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--Captions by VITAC-- www.vitac.com
CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS
Narrator: TODAY, ON "HOW IT'S MADE"...
THINNER THAN A HUMAN HAIR,
ULTRATHIN GLASS FLEXES LIKE PLASTIC.
IT CAN ALSO HAVE GREATER ELECTRICAL SENSITIVITY,
MAKING IT USEFUL FOR THINGS
LIKE FINGERPRINT SCANNING ON SMARTPHONES.
MANUFACTURERS HAVE ONLY JUST BEGUN
TO EXPLORE THE POTENTIAL OF THIS NEW CLASS OF GLASS.
WHEN IT COMES TO SHEER FLEXIBILITY,
THIN IS IN.
ULTRATHIN GLASS BENDS LIKE A SHEET OF PAPER
AND A CHEMICAL PROCESS ENSURES THAT IT'S EXTREMELY ROBUST.
TO MAKE ULTRATHIN GLASS,
MANUFACTURERS USE STANDARD MATERIALS,
SUCH AS LIME, SAND, SODA, AND POTASH.
THEY STORE THE INGREDIENTS IN SEPARATE SILOS,
UNTIL IT'S TIME FOR PRODUCTION.
THEN, INSIDE THE FACTORY, A LONG CABLE
DELIVERS ELECTRICITY TO POWER A WEIGH CART.
AS THE DRY INGREDIENTS FLOW OUT OF THE SILOS AND DOWN CHUTES,
THE CART MOVES FORWARD TO COLLECT THEM.
IT WEIGHS THE INGREDIENTS
UNTIL IT HAS THE CORRECT AMOUNTS FOR THE GLASS RECIPE
AND THEN CLOSES THE LID AUTOMATICALLY.
A WORKER MEASURES THE SECONDARY, SMALLER, INGREDIENTS MANUALLY
AND ADDS THEM TO THE BATCH.
THESE INGREDIENTS ENHANCE QUALITIES
LIKE OPTICAL CLARITY OR ELECTRICAL SENSITIVITY.
THE CART TRANSFERS THE BATCH TO A MIXER.
AS IT BLENDS EVERYTHING TOGETHER,
THEY ADD BITS OF BROKEN, OR WASTE, GLASS TO IT
FOR RECYCLING PURPOSES.
ONCE IT'S BEEN THOROUGHLY MIXED, A LIFT RAISES
A FUNNEL-SHAPED CONTAINER UP TO THE BASE OF THE MIXER
AND THE MIXER RELEASES THE BATCH INTO IT.
A WORKER HAULS THE BATCH-LADEN FUNNEL TANK TO THE NEXT STATION.
THERE, A CRANE TAKES OVER AND LOWERS THE TANK
ONTO A FEEDER SYSTEM JUST ABOVE A GAS-AND-ELECTRIC FURNACE.
A TRAPDOOR OPENS AT THE FUNNEL'S BASE
AND THE MIXTURE FLOWS INTO THE FEEDER MECHANISM.
IT'S A KIND OF SHOVEL THAT SLOWLY PUSHES THE MIXTURE
INTO THE FURNACE,
WHICH HAS BEEN FIRED TO A BLAZING 2,732° FAHRENHEIT.
THE SHOVEL CONTINUOUSLY ADDS MORE INGREDIENTS
TO KEEP PRODUCTION FLOWING.
GLASS PRODUCTION RUNS 24/7.
THE MELTING GLASS REACHES THE CONSISTENCY OF HONEY.
THE MOLTEN GLASS FLOWS OUT THROUGH A NARROW SLIT
AND THIS SLIT ESTABLISHES
THE ULTRATHIN DIMENSIONS OF THE GLASS.
COOLING THE GLASS SLOWLY
RELIEVES INTERNAL STRESSES AS THE GLASS SOLIDIFIES.
ULTRATHIN GLASS CAN BE JUST 25 MICRONS THICK.
THAT'S FINER THAN A HAIR.
AND IT'S THIS THINNESS THAT MAKES IT SO FLEXIBLE.
THE GLASS BENDS TO LOOP DOWN AND UP ACROSS ROLLERS
AS IT JOURNEYS FORWARD
IN A CONTINUOUS, NEARLY 2-FOOT-WIDE SHEET
AND, UNLIKE ORDINARY GLASS, IT DOESN'T CRACK.
IT THEN TRAVELS PAST TINY CAMERAS AND LASER SENSORS
THAT LOOK FOR DEFECTS, LIKE BUBBLES.
A COMPUTER MAPS ANY FLAWS, SO THEY CAN BE AVOIDED
WHEN THE GLASS IS CUT INTO SMALLER PIECES.
A REVOLVING SPOOL ROLLS UP THE GLASS,
ALONG WITH A PLASTIC LINER,
WHICH KEEPS THE GLASS LAYERS FROM STICKING TO ONE ANOTHER.
ONCE 546 YARDS OF THIN GLASS HAS BEEN WOUND ONTO THE SPOOL,
AN AUTOMATED SYSTEM CUTS THE GLASS
AND SLIDES THE SPOOL PARTWAY OFF THE CORE AND ONTO A RACK.
THE OPERATOR GIVES IT A PUSH TO COMPLETE THE TRANSFER
AND THEN ROLLS THE RACK TO THE NEXT STATION.
A LAB TECHNICIAN SLICES OFF A FRAGMENT OF THE GLASS
AND INSERTS IT IN A MICROMETER.
IT GAUGES THE THICKNESS OF THE SPECIMEN
AND CONFIRMS THAT IT'S SUPERTHIN.
ANOTHER LAB WORKER PLACES A BIGGER SEGMENT OF THE GLASS
UNDER A CUTTER.
HE ALIGNS IT CORRECTLY AND THEN ACTIVATES THE CUTTER.
IT SCRIBES THE GLASS, SO IT CAN BE BROKEN ON THIS LINE,
CREATING SMALL SCREENS FOR SMARTPHONES AND SMARTWATCHES.
A LAB TECHNICIAN EXAMINES THE GLASS FOR SCRATCHES
UNDER A BRIGHT LIGHT AND CONFIRMS THAT IT'S UNDAMAGED.
WITH THAT OUT OF THE WAY, IT'S TIME TO HAVE A LITTLE FUN
WITH A STRIP OF THIS ULTRATHIN GLASS.
A WORKER BENDS IT INTO A CIRCLE AND TIES IT.
IT'S HARD TO BELIEVE THIS IS GLASS.
LATER, A CHEMICAL TREATMENT
WILL FURTHER STRENGTHEN THE ULTRATHIN GLASS,
SO THAT THE CHANCE OF CRACKS OR BREAKS WILL BE VERY THIN.
WHEN WOODEN SHIPPING PALLETS BREAK AND NEED REPAIR,
OR OUTLIVE THEIR USEFULNESS, THEY CAN BE TAKEN APART
BY PALLET-DISMANTLING MACHINES, WHICH SAW THROUGH THE NAILS
TO SEPARATE THE WOOD BLOCKS AND PLANKS.
SALVAGEABLE PIECES BECOME NEW PALLETS,
WHILE BROKEN PIECES GO INTO A WOOD CHIPPER.
WITH ITS POWERFUL BAND SAW, THIS PALLET-DISMANTLING MACHINE
SLICES THROUGH THE NAILS THAT FASTEN
THE PALLET'S WOOD BLOCKS TO ITS TRANSVERSAL PLANKS.
THE MACHINE'S SHELL, THE EQUIVALENT
OF THE BODY PANELS ON A CAR, IS MADE OF STEEL SHEETS.
A COMPUTER-GUIDED LASER CUTTER CUTS THEM TO THE REQUIRED SHAPE.
THEN, WORKERS BEND THE ENDS ON A BRAKE PRESS
TO MAKE EDGES WITH PERFECTLY FORMED CORNERS.
ONCE SHAPED, THE SHELL PARTS GO TO A PAINT SHOP.
WORKERS BUILD THE STRUCTURE OF THE MACHINE
OUT OF HEAVY-DUTY STEEL TUBES.
AFTER SAWING THEM TO THE LENGTH REQUIRED,
THEY SMOOTH THE ROUGH-CUT EDGE WITH A HAND-GRINDER.
WORKERS MARK WHERE THEY HAVE TO MAKE OPENINGS
FOR VARIOUS PARTS AND DRILL THE HOLES.
THEY WELD THE TUBES TOGETHER TO ASSEMBLE THE STRUCTURE.
THEY CLEAN THE SURFACE WITH ACID TO REMOVE TRACES OF LUBRICANT.
THEN, THEY SPRAY PAINT THE STRUCTURE.
THE WORKERS ASSEMBLE THE MECHANICAL PARTS
TO THE STRUCTURE.
THEY BOLT ON A PLATE TO SUPPORT THE MACHINE'S ELECTRIC ENGINE.
THEN, ON EACH SIDE, THEY INSTALL A WHEEL.
NEXT, WORKERS INSTALL THE MOTOR REDUCER.
TO THAT, THEY BOLT THE MACHINE'S 2,800-RPM ENGINE.
THE MOTOR REDUCER DECREASES THE SPEED OF THE ENGINE
TO THE SAWING SPEED REQUIRED TO DISMANTLE THE PALLET.
JUST ABOVE THE TIRES ON BOTH SIDES,
THEY BOLT A BLADE GUIDE TO THE STRUCTURE.
THEY INSTALL THE FRONT OF THE MACHINE'S SHELL
AND LOWER THE MACHINE'S HEAVY, STEEL WORKTABLE.
NOW, THE BAND-SAW BLADE, WHICH HAS A SAFETY COVER
OVER ITS SHARP TEETH UNTIL THE MACHINE IS OPERATIONAL.
ON EACH SIDE OF THE WORKTABLE,
WORKERS ALIGN THE BLADE WITH A TIRE
AND INSERT IT BETWEEN THE WHEELS OF THE BLADE GUIDE.
THE BLADE IS STEEL, WITH CARBIDE TIPS
FOR ADDED STRENGTH AND RESISTANCE TO WEAR.
THEY TURN THIS BOLT TO ADJUST THE TENSION.
THEY ENCLOSE THE TIRE AND BLADE GUIDES
IN THE SIDE SECTIONS OF THE MACHINE'S SHELL.
THEN, WORKERS INSTALL TWO PNEUMATIC CYLINDERS
FOR RAISING AND LOWERING A SAFETY CAGE
THAT GOES OVER THE WORKTABLE TO PROTECT THE MACHINE OPERATOR.
NEXT, ANOTHER PNEUMATIC CYLINDER,
THIS ONE, AT THE REAR FOR THE MACHINE'S GUIDE ARM.
THE GUIDE ARM, INSTALLED NEXT, HELPS MOVE THE PALLET AROUND
WHILE THE MACHINE'S BAND-SAW BLADE CUTS IT APART.
THEY INSTALL THE SAFETY CAGE OVER THE WORKTABLE,
THEN HOOK UP THE CABLES THAT FEED COMPRESSED AIR
TO THE PNEUMATIC CYLINDERS.
THEY INSTALL ANOTHER SAFETY CAGE OVER THE BACK OF THE MACHINE,
THEN, A PRESSURE REGULATOR FOR PNEUMATIC CYLINDERS.
THEY MOUNT THE MACHINE'S CONTROL PANEL ON THE SHELL.
IT'S WIRED TO THE ENGINE AND PNEUMATIC SYSTEM,
AS WELL AS A SET OF FOOT PEDALS THAT MOVES THE TABLE UP AND DOWN
AND ANOTHER PEDAL THAT MOVES THE GUIDE ARM.
THE OPERATOR PLACES THE PALLET ON THE WORKTABLE
AND LOWERS THE SAFETY CAGE.
WITH THE FOOT PEDAL, HE MOVES THE ARM TO THE RIGHT
TO ANGLE THE PALLET AGAINST THE BLADE.
THIS LETS IT SLICE THROUGH MULTIPLE NAILS
HOLDING THE WOOD PLANKS AND BLOCKS TOGETHER.
OFTEN FROSTED AND ADORNED WITH SPRINKLES,
A CUPCAKE IS A SUGARY INDULGENCE THAT YOU DON'T HAVE TO SHARE.
WE DON'T REALLY KNOW WHO INVENTED THEM,
BUT CUPCAKES HAVE BEEN AROUND FOR A CENTURY OR MORE,
MUCH TO THE SATISFACTION OF THOSE
WHO WANT A LITTLE CAKE ALL TO THEMSELVES.
THESE MINICUPCAKES ARE THE SWEETEST LITTLE THINGS
AND THERE'S PLENTY FOR EVERYONE
BECAUSE THEY'RE MASS-PRODUCED IN A FACTORY.
THE DAIRY AND NUT-FREE RECIPE STARTS WITH CANOLA OIL.
A WORKER POURS A MEASURED AMOUNT INTO A HUGER MIXER BOWL.
A BLEND OF BAKING POWER, SEA SALT,
AND OTHER MICROINGREDIENTS IS NEXT.
HE THEN ADDS A BIG BAG OF SUGAR.
THEY'LL BE MAKING 15,000 MINICUPCAKES IN THIS BATCH.
PASTRY FLOUR FLOWS INTO THE MIXER FROM A SILO NEARBY.
HE ADDS COCOA, FOR CHOCOLATE FLAVORING,
THEN, ACTIVATES THE MIXER, TO BLEND IT ALL TOGETHER.
NEXT ARE THE EGGS.
THEY'LL ACT AS A BINDING AGENT FOR THE CHOCOLATE BATTER
AND WILL HAVE A LEAVENING EFFECT DURING BAKING.
A QUICK MIX FOLDS THE EGGS INTO THE CHOCOLATEY BLEND.
A PUMP NOW TRANSFERS THE BATTER TO THE NEXT STATION.
THE BAKERY'S TEMPERATURE IS CRITICAL DURING PUMPING.
TOO WARM, AND THE MIXTURE WILL BE TOO THIN TO PUMP.
TOO COOL, AND IT WILL BE TOO THICK.
THE PUMP DELIVERS THE BATTER TO A HOPPER.
DOWN THE LINE A BIT, A CONVEYOR MOVES BAKING TRAYS FORWARD.
A MACHINE USES SUCTIONING DEVICES
TO PICK UP PAPER LINERS, FLIP THEM RIGHT-SIDE-UP,
AND INSERT THEM IN THE BAKING TRAYS.
VALVES OPEN AND DISPENSE THE BATTER IN THE HOPPER
INTO THE CUPCAKE LINERS IN THE PANS.
THE SYSTEM CONTROLS THE FLOW OF BATTER,
SO IT ONLY FILLS THE LINERS ONE-THIRD OF THE WAY.
THIS LEAVES ROOM FOR THE CAKE TO RISE DURING BAKING.
THE PANS MOVE THROUGH DIFFERENT LEVELS,
WITH A RANGE OF TEMPERATURE ZONES
OVER A PERIOD OF 25 MINUTES,
FINALLY EMERGING FROM THE OTHER SIDE.
DURING BAKING, THE CUPCAKES HAVE RISEN ABOVE THE LINERS.
THEY NOW HEAD INTO A COOLING CHAMBER.
THEY STAY IN HERE FOR 20 MINUTES,
WHILE FANS BLOW AIR ONTO THEM TO COOL THEM DOWN.
THE COOLING FIRMS UP THE CAKES.
A ROBOT PLUNGES PINLIKE TENTACLES INTO THE CUPCAKES
TO LIFT THEM OUT OF THE PANS WITH THE PAPER LINERS ATTACHED.
IT TRANSFERS THEM TO THE PACKAGING CONVEYOR LINE.
WORKERS PACK THEM IN CLAMSHELL PLASTIC CONTAINERS,
A DOZEN TO EACH ONE.
THEY LEAVE THE CONTAINERS OPEN
BECAUSE THEY STILL NEED TO DECORATE THESE CUPCAKES.
AHEAD, FLUFFY CHOCOLATE ICING FLOWS
OUT OF A HOPPER INTO APPLICATORS.
THEY DEPOSIT THE ICING IN A SWIRL ONTO THE CUPCAKES,
ADDING NEARLY AN INCH OF HEIGHT AND A LOT MORE SWEETNESS.
DOWN THE LINE, WORKERS LOAD SUGARY SPRINKLES
INTO ANOTHER HOPPER.
A FEEDER DISPENSES A FEW MORE OF THE SPRINKLES
ONTO EACH OF THE FROSTED CUPCAKES.
THE CONTAINERS THEN RIDE BY A RAIL THAT FOLDS THE LIDS OVER.
A PUSHER DEVICE PRESSES DOWN ON THE LIDS TO CLOSE THEM TIGHTLY.
THE CONTAINERS OF MINICUPCAKES THEN MEET UP WITH A ROLLER
THAT APPLIES THE ADHESIVE-BACKED LABELING.
BEFORE THE CUPCAKES CAN LEAVE THE FACTORY,
A TECHNICIAN TESTS A SAMPLE FROM THE PRODUCTION LINE.
HE CRUMBLES SOME OF THE CAKE INTO PODS
AND PLACES THEM IN A MACHINE.
THE MACHINE PROBES THE WATER CONTENT AT A MICROSCOPIC LEVEL
TO DETERMINE IF THE CUPCAKE IS MOIST ENOUGH.
ANOTHER TEST EVALUATES THE CUPCAKE'S TEXTURE.
WHEN THE SAMPLES PASS THIS TECHNOLOGICAL SCRUTINY,
THE CUPCAKES ARE READY FOR HUMAN TASTE BUDS.
AS A COMPONENT OF MECHANICAL EQUIPMENT,
SEAMLESS TUBE IS STRONGER, AND THEREFORE MORE RESISTANT
TO PRESSURE AND TENSION, THAN TUBE WITH A WELDED SEAM.
THAT'S BECAUSE SEAMLESS TUBE IS MANUFACTURED
FROM A SOLID BAR OF STAINLESS STEEL,
RATHER THAN FROM A STRIP OF STAINLESS
THAT'S ROLLED AND WELDED INTO A TUBE.
SEAMLESS STAINLESS-STEEL TUBE
IS USED WHEN RELIABILITY IS CRITICAL;
FOR EXAMPLE, IN AEROSPACE ENGINES,
NUCLEAR EQUIPMENT, AND MEDICAL DEVICES.
THE MANUFACTURER PURCHASES STAINLESS-STEEL TUBES
IN A RANGE OF LENGTHS, DIAMETERS, AND THICKNESSES.
WORKERS SELECT THE RIGHT STARTING SIZE
FOR THE SPECIFIC TUBE THE CUSTOMER HAS ORDERED.
THEY CHECK THE LENGTH WITH A MEASURING TAPE,
THEN USE A LARGE MICROMETER TO MEASURE THE OUTSIDE DIAMETER.
THEY SWITCH TO A SMALLER MICROMETER
TO MEASURE THE WALL THICKNESS.
THEN, THEY WEIGH THE TUBES.
IF THE RAW MATERIAL MEETS ALL THE SPECS,
PRODUCTION CAN BEGIN.
THEY INSERT ONE END OF EACH TUBE INTO THIS ROTARY SWAGER.
IT SHAPES THE END TO A POINT,
TO ENABLE IT TO FIT THROUGH A DIE WITH A SMALLER DIAMETER.
WORKERS SPREAD LUBRICANT INTO A STEEL BAR,
INSERT IT INTO THE OTHER END OF THE TUBE,
THEN INSERT THE POINTED END THROUGH A DRAW DIE.
THIS CARRIAGE THEN GRABS THE PROTRUDING POINT
AND DRAWS THE FULL LENGTH OF THE TUBE
THROUGH THE DIE AND OVER THE STEEL BAR.
THE DIE REDUCES THE TUBE TO A SMALLER OUTSIDE DIAMETER,
WHILE THE BAR SETS THE DESIRED INSIDE DIAMETER.
THE TUBE WALLS THIN OUT AND THE TUBE ELONGATES IN THE PROCESS.
THE NEXT MACHINE'S TWO ROLLERS
APPLY PRESSURE TO THE OUTSIDE OF THE TUBE AS IT PASSES.
THIS EXPANDS THE TUBE SLIGHTLY, CREATING A SLIGHT GAP
BETWEEN THE TUBE WALLS AND THE BAR INSIDE.
THIS ENABLES THE NEXT MACHINE TO EXTRACT THE BAR.
FINALLY, WORKERS SAW THE POINT OFF THE TUBE.
THEY PLACE SEVERAL TUBES AT A TIME IN A DEGREASING UNIT,
WHICH USES A CLEANING SOLUTION TO REMOVE ALL TRACES
OF LUBRICANT THE TUBES PICKED UP DURING THE DRAW PROCESS.
WORKERS THEN TRANSFER THE TUBES TO DRYING TANKS,
POSITIONING THEM AT A SLIGHT DOWNWARD ANGLE.
AS AIR BLOWS THROUGH THE TUBES FOR ABOUT A HALF HOUR,
ALL OF THE CLEANING SOLUTION EITHER DRAINS OR EVAPORATES.
TO FURTHER CLEAN THE INSIDE OF THE TUBES,
WORKERS INSERT A FELT WAD INTO EACH ONE,
THEN SQUIRT IN SOME CLEANING SOLVENT.
THEY SHOOT IN COMPRESSED AIR TO FORCE THE WAD DOWN THE TUBE.
AS THE WAD TRAVELS THE LENGTH OF THE TUBE,
IT WIPES THE INSIDE WALL WITH THE CLEANING SOLVENT.
NEXT, WORKERS STRAP THE TUBES TO A BELT
THAT TAKES THEM ON A 30-MINUTE TRIP THROUGH A FURNACE.
THE TEMPERATURE INSIDE IS MORE THAN 1,800° FAHRENHEIT.
THIS INTENSE HEAT SOFTENS THE STEEL,
WHICH HAD HARDENED AS A RESULT
OF HAVING BEEN PULLED THROUGH THE DRAW DIE EARLIER.
THIS PROCESS IS CALLED ANNEALING AND IT SLIGHTLY WARPS THE TUBES,
SO, NEXT, THEY PASS THROUGH A STRAIGHTENING MACHINE.
THEN, THE ENTIRE CYCLE REPEATS,
UNTIL IT'S REDUCED TO PRECISELY THE DIAMETER
AND WALL THICKNESS THE CUSTOMER ORDERED.
THE FINISHED TUBE CAN BE
UP TO 40 TIMES ITS ORIGINAL STARTING LENGTH.
TO ENSURE THE STRUCTURAL INTEGRITY OF EACH TUBE,
WORKERS RUN AN ELECTRICAL CURRENT
AROUND THE CIRCUMFERENCE.
A BREAK IN THE CURRENT INDICATES A DEFECT,
WHICH WORKERS THEN CUT OUT WITH A SAW
BEFORE CUTTING THE TUBE INTO THE SPECIFIC LENGTHS
THE CUSTOMER ORDERED.
THE SAW CUTS LEAVE BURNS, ROUGH EDGES,
SO WORKERS INSERT THE CUT ENDS IN A DEBURRING MACHINE
WHICH GRINDS THE EDGES SMOOTH.
THE LAST STEP IS TO SUBMERGE THE TUBES IN AN ACID SOLUTION,
TO REMOVE ANY IRON PARTICLES PICKED UP FROM THE PROCESSING.
THIS PREVENTS THE TUBES FROM RUSTING.
IN ADDITION TO INSPECTING EVERY TUBE THAT LEAVES THE FACTORY,
QUALITY-CONTROL TESTING OF RANDOM SAMPLES
ENSURES THE PRODUCT MEETS ALL TECHNICAL SPECIFICATIONS.
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