may appear in the inner liner through which the air escapes slowly the same holds true with a simple puncture such as a nail or a piece of glass there is no sudden flat as there would be with the to another basic part of the tire is the ply there are four plies which form the chord body or the carcass of most passenger car tires these cord plies give the tire the strength to absorb impacts and shocks and to carry the load the manufacture of ply stock starts in the Creole room this is a perfectly planned arrangement by which thousands of schools feed cords to a collection point where each cord becomes part of a continuous web the cord web then passes down to the floor below where it goes through a latex rubber dip to increase its adhesiveness it then travels through a series of drying rollers which heat set and temper the cords as the web enters the calendar to be coated with rubber the cords are carefully checked for a line here under great pressure the cord web is sandwiched between two sheets of rubber forming the fly stock the gauge or thickness of the ply material is automatically controlled to very close tolerance electronically by a beta ray gauge the finished ply stock is wound into big rolls in which the cords are running lengthwise the rolls then go to a machine called a bias Qatar where the ply stock is cut to proper size at an angle the bias cut pieces are joined together again to make a continuous strip of buy stock ready for the tire builders the cords are now running diagonally across the ply stock instead of lengthwise this is a piece of bias cut ply stock by bias cutting ply material in which the courts run diagonally in one direction and bias cutting ply material in which the cords run diagonally in the other direction when the plies are assembled layer by layer the cords will cross each other at an angle this crisscrossing of the cord gives the tire maximum strength safety comfort stability and durability here is a section of tread stock the tread is the business end of the tire the part which couples the vehicle to the road long mileage traction and skid resistance depend largely on the design and composition of the tread note the thickness in the center part and the tapering sides the center thickness will receive the tread design and the tapered wings will form the shoulders and sidewall covers of the tire now we'll see how it's made this is tread rubber being worked through a warm-up mill to make it pliable the strip feeding off overhead goes to an extruder a machine that forces the rubber would die to form the tread stock to a precise size and weight as the form the tread stock leaves the extruder it's a continuous strip the strip is water too to prevent shrinkage and premature curing then it's bevel cut to length specification as the tread slab continues along the conveyor it is automatically weed the finished sections of tread stock are loaded on trays to be taken to the tire production line we have covered the tread applies the inner liner and the beads now let's go to the production line and see how a tire is built here is a tire building machine although this machine does many things automatically the skilled craftsmanship of the tire builder is an important factor in the quality of the finished tire the tire builder has slipped feed circles into position and locked the drum in shape first he wraps two layers of air tight doodle rubber around the drum this is the inner liner of the tubeless tire next the first layer of climate Irial is wrapped on over the inner liner the second layer of Pi material is wrapped over the first layer as the drum spins stitching wheels beneath the drum roll applies down tight and permanently bond them to the inner liner now the beast or the edges of the flies are turned up over the beam the third layer of ply material is applied followed by the fourth and last play the finishing strips are applied for extra strength in the vital bead area of the tire next the prayer is rolled on the drum over the fourth layer of ply material the tire builder makes sure the bevel cut ends meet properly pitching wheels beneath the drum find the tread and plies together and the finishing strips are rolled around the beam the drum collapses automatically and the keg shaped green tire is removed from the machine and placed on a stand for the treads place you've pressed tight at this point it doesn't look much like a tire doesn't now before we see the molding and curing process which will change this egg shaped green tire into its finished form let's go to a tire building assembly line where many of the tire building operations are performed automatically this is where large quantities of the same size and type of tires are produced with speed and efficiency at the beginning of the assembly line the butyl liner goes on automatically just the right number of turns and the drum advances to the next station here workers are applying the first and second cord fly the third and fourth flies are applied in the same manner further down the line the flipper strips which tie the beads into the fire are turned off automatically at this station near the end of the line a worker applies the white sidewall and finally the green pyres come off the line and move to the forming and curing molds the molding ensuring is done in the machine called a bag o matic press each press molds two tires at a time in each mold the green tires are formed and cured automatically curing is just another name for vulcanizing which takes place under pressure and at high temperature as the mold closes you can see the keg shape starting to change to the familiar donut form of a finished tire while attire cures the tread design size brand name and other markings are formed by the steel dies in the mold shirring time is automatically controlled by precision instruments at the end of the period the mold automatically opens and the cured tire is now ready for the finishing operation the tire is hand trim to remove excess rubber which flowed into air vents in the mold black area of each tire is painted to dress up the appearance all tires are carefully inspected for workmanship and appearance all tires are checked for balance for white walls the next step is a buffing operation that puts a smooth even line of separation where the white walls strip joins the black then the white wall is polished and sprayed with a protective coating to keep it clean the finished tires are shipped to warehousing and distribution centers all over the country for quick delivery to retailers tires are something most people take for granted but tires such as you've seen late in this film have a real job to do they float the weight of a vehicle on a cushion of air they provide traction for starting and stopping their resists kidding they soak up the hammering pounding blows of the wheels on the road they traveled in all kinds of weather with only a minimum of care they stay on the job for thousands and thousands of miles the pneumatic tire has been with us now for more than 65 years each year has performed a little bit better than the year before through the years BF Goodrich has pioneered such notable developments as the first chord tire and the first tubeless tire now standard in the industry because of continuous research development and constant improvement of manufacturing facilities today's bfgoodrich tires are more dependable they are safer and deliver more mileage than ever before you