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--captions by vitac--
Www.Vitac.Com
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Captions paid for by
Discovery communications, inc.
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Narrator:
Today on "How it's made"...
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...Car engines...
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...Flour...
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...Recliners...
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...And envelopes.
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Car engines work
By internal combustion,
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A process that happens in each
Of the engine's cylinders.
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00:00:58,896 --> 00:01:01,896
Air and a drop of gasoline
Enter the cylinder.
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The piston moves upward,
Compressing the mixture.
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00:01:05,000 --> 00:01:07,068
The spark plug
Ignites the gasoline
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Causing an explosion
That drives the piston downward,
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Powering the engine.
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Engine components are housed in
What's called the engine block.
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It arrives at this plant
Partially made.
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Here, they finish it off by
Machining the cylinder bores,
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The holes in which
The pistons move up and down.
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The tool
Carves a crisscross pattern
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On the cylinder bore walls.
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Lubricating oil will cling
To the grooves in this pattern
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Enabling the pistons
To move smoothly.
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After machining,
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The engine block
Travels upside down
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To the engine assembly line.
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When it arrives there,
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A scanner records
The block's traceability code,
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A barcode
That enables the factory
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To track the block through
Every stage of production.
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As the engine block
Travels down the line,
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00:02:01,586 --> 00:02:03,103
Error-proofing devices
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Ensure that each component
Is installed properly.
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Elsewhere in the factory,
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The crankshaft
Is slowly taking shape.
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The crankshaft is a bar
That's rotated
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By the up-and-down motion
Of the pistons.
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As it turns, it transfers power
To the transmission.
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The crankshaft starts out as
A roughly shaped steel forging.
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Robotic arms
Pass it down the line
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From station to station until,
20 tooling machines later,
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It's fully formed.
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Now they install
A steel disc with teeth
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Called the reluctor ring.
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They heat it and press it
Onto the crankshaft.
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00:03:04,655 --> 00:03:07,965
As it cools,
It shrinks to a tight fit.
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00:03:07,965 --> 00:03:10,655
This ring helps time
The combustion cycle.
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As it spins,
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Its teeth
Pass in front of a sensor,
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Which reads
The crankshaft's position
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00:03:16,620 --> 00:03:19,413
And tells the engine
To fire the spark plugs
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At precisely the right moment.
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00:03:23,965 --> 00:03:26,793
Now they balance
The crankshaft.
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If it's off-kilter,
The engine will vibrate.
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A computer analyzes the spin
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And determines whether
They need to drill out metal
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At certain points
To achieve equilibrium.
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Back on the engine
Assembly line,
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The engine blocks
Are still upside down.
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A robot lubricates
The four bearings
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On which the crankshaft
Will turn,
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Then it drops the crankshaft
Into position.
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The pistons come next --
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00:04:00,275 --> 00:04:04,655
Six per engine because these
Are six-cylinder engines.
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The pistons are made
Of aluminum.
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Robots install them
Into the cylinder bores
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Of the engine block.
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A steel connecting rod attaches
Each piston to the crankshaft.
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00:04:21,103 --> 00:04:24,275
Now workers can close up
The back of the engine block.
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00:04:24,275 --> 00:04:27,068
A robot applies sealant
To the rear cover.
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They bolt it on manually
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With a tool called
A multi-spindle torque gun.
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On another line,
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They assemble the two heads
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That'll cover the top
Of the engine block.
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This robot is applying sealant
To spark plug tubes
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Before inserting them
Into the heads.
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The heads cap off
The cylinder bores.
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They provide each cylinder with
A spark plug and four valves --
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Two for allowing
The fuel mixture in
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And two for releasing
The exhaust.
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The black tubes running front
To back are the cam shafts,
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The components that open
And close those valves.
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There are four per engine.
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A robot applies sealant
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00:05:18,689 --> 00:05:21,482
And then bolts a cover onto
The front of the engine block,
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The head, and a component
Called the timing chain.
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00:05:24,896 --> 00:05:28,000
This chain connects the
Crankshaft to the cam shafts
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So that they rotate in unison.
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This ensures the valves open
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When the pistons
Are in the right position.
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Finally, they spin the engine
Mechanically
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To make sure the components
Function properly.
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Narrator:
The grain most commonly
Ground into flour is wheat.
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Flour mills use high-protein
Or hard-wheat species
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To make bread flour
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And lower-protein
Or soft-wheat species
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To produce cake
And pastry flour.
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All-purpose flour is a
Compromise with medium protein.
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As soon as the wheat shipment
Arrives,
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A grain probe vacuums up samples
From throughout the load.
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If the samples
Pass quality inspection,
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The mill gives the truck
The go-ahead
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To dump the wheat
Onto an underground conveyor.
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From there, the grain
Goes into a cleaning machine,
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Where a system of sieves
Removes impurities
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Such as straw,
Sticks, and grain dust.
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The wheat then goes into storage
Silos until milling time.
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The protein content of wheat
Varies by species,
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So the first step
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Is to blend together
The right varieties of wheat
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For the type of flour
They'll be making.
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From the blender,
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The wheat goes through a second,
More intensive cleaning system
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That removes the tiniest
Of impurities,
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Such as weed seeds and dust.
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On the way
To the milling machines,
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A scale
Tracks production quantities.
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This mill's vertical-production
Line is five stories high.
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Gravity
Carries the wheat downward
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Through a succession
Of milling machines.
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Each one grinds the grain
Between steel rollers
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And then sifts it.
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Particles too large
To pass through a sieve
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00:07:29,896 --> 00:07:33,551
Continue downward into the next
Milling machine and so on.
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By the time the wheat
Hits the last machine,
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Anything
That's not fully processed
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Gets vacuumed up to the top
To begin the cycle again.
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Mills make white flour
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By grinding only the
Wheat kernel's soft inner part,
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Called the endosperm.
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This requires removing the bran,
The kernel's hard skin,
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And the germ, its seed.
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That separation begins
As soon as the wheat kernels
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Enter the very first
Milling machine.
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Rollers break off
The germ and bran
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And crush the endosperm
Into pieces called semolina.
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Sifting removes the germ
And loose bran pieces,
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But much of the semolina remains
Covered in bran particles.
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So between each milling station
Is a purifier,
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A machine that uses
Controlled air currents
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To float the lighter bran
Above the heavier semolina,
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Enabling sieves to separate
The two components.
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The semolina goes through
Repeated grind, sift,
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00:08:32,172 --> 00:08:36,310
And purify cycles
Until it's completely clean.
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Only then can it be
Finely ground into flour.
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The ground semolina passes
Through a series of sieves.
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This ensures it doesn't leave
The final milling machine
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Until it's been ground
To the right powdery texture.
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There are three main types
Of white-wheat flour.
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Bread flour has high protein,
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Enabling dough to rise well
And bake to a firm texture.
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Cake flour has low protein,
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Which produces
A crumbly texture.
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All-purpose flour
Is the compromise --
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00:09:10,517 --> 00:09:12,344
Its medium-protein content
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Makes it suitable for baking
Both bread and cakes.
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By the end of production,
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The flour mill has produced
Three distinct products --
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Bran, used for animal feed
And baking...
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00:09:26,724 --> 00:09:28,827
...White-wheat flour...
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And wheat germ
For the health-food market.
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Leftover by-products
Go into livestock feed.
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In the mill's
Quality-control lab,
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They bake the product
For which the flour is designed
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And then examine its appearance,
Texture, and taste.
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They use specialized equipment
To calculate the volume,
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The density, protein,
And moisture contents.
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00:09:58,758 --> 00:10:02,517
With baked goods destined for
Retail sale, like these cookies,
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It's especially important
To measure the dimensions.
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If dough overexpands,
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The cookies
Won't fit in their package.
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Just prior to packaging,
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The mill enriches
Its white flour
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With vitamins and minerals.
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This replaces the vitamins
And minerals lost
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When the milling process
Removed the bran and germ.
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They shake the bags
To settle the flour.
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00:10:25,896 --> 00:10:30,275
Bagged flour in various sizes
Goes out to supermarkets,
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00:10:30,275 --> 00:10:32,517
Restaurants,
And commercial bakeries,
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While tanker trunks
Ship bulk flour
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To large industrial bakeries.
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Narrator:
The first reclining armchair
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Was introduced by
The la-z-boy company in 1928.
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00:10:52,931 --> 00:10:56,034
Today, many companies
Make motion furniture,
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00:10:56,034 --> 00:10:57,724
As the industry calls it,
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00:10:57,724 --> 00:11:01,586
And the term "Recliner" no
Longer refers to just armchairs.
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00:11:01,586 --> 00:11:06,448
You can buy reclining couches
And even reclining sectionals.
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This factory makes
Reclining chairs and couches
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In both fabric and leather.
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00:11:15,586 --> 00:11:17,931
The furniture construction
Is the same,
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Regardless of the material,
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But leather upholstery
Requires a few extra steps.
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They begin
By inspecting the hide,
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00:11:26,206 --> 00:11:29,379
Marking serious defects
With one color of tape
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00:11:29,379 --> 00:11:32,655
And minor imperfections
With another.
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00:11:32,655 --> 00:11:34,793
A computer-programmed
Cutting machine
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Scans and registers
The tape markings,
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00:11:37,344 --> 00:11:41,137
Then automatically cuts and
Discards the defective parts.
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00:11:41,137 --> 00:11:43,620
It cuts upholstery pieces
For hidden areas,
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00:11:43,620 --> 00:11:46,034
Such as the undersides
Of seat cushions,
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00:11:46,034 --> 00:11:47,448
From the imperfect leather
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00:11:47,448 --> 00:11:50,137
And visible parts
From flawless leather.
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00:11:53,068 --> 00:11:54,793
Once all the pieces are cut,
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00:11:54,793 --> 00:11:58,241
They sew together the back,
Seat, and arms.
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00:11:58,241 --> 00:12:01,896
Then, they stuff
The arms and back.
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00:12:01,896 --> 00:12:04,931
They position the open end
Against a blowing machine
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00:12:04,931 --> 00:12:07,068
That fills it
With polyester fiber.
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00:12:09,172 --> 00:12:12,724
Workers weigh each part
Before and after filling.
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00:12:12,724 --> 00:12:15,275
This ensures they've blown in
The right amount of fiber
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00:12:15,275 --> 00:12:17,172
And that both arms
Have equal filling.
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00:12:27,344 --> 00:12:30,172
Next, they'll fill the seat
With foam.
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00:12:30,172 --> 00:12:32,655
A compression machine
Squeezes it,
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00:12:32,655 --> 00:12:36,275
Then a worker sprays on
Silicone lubricant.
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00:12:36,275 --> 00:12:40,310
This enables the seat cover
To slide on easily.
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00:12:40,310 --> 00:12:42,517
Foam is made
Of a chemical mixture,
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00:12:42,517 --> 00:12:45,206
The formulation of which
Determines the density --
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00:12:45,206 --> 00:12:48,068
The higher the density,
The higher the quality.
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00:12:48,068 --> 00:12:49,931
Elsewhere in the factory,
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00:12:49,931 --> 00:12:52,275
They cut the frame components
From plywood
220
00:12:52,275 --> 00:12:54,931
Using a computer-guided
Band saw.
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00:12:59,310 --> 00:13:02,620
These long pieces
Will form the seat frame.
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00:13:02,620 --> 00:13:05,896
A 3-seater couch
Has 3 separate frames,
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00:13:05,896 --> 00:13:09,620
Enabling each seat
To recline individually.
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00:13:09,620 --> 00:13:14,034
A machine lines one side of each
Piece with steel spring clips.
225
00:13:15,862 --> 00:13:19,793
A worker then dabs the ends in
Glue and assembles the pieces,
226
00:13:19,793 --> 00:13:23,310
Reinforcing them
With long, glue-coated staples.
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00:13:23,310 --> 00:13:25,172
As the staples enter the wood,
228
00:13:25,172 --> 00:13:27,724
Friction-generated heat
Melts the glue.
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00:13:27,724 --> 00:13:31,172
The glue then dries,
Securing the staples.
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00:13:31,172 --> 00:13:34,758
Now comes the step
Known as "Springing the seat."
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00:13:34,758 --> 00:13:38,310
They hook five thick, steel
Springs into the spring clips,
232
00:13:38,310 --> 00:13:41,862
Then hammer the clips closed
To lock the springs in place.
233
00:13:41,862 --> 00:13:45,103
They connect the springs with
A plastic-covered wire so that,
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00:13:45,103 --> 00:13:48,482
When you sit on the seat,
All the springs react in unison.
235
00:13:52,379 --> 00:13:54,896
They assemble the frame pieces
For the arm,
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00:13:54,896 --> 00:13:57,655
Using glue
And glue-coated staples,
237
00:13:57,655 --> 00:14:00,586
Plus a few screws
At strategic points.
238
00:14:00,586 --> 00:14:05,103
They screw the arm to the seat
And begin upholstering.
239
00:14:05,103 --> 00:14:09,241
First, a layer of felt to
Cushion the springs, then wood,
240
00:14:09,241 --> 00:14:13,586
Cardboard, and foam to form the
Rounded shape of the armrest.
241
00:14:13,586 --> 00:14:16,103
After lubricating
With silicone spray,
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00:14:16,103 --> 00:14:19,137
They slip on the leather
And staple it in place.
243
00:14:19,137 --> 00:14:23,310
They upholster the backrest
And sides in the same manner.
244
00:14:23,310 --> 00:14:24,931
The reclining mechanism
245
00:14:24,931 --> 00:14:27,793
Arrives at the factory
With the sides preassembled.
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00:14:27,793 --> 00:14:30,344
Workers install
The connecting pieces,
247
00:14:30,344 --> 00:14:34,172
Then a bushing that reduces
The noise the mechanism makes.
248
00:14:34,172 --> 00:14:37,862
Finally, they install a spring
To control the recline speed.
249
00:14:37,862 --> 00:14:40,448
They screw the mechanism
To the seat frame...
250
00:14:42,931 --> 00:14:45,413
...Then hook up the operating
Handle and test it out.
251
00:14:48,965 --> 00:14:50,793
To cover the back
Of the furniture,
252
00:14:50,793 --> 00:14:54,000
They attach metal tacking strips
To the leather...
253
00:14:56,724 --> 00:15:00,241
...Then turn the edge under and
Hammer the tacks into the frame,
254
00:15:00,241 --> 00:15:04,655
Using a pneumatic hammer.
255
00:15:04,655 --> 00:15:07,275
The last step is to attach
The back to the seat.
256
00:15:07,275 --> 00:15:10,275
There's the detachable flap
At the bottom,
257
00:15:10,275 --> 00:15:12,896
Providing access
To a locking spring inside.
258
00:15:12,896 --> 00:15:16,000
The locking spring
Lets you remove the back
259
00:15:16,000 --> 00:15:19,482
If you have trouble getting
The furniture through a doorway.
260
00:15:19,482 --> 00:15:21,137
At this factory,
261
00:15:21,137 --> 00:15:24,034
Workers are encouraged
To lie down on the job,
262
00:15:24,034 --> 00:15:26,620
But only to inspect
The furniture.
263
00:15:26,620 --> 00:15:29,068
After examining
The fabric and sewing,
264
00:15:29,068 --> 00:15:32,344
They assess the comfort
And test the reclining motion.
265
00:15:32,344 --> 00:15:35,068
Talk about a cushy job.
266
00:15:44,344 --> 00:15:46,793
Narrator: we rip it open
With barely a thought,
267
00:15:46,793 --> 00:15:48,655
More anxious
To read its contents
268
00:15:48,655 --> 00:15:50,034
Than to take a moment
269
00:15:50,034 --> 00:15:52,896
To truly appreciate
Its form and function,
270
00:15:52,896 --> 00:15:56,103
And then
We ruthlessly discard it.
271
00:15:56,103 --> 00:15:59,172
The humble envelope
Just doesn't get much respect
272
00:15:59,172 --> 00:16:03,586
Despite its distinguished
4,000-year history.
273
00:16:09,620 --> 00:16:12,517
As early as 2,000 b.C.,
274
00:16:12,517 --> 00:16:15,310
The babylonians
Baked special clay wrappers
275
00:16:15,310 --> 00:16:16,896
To transport documents.
276
00:16:16,896 --> 00:16:18,206
Eventually,
277
00:16:18,206 --> 00:16:20,517
People made envelopes
From lighter materials,
278
00:16:20,517 --> 00:16:23,275
Such as animal skins and leaves.
279
00:16:23,275 --> 00:16:25,344
By about 1,000 a.D.,
280
00:16:25,344 --> 00:16:27,724
It became the custom
To simply fold a letter
281
00:16:27,724 --> 00:16:29,965
And seal it with a drop of wax.
282
00:16:29,965 --> 00:16:32,724
But everything changed in 1837
283
00:16:32,724 --> 00:16:35,448
With england's new
Penny-postage system.
284
00:16:35,448 --> 00:16:36,896
To mail a letter,
285
00:16:36,896 --> 00:16:40,344
The sender now had to buy
A postage-paid paper wrapper
286
00:16:40,344 --> 00:16:44,103
That folded into an envelope.
287
00:16:51,931 --> 00:16:54,965
One of the many envelope styles
This factory makes
288
00:16:54,965 --> 00:17:00,896
Is a 12-by-18-inch envelope made
Of natural-colored kraft paper.
289
00:17:00,896 --> 00:17:03,275
A machine, appropriately called
The sheeter,
290
00:17:03,275 --> 00:17:07,827
Cuts the roll
Into 21-by-25-inch sheets.
291
00:17:07,827 --> 00:17:11,103
A worker selects the cutting die
For this style
292
00:17:11,103 --> 00:17:13,896
And installs it
On an automated press.
293
00:17:13,896 --> 00:17:17,000
As each stack of sheets
Passes underneath,
294
00:17:17,000 --> 00:17:20,551
The press applies
11 tons of pressure,
295
00:17:20,551 --> 00:17:25,379
Forcing the die right through
Like a giant cookie cutter.
296
00:17:27,241 --> 00:17:30,103
The shaped sheets
Are called "Envelope blanks."
297
00:17:35,379 --> 00:17:36,758
Workers now load the blanks
298
00:17:36,758 --> 00:17:39,310
Into the feeder of an automated
Piece of equipment
299
00:17:39,310 --> 00:17:43,827
Called a blank-sheet
Envelope-folding machine.
300
00:17:43,827 --> 00:17:45,827
As we see here in slow motion,
301
00:17:45,827 --> 00:17:50,413
Revolving steel blades first
Make scorelines, four in all --
302
00:17:50,413 --> 00:17:54,655
One down each side, creating
The envelope's side flaps,
303
00:17:54,655 --> 00:17:57,931
One across the top,
Creating the seal flap,
304
00:17:57,931 --> 00:18:01,931
And one across the lower end,
Creating the bottom flap.
305
00:18:08,000 --> 00:18:11,241
Folding blades hold the paper
Down along the scorelines,
306
00:18:11,241 --> 00:18:13,827
While arms push up
From underneath,
307
00:18:13,827 --> 00:18:17,137
Folding the side flaps
Toward the center.
308
00:18:17,137 --> 00:18:19,000
Just before the flaps meet,
309
00:18:19,000 --> 00:18:22,551
The machine runs a line of glue
Down their edge.
310
00:18:22,551 --> 00:18:25,379
The flaps adhere to each other,
Forming the center seam
311
00:18:25,379 --> 00:18:27,448
That runs down the back
Of the envelope.
312
00:18:30,413 --> 00:18:34,482
The machine then glues the
Bottom flap and folds it closed.
313
00:18:34,482 --> 00:18:35,827
You can see in slow motion
314
00:18:35,827 --> 00:18:38,482
How it also applies glue
To the seal flap at the top,
315
00:18:38,482 --> 00:18:42,862
Keeping that flap open
So that the glue will dry.
316
00:18:42,862 --> 00:18:46,241
The sender has to just remoisten
The glue to seal the envelope.
317
00:18:48,275 --> 00:18:51,068
The finished envelope
Exits the folding machine
318
00:18:51,068 --> 00:18:53,620
And enters another machine
That counts them
319
00:18:53,620 --> 00:18:55,517
And stacks them upright.
320
00:19:05,413 --> 00:19:08,103
This more sophisticated
Piece of equipment
321
00:19:08,103 --> 00:19:12,103
Is called a web-roll
Envelope-folding machine.
322
00:19:12,103 --> 00:19:15,206
They feed the roll of paper
Directly into the machine
323
00:19:15,206 --> 00:19:17,275
And, as we see here
In slow motion,
324
00:19:17,275 --> 00:19:19,103
It does everything
325
00:19:19,103 --> 00:19:23,310
From cutting, scoring, folding,
And gluing the blanks
326
00:19:23,310 --> 00:19:25,344
To counting
The finished envelopes.
327
00:19:25,344 --> 00:19:26,965
For this style,
328
00:19:26,965 --> 00:19:29,137
A die even punches out
An address window
329
00:19:29,137 --> 00:19:30,965
In the front of the envelope.
330
00:19:35,241 --> 00:19:36,724
This all-in-one machine
331
00:19:36,724 --> 00:19:39,517
Goes through all the steps
At lightning speed --
332
00:19:39,517 --> 00:19:41,551
20 envelopes per second.
333
00:19:49,206 --> 00:19:53,068
The thin, transparent film
That covers the address window
334
00:19:53,068 --> 00:19:55,758
Is usually made
Of polypropylene.
335
00:19:55,758 --> 00:20:00,413
The machine cuts it to size
And glues it to the envelope.
336
00:20:00,413 --> 00:20:03,379
This machine
Doesn't have folding blades
337
00:20:03,379 --> 00:20:06,379
To hold the paper down
Along the scorelines.
338
00:20:06,379 --> 00:20:09,551
Instead, the blanks roll through
A series of rotating cylinders
339
00:20:09,551 --> 00:20:11,103
With air holes.
340
00:20:11,103 --> 00:20:15,034
A suction system vacuums
The blank to the cylinder
341
00:20:15,034 --> 00:20:17,413
While the operation
Is being performed,
342
00:20:17,413 --> 00:20:18,862
Then releases the vacuum
343
00:20:18,862 --> 00:20:21,448
To transfer the paper
To the next cylinder,
344
00:20:21,448 --> 00:20:25,172
Where it's vacuumed on for the
Duration of the next operation.
345
00:20:29,862 --> 00:20:33,448
Internal-mail envelopes are
Opened and closed repeatedly,
346
00:20:33,448 --> 00:20:36,379
So they don't have a
Lick-and-stick seal flap
347
00:20:36,379 --> 00:20:38,379
Like regular envelopes do.
348
00:20:38,379 --> 00:20:41,241
As we see here in slow motion,
349
00:20:41,241 --> 00:20:43,862
An automated machine
Rivets a cardboard button
350
00:20:43,862 --> 00:20:46,517
To the back of the envelope.
351
00:20:46,517 --> 00:20:48,413
At the same time,
352
00:20:48,413 --> 00:20:51,758
It rivets another button, with
A piece of string, to the flap.
353
00:21:00,000 --> 00:21:04,172
Envelope factories use
Many different types of paper,
354
00:21:04,172 --> 00:21:07,206
From top-quality vellum
To kraft paper.
355
00:21:07,206 --> 00:21:08,965
With printing equipment
356
00:21:08,965 --> 00:21:11,344
Incorporated
Right into the folding machines,
357
00:21:11,344 --> 00:21:15,655
They can print return addresses,
Even elaborate custom designs.
358
00:21:22,275 --> 00:21:24,517
If you have any comments
About the show,
359
00:21:24,517 --> 00:21:27,068
Or if you'd like to suggest
Topics for future shows,
360
00:21:27,068 --> 00:21:29,310
Drop us a line at...
29355
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