All language subtitles for S05E01 - Paving Asphalt; Marshmallow Cookies; Loudspeakers; Electronic Door Locks (576p AMZN WEB-DL x265 Garshasp)_track4_[eng]

>> narrator: today on

"How it's made"...

Paving asphalt...

Marshmallow cookies...

Loudspeakers...

And electronic door locks.

Asphalt is a black, liquid

Substance that's a by-product of

Processing crude petroleum.

Asphalt is a key component of

Waterproofing and insulation

Materials and roofing shingles.

But its best-known use is for

Paving roads.

Asphalt cement is a by-product

Of crude oil -- the key

Ingredient they mix with crushed

Rocks and other minerals to make

Paving asphalt.

So, production begins at the

Paving plant's quarry, where

Some 50 feet below ground,

Workers driving heavy machinery

Collect boulders of granite that

Have been blasted off the rock

Walls.

Trucks transport the rocks to

The paving plant, which is right

On the quarry site.

They dump their cargo into the

Primary crusher -- a machine

Whose steel jaws crush these big

Rocks into pieces smaller than

8 inches.

It takes mammoth force to crush

Solid rock.

The fly wheels that amplify the

Motor's energy weigh more than

6 tons.

The primary crusher empties onto

A mobile conveyor belt, which

Transports the crushed rocks

To an outdoor storage area.

When it's time to make the

Asphalt, the rocks travel, via

Conveyer belt, from the storage

Area to a screening building to

Be classified by size.

There, the rocks tumble

Downward over a series of

Inclined screens whose largest

Holes are 4 inches wide.

What's too large to drop through

Goes to a secondary crusher,

That reduces the rocks to

4 inches or smaller, then sends

Them to a third, or tertiary,

Crusher that further reduces

Them to 1 inch or smaller.

What's small enough to pass

Through the screens bypasses the

Secondary crusher and goes

Directly to the tertiary

Crusher.

After this last crushing stage,

The largest stones are 1 inch

In size.

Everything smaller than 1/4 inch

Goes in one pile -- that

Includes stone dust created by

The crushing process.

Stones that are 1/2 to 3/4 of an

Inch go into another pile...

Stones 1/4 to 1/2 inch into

Another.

Trucks transfer material from

Each pile to separate

Compartments called feed bins.

Exactly what goes into the

Paving asphalt depends on what's

Being paved.

But, generally, these are the

Four ingredients...

Sand...

Stone dust...

1/4- to 1/2-inch stone...

And 1/2 to 3/4 of an inch stone.

The ingredient proportions vary

According to what the paving

Asphalt will be used for.

Stones, along with sand and

Stone dust as fillers, usually

Make up about 95% of the mix.

The remainder, added later, will

Be liquid asphalt cement.

Each bin releases a specific

Amount of material onto a

Conveyor belt running under it.

The belts lead to a main

Collecting belt that dumps

The ingredients, combined,

Onto yet another belt that leads

To a drier.

The drying process, which takes

About a minute, removes all

Traces of humidity.

This will enable the materials

To bond better with the asphalt

Cement.

Screening equipment then

Reseparates the dried

Ingredients, making it possible

To precisely weigh out the

Required amount of each one.

Everything then goes into a

Mixer.

As this demonstration shows, the

Mixer blends everything

Thoroughly.

Then it's time to pump in hot

Asphalt cement.

Oil refineries make asphalt

Cement from what's left over

After they've processed crude

Oil.

The paving mix contains about 5%

Asphalt cement.

This is what happens inside the

Mixer.

The hot asphalt cement binds the

Ingredients in about 30 seconds.

The result is ready-to-lay

Paving asphalt.

The mixer empties directly into

Trucks destined for the paving

Site.

There, a paving machine will

Spread the hot asphalt on the

Road bed.

Then a compactor roller will

Pack it down.

The asphalt cools and hardens in

About one hour, depending on the

Weather.

>> narrator: the next time you

Bite into a marshmallow cookie,

You can thank the ancient

Egyptians.

They invented marshmallow

Candy by thickening honey with

Sap from the root of the

Marshmallow plant -- a herb that

Grows in salt marshes and along

Large bodies of water.

Modern marshmallow contains

Gelatin instead of sap from the

Mallow root.

The snap test -- to make sure

The coating is hard and thick

Enough.

Then, the taste test.

If you've got a sweet tooth,

Doing quality control in the

Marshmallow cookie factory is

Your dream job.

To make a batch of dough for the

Cookie base, they mix wheat

Flour, salt, baking soda and

Powder, cornstarch, whey powder,

And potassium sorbate.

Then they add several liquid

Ingredients.

This one causes a chemical

Reaction, making the biscuit

Lighter.

This cream-colored liquid is

Vegetable oil shortening.

This transparent liquid is

Glucose fructose, a sweetener.

The ingredient proportions are

Also a company secret.

From the mixer, the dough goes

Into a machine called the

Chipper.

It shreds the big blob into

Pieces about the size of the cap

On a highlighter pen.

This makes the dough more

Manageable for the next machine,

Called a rotary mold.

Inside that machine, a large

Roller flattens the dough

Pieces, forming them into a

Dense sheet about 1/2 inch

Thick.

It then presses the sheet

Against another roller whose

Surface is a cookie mold.

The factory uses the rotary mold

Machine for many different types

Of cookies.

It simply installs the

Appropriate roller for the

Cookie in production.

For marshmallow cookie bases,

The mold cavities are round.

The bases exit the rotary mold

And make their way onto a moving

Baking sheet.

That transports them to an oven.

The baking time and temperature

Are, once again, top secret.

The baked cookie bases exit the

Oven and move onto a conveyer

Belt that transports them to a

Cooling area.

Once they cool to room

Temperature, the bases go into a

Machine called the base feeder.

It lines them up like marching

Soldiers to receive their

Marshmallow filling and

Chocolate coating.

The process does require

Military precision.

Factory technicians have to

Adjust this machine daily to

Ensure accuracy to 1/32 of an

Inch.

A portion of filling has to land

Perfectly centered on each base,

Finishing off in a curled peak,

This brand's trademark.

The company won't divulge how

Much marshmallow filling goes

Into each cookie, nor will it

Reveal its marshmallow recipe.

But marshmallow is usually made

From either corn syrup or sugar

And gelatin.

And now for the final layer --

The chocolate coating.

Not only are the marshmallow and

Base covered in hot, melted

Chocolate, the base floats in

It, which coats the underside,

As well.

Built-in air jets blow off the

Excess.

The chocolate hardens inside a

Cooling tunnel.

How long that takes in the

Tunnel temperature are -- you

Guessed it -- classified

Information.

As the cookies exit the cooling

Tunnel, a quality-control worker

Does spot-checks to ensure the

Coating is thorough, hard

Enough, and thick enough.

On the packaging line, the

Cookies go into plastic trays.

To keep up to speed, the workers

Have to grab four cookies in

Each hand without breaking the

Coating.

The trays pass through a machine

That wraps them in plastic film.

This keeps the cookies fresh and

Also prevents them from falling

Out of the tray.

Meanwhile, another machine

Assembles the boxes -- first

Folding and gluing one end shut.

Once workers load the trays, the

Machine glues the open end

Closed, as well.

Then with the go-ahead from

Quality control, the box's next

Stop is the cookie aisle of your

Local supermarket.

>> narrator: loudspeakers take

An electrical signal and turn it

Into sound.

The key to it all is a magnetic

Wire voice coil and a permanent

Magnet that attract and repel

Each other.

As the coil moves back and

Forth, it rapidly vibrates a

Flexible cone.

This vibrates the air in front

Of the speaker, creating sound

Waves.

Loudspeakers contain at least

Two magnet-and-cone assemblies

Known as drivers.

They're typically housed in a

Box called a speaker enclosure.

To build the internal magnetic

Structure, the factory begins by

Cutting two plates of iron, each

About 1/2 inch thick.

They go one at a time onto a

Lathe.

First, the machining tool

Smoothes and evens out the

Surfaces, getting rid of the

Marks the saw made.

Then it cuts out a small hole in

The center of one plate and a

Larger hole in the center of the

Other.

Next, they cut a smaller and

Thicker round piece of iron

Called the core.

A reamer bores a large hole

Through it.

They apply superhigh-strength

Epoxy glue to the core and to

The back plate -- the plate with

The smaller hole.

They glue and screw the pieces

Together because the bond has to

Be strong enough to withstand

Intense magnetic pull.

They glue a foam filter in the

Hole to ensure the vibrating

Cone doesn't draw in dust and

Cause internal damage.

Now they spread the glue on the

Narrow end of what's called the

Metal basket, a die-cast

Aluminum frame that will hold

The magnetic structure and cone.

They screw the front plate, the

Plate with the bigger hole, onto

The glued surface.

Then they glue the underside of

The front plate and one side of

A ferrite, a ceramic ring made

From the iron powder.

After adhering the ferrite to

The front plate, they apply glue

To the other side of the

Ferrite, then flip the basket

Over to attach the back plate.

The core fits through the large

Hole in the front plate.

They insert shims to center it

While the glue dries.

After screwing terminals to the

Basket, they put the entire

Structure they've just assembled

Into a magnetizing machine with

600 volts of direct current.

The machine creates positive and

Negative poles, transforming the

Magnetic structure into a

Permanent magnet, meaning it has

A constant magnetic field around

It.

Now they wind the voice coil --

The electronic magnet that will

Interact with the permanent

Magnet.

An electromagnet is an

Object that generates a magnetic

Field only when there's a

Current running through it.

They wind enamel-insulated

Copper wire, gluing it to a

Rigid plastic sheet.

The positive pole of this

Voice coil will be attracted to

The negative pole of the

Permanent magnet.

The negative poles will repel

Each other.

The key is that the voice coil's

Poles are constantly reversing

Position because the electrical

Current running to the speaker

Is an alternating current,

Meaning it switches between a

Positive and negative charge

Several times per second.

This makes the magnets attract

And repel each other

Continuously, causing the

Voice coil to move back and

Forth rapidly.

This vibrates the cone, which

Creates sound waves.

After slipping the voice coil

Between the front plate and the

Core, they glue on the bottom

Suspension -- flexible fabric

Rings that move with the

Voice coil and prevent it from

Rubbing on the magnetic

Structure.

Next, they glue the cone.

It's usually made of cardboard,

Plastic, or metal.

Then solder the electrical

Connections.

The current coming from the

Amplifier travels by wire to the

Two terminals.

The terminal wires connect to

The voice coil wires.

After making sure the cone moves

Freely without rubbing, they

Glue on a rigid cardboard cap

To keep out dust.

The last step is to take the

Speaker for an audio test drive.

They connect it to a machine

That transmits different

Frequencies.

They make sure the movement of

The voice coil and cone isn't

Obstructed in any way.

Then a computer device analyzes

The sound wave the driver sends

Out.

Two-way speaker systems have two

Drivers in each enclosure -- a

Woofer and tweeter.

A woofer has a large cone that

Vibrates more slowly for low

Frequencies.

A tweeter has a small cone that

Vibrates quickly for high

Frequencies.

Three-way systems have a third

Driver with a medium-sized cone

For the midranges.

>> narrator: at most hotels,

Room keys are a thing of the

Past.

You're more likely these days to

Be given a key card.

When you arrive at the door to

Your room, you swipe or insert

It to unlock the handle and get

In.

Because the room number doesn't

Appear on the card, this system

Is far more secure than door

Locks with a keyhole.

The metal case that houses the

Door lock's mechanical and

Electronic components is called

The housing.

To make it, they begin by

Melting zinc ingots.

To melt zinc, you have to heat

It to about 734 degrees

Fahrenheit.

Die-cast machinery then injects

The molten zinc into molds.

Between injections, sprayers

Coat the empty mold cavities

With a release agent, the

Industrial equivalent of

Greasing a baking pan.

A built-in cooling system

Hardens the metal.

Then a trimming die cuts off

Excess zinc around each piece

And in the openings.

Meanwhile, the electronic

Circuit board, the brain of the

Lock, takes shape.

They call this the "Pick and

Place" machine.

It picks up the 60-odd

Electronic components and places

Them in the right position on

Each board.

This computer-guided machine

Installs 15,000 components per

Hour.

Next, the boards undergo what's

Called wave soldering.

A mix of molten lead and tin

Surges up from underneath,

Fusing components in place and

Creating electrical bonds.

Then, both sides of each circuit

Board get a coat of

Silicon-based sealant.

This protects the components

Against the elements.

Back to the housings now.

Workers lubricate them with

Grease and apply what's called a

Sleeve bearing -- a nylon

Bearing that enables the handle

To turn smoothly.

Next comes the drive tube onto

Which the lever will be

Assembled on the other side.

There are several clutch

Components that link the lever

To the latch.

Swipe the right card, and they

Permit the latch to retract.

After applying more lubricant,

They install an override that

Enables the hotel to open the

Door with a key, if, for some

Reason, the electronics

Malfunction.

They install the circuit board

And connect it to the various

Parts it controls, such as the

Clutch motor, which they install

Next.

Now they close up the completed

Housing with the steel

Back plate.

This protects the components

Inside from rusting.

The last step is to insert a

Battery pack.

It holds three standard double-a

Batteries.

The factory tests the lock using

A test key card because the lock

Isn't yet programmed to work

With a specific card.

That's done after installation.

Elsewhere in the factory, they

Assemble the mortise -- the part

Of the lock that goes inside the

Door.

When you lock up, the mortise's

Bolt comes out of the door's

Edge and fits into the hole of a

Receiving piece, called a strike

Plate, in the door frame.

They close up the mortise with

The back plate.

This demonstration shows how

They install the mortise in the

Door.

Once it's in, they screw a

Decorative plate on top.

This is what the finished

Electronic door looks like.

Key cards have instructions on

One side, a magnetic data stripe

On the other.

They use a generic card to test

Every lock that comes off the

Production line.

In the quality-control lab, they

Subject every new design to

Several rigorous tests.

They open and close 1 million

Times.

They subject the lever, latch,

And lock to repeated impacts.

They also test lock function in

Extreme temperatures.

These electronic door locks come

In several metal finishes plated

Over the zinc and even in a

Painted finish that simulates

Wood.

If you have any comments about

The show, or if you'd like to

Suggest topics for future shows,

Drop us a line at...

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