Original subtitles

Forged in fire and cast in steel...

It's big, it's huge, it's intimidating.

...giant metal machines are engineered to make

human efforts at work and play easier.

It's like a monster.

Metal touches every aspect of human life,

from trains and ships to factories.

It is a part of building bigger and better technology

to keep our world turning.

London, England is home to the oldest

and one of the largest subway systems in the world...

...the London Underground.

We are now one in every ten journeys in the UK.

Millions of tons of metal twisted

into an intricate labyrinth of rails.

- It's like a monster. -Hundreds of trains,

seemingly endless amounts of track

and a multitude of stations.

WOMAN (Recorded:) This is an Elizabeth line service

to Sheffield.

Moving over 1.3 billion riders each year.

It's about six million customer journeys a day,

so it's a busy, busy network.

Transporting people seamlessly beneath the city.

No separate access available at Harrow on the Hill station.

Never a dull day here.

But to keep it going...

We're ready to race.

...takes constant maintenance and repairs.

The London Underground subway

is this giant machine. It's a huge network of tracks

moving incredible amounts of people every minute of the day.

WOMAN (Recorded:) The next station is Liverpool Street.

But this 400-kilometre system

comes from humble beginnings.

The London Underground is old, and to put it in perspective

of just how old it is, think of it this way.

The subway system was built before the automobile,

even before the light bulb.

In fact, Abraham Lincoln was the President of the United States

when the London Underground

first opened its doors. That's crazy.

In 1860, London, England

was the largest city in the world,

with a population of over three million,

and nearly a quarter million people commuted by bus,

rail or on foot each day.

To relieve the congestion,

the trains were moved underground,

resulting in the world's first subway.

The London Underground was first constructed using

the cut-and-cover method,

where a trench was dug along the streets

and then covered over.

The initial trains were gas-lit

wooden carriages hauled by steam-powered locomotives.

They burned coal

to heat the water in a boiler to create steam.

Along with steam,

it created a ton of air pollution.

To eliminate the pollution and improve

the overall efficiency and reliability of the service,

the London Underground began shifting

to electric power in the 1890s.

And by 1905, the entire network was electrified,

including the locomotives.

Today, the network

is an integral part of daily life in London.

So, it's approximately five million customer journeys a day

on the London Underground network.

If you look at that for the whole of the United Kingdom,

that's more than all of the other mainline

train services combined.

Good afternoon.

This is James at the London Underground Control Centre

with a network information broadcast.

The biggest challenge is keeping the Underground

running smoothly and on time.

Any downtime or delays can cause a snowball effect

throughout the system.

So, even when things

seem to be running smoothly on the tracks,

the potential for trouble is always brewing.

So the only other option we have is to suspend it so that we can put a good train at Mill Hill.

Push this one past towards Mill Hill, so it's there.

We've got a train that's broken down at this station.

We had two trains stuck behind it,

which had customers on board.

And now, we're looking at how we can recover this train.

No set free access available at Harrow on the Hill station.

This is due to a customer incident.

Never a dull day here.

Yesterday, we had a person that wasn't breathing on a train.

We had a CPR ongoing because of that situation.

We couldn't move the person from the train,

so the line was suspended.

And when things go wrong, things build up really quickly.

Woman over PA: Train out of Platform B

with service to Reading... Platform B, Reading.

-Prime Whiskey-7-8.

What have you done there?

We've done... shut the doors.

We shift a lot of people, up to 800,000 people a day.

So, a three-minute delay down here can be catastrophic.

So, our next station is Bond Street.

Of the 11 subway lines in the London Underground,

the Elizabeth Line is the busiest,

transporting nearly a million riders

along its 118-kilometre track every day.

With the introduction of the Elizabeth Line,

we are now one in every ten journeys in the UK.

So, we are the most frequently used train in the UK,

and that's from Scotland, all the way down to in London.

This system is the backbone of London Transit.

And it takes a significant beating.

We're going into the shed

because this train is due planned maintenance.

All that bumping and grinding on the tracks

results in a constant flow of repairs

for depots across the city,

like here at Old Oak Common.

Okay, your route should be coming up shortly for you.

MAN Thank you.

On a 12-hour shift,

roughly between midnight and midnight,

we could have over 100 train moves.

I think it's something like 112 trains arriving and departing.

So, it can get pretty busy.

Each line of the London Underground

has at least one maintenance depot to service

and maintain its trains overnight.

There are 14 depots throughout the system

to address the variety of challenges that come

with such heavy use.

So, this is old O'Connor depot.

We do all planned preventative maintenance, which is our exams,

all the way through to corrective repairs.

So, this is the sole location

to maintain the Class 345 Elizabeth Line fleet.

It all starts

with the Automatic Vehicle Inspection System,

or AVIS for short.

As the train rolls into the depot,

the AVIS uses special cameras, lasers, and thermal imaging

to scan every component of its structure,

from the roof and body, to the wheels, brakes, and axles.

It collects data on the condition of the components,

anticipating problems before they occur.

Once the train has cleared the system,

AVIS details the repairs needed,

optimizing maintenance.

AVIS is like a doctor scanning your entire body

and doing every test

all at once to see how healthy you are.

So, you can see AVIS building has now illuminated.

So, this section here we're coming into takes photographs

of the outside of the trains.

There are two AVIS sheds, with washers,

processing 35 trains per day -

half of the Elizabeth Line fleet.

They allow the team to stay on top of maintenance and address

potential issues before they lead to breakdowns.

But the AVIS doesn't stop there.

And the lasers below,

they'll be measuring the brake pad thickness.

Getting this kind of intricate report helps maintenance crews

to plan out repairs that are needed for the fleet super fast.

Before the AVIS,

a train would be manually inspected

once every month.

But now, maintenance technicians scan

and even wash the train in about five minutes.

It's done every time a train comes back onto depot.

They go through AVIS and the wash.

So, every 48 hours, roughly, we get every train back to depot.

However, not everything is a quick fix.

When there's more significant damage or maintenance is needed,

it calls for major overhauls.

The Elizabeth Line is the busiest

of all the London Underground lines.

Collectively, trains on this line

travel over 32,000 kilometres a day.

That causes a lot of wear on the trains,

especially on the bogies.

Bogies are sets of four wheels

attached to each axle of the train car.

When these bogies travel along the twists and turns

of the tracks, the outside wheels wear differently

than the ones on the inside.

That uneven wearing can cause big problems.

So, like rotating the tires on a car,

these wheels have to be moved to different positions, too.

MAN Have my permission

to pass the stockyards and enter the shed on line 9.

- Understood.

So, we're coming into Road 9, Maintenance Road 9.

This road is specifically designed

to be able to lift this train up into the air.

This track leads to the synchronized jacking system,

where 36 high-pressure hydraulic cylinders lift

all nine cars of the 200-meter-long train,

giving maintenance workers access to the bogies.

About 50 meters to go still.

Changing the position of the wheels is a major job,

which starts by lining up the trains anchor points

with the jacks.

MAN Okay, slow down, James.

Five, four, three,

two, go in.

Lovely.

Lovely.

So, we're just putting in the last jack to move up the train.

Okay, we're ready to race.

JAMES Yeah, in position.

Okay, going to start lifting now.

Each hydraulic jack is connected

to a central computer-controlled unit

that ensures all the jacks are synchronized while lifting

or lowering the train.

Lift complete.

The next step is to rotate

the bogies as fast and as safely as possible.

Enter the bogie drop -

a custom-made system

that carries bogies down through the floor,

along a conveyor, and back up to the waiting train.

Today, we're rolling the bogie onto the bogie drop.

From a bogie workshop, we're going to be dropping it down

and round onto a Mike-7, ready to fit to another train.

If my leading axle or wheelset has hit, you know, a tree branch

or something like that and it's made the wheelset defective,

we can utilise the bogie drop to replace that wheelset

within maybe an hour.

Going to drop down to the bottom of the bogie drop.

Going to traverse across around 30-40 meters.

So, this is a brand new system for this depot.

And then, come back up

in line with the rails in front of that train.

The new Old Oak Common Depot opened in 2018.

It's a transport super hub, capable of servicing 70 trains.

We can do maintenance

in a lot more timely fashion...

...than other depots that are older

because we have the better equipment on our site,

which is really good.

Just as important as the trains,

the tracks also need continuous upkeep

due to the relentless pounding they take.

The fact of the passenger trains going over

just constantly, literally just grinding down

the profile of the track, normally,

it happens more over to one side if you're on a corner,

where the train will ride up

and it will take out the curve of the rail over constant use.

Back in the old days of the Underground,

when it first opened, the workers had to walk the tracks

and visually inspect the rails to check for any damage.

The workers used hammers to strike the rails

and listen for unusual sounds,

and then use the manual grinding or filing tools

to remove all the surface irregularities.

Or even worse, having to cut out the defective part

and weld in a new section by hand.

But today,

it's a much more technologically advanced endeavour.

When the London Underground shuts down for the night

and the city goes to sleep,

the work of the rail milling train begins.

- Okay, on the move.

So, we always mill overnight. We don't mill during the day.

Otherwise, it can disrupt the passenger train services.

Before the rail milling train can get started,

a series of safety checks must be completed.

TPWS and AWS operational.

So, it's now in work mode

and Marcin can test out

all the equipment's working as it should be.

And we'll be able to operate the milling machine.

- Ready to drop down.

Every night we have to simulate the operation.

To check the machine is actually operating as it should before,

because on the shift, there's not time to fix that.

Right.

Basically we have to ensure that the machine is faultless.

I'm looking now at the Eddy current system

to make sure that there's no springs or anything broken,

all the cylinders are in the correct places,

making sure there's nothing physically damaged.

I'm just checking the polishing unit and the grinding unit.

Sometimes, after constant use, you get some damages

along the edges there

and up the top there where the grinder dust is going through.

When the tests are complete,

the rail milling train gets the okay

from dispatch to head out.

- Okay, releasing the brakes.

But this incredibly advanced machine

only has a four-hour window

to complete its work before the subway reopens.

The rail milling train

restores the rails to their correct profile,

reducing wear on both the wheels and the tracks.

Okay, grinders on 62 and 10 speed.

Correct profile means the cross-section

looks like it should, that if you looked on it straight on,

it's just the right shape.

Guided by magnets and lasers

that scan the tracks for problems,

the first task of the rail milling train

is to smooth out the rails by shaving them

with metal brushes and carbide shears,

essentially cutting out deep wear,

cracks and surface dents.

If you've ever been on a subway

and heard that screeching sound

during a curve...

...you'll appreciate the importance

of these grinding units.

So, we've got a total of six milling heads on our unit here.

They're interchangeable

and on the heads, you've got rights and lefts,

and it's critical that they go on the right one.

Otherwise, it will cause damage to the milling head

and the rail head surface.

We had a batch of older, like, teeth,

as we call them, which are on the milling heads.

They were only lasting 400 to 500 meters,

but we've had over a thousand meters on these new heads,

so they are much better and much more efficient.

Just let me know when the radio is on channel three

because the camera is a bit dark.

Overnight, alone in the Underground,

the work of this team is invaluable

for the lives of millions of riders.

If mistakes are made during the rail milling process,

it can be catastrophic for commuters.

Just felt a bit of jumping there, mate.

Okay.

A bit of the bogie steering jump.

Just keeping an eye.

I didn't see nothing on the camera though, mate.

Yeah, if you're not careful when you do cut the track too deep

or for whatever reason, depending on the severity

of the damage to the rail, it could cause derailments.

So, it's really important, obviously,

you concentrate on what you're doing.

The London Underground,

like all rail systems, has a history of derailments.

So, the importance of the overnight milling train

and maintenance crew

to keep this massive transport system running smoothly

and safely cannot be understated.

To make sure that things run on time and not have accidents,

we need to see where defects are and identify them for repair.

Next, the milling train polishes

and buffs the rails, so they make better contact

with the wheels of the train.

The engineering that's gone into this machine is unreal.

And it's really-- it's a--

it's a big machine and it's capable of doing great things.

Yeah, profile's all good, mate.

Longitude's good and the trans is good as well.

Finally,

with the track maintenance complete,

the milling train returns to the depot.

Now that the night has ended and the sun rises over the city,

the London Underground is ready to open its gates

and do it all over again.

The London Tube is the GOAT of transit systems.

It's the reason that we have subways around the world.

And so, it's so exciting because it's where the idea came from.

It's the first people to say,

"We should run trains underground

"and it would make better transit for our system."

London sets the example for what you can do

if you build a city connected to really good transit.

With miles of gleaming rails

and fleets of trains in motion,

it truly is one of the world's mightiest metal machines.

This is the Carnival Celebration.

It's more than one of the world's biggest cruise ships.

This is a self-sustaining home away from home

for its 6,500 passengers,

transporting them from port to island port.

It's a floating city.

The Celebration is a floating oasis,

bringing the comforts of a city to the open seas.

Coming in at nearly 200,000 tonnes,

this massive steel hull

has 19 decks for guests and entertainment,

as well as crew and the many engines,

machines and parts that keep this cruise on course.

And this travelling paradise would not be possible

without liquid natural gas -

the lifeblood of the Celebration.

As the name would imply, natural gas is a gas.

But it's hard to transport

because it takes up so much space.

If you take that natural gas

and cool it down really, really,

really cold, it turns from a gas into a liquid

that can then be transported anywhere in the world you want.

But a ship this size, using specialized fuel,

can't just pull up to the pumps.

The pumps need to pull up to it.

So, this is a barge that was specially built to carry

liquefied natural gas.

These purpose-built barges store

and transport the equivalent

of nearly four million litters of fuel -

enough to refuel two massive ships

headed for a seven-day cruise.

This ship can hold

approximately 3,500 cubic meters.

It is brought down to approximately

170 degrees negative Celsius

or around 280 degrees negative Fahrenheit.

The cryogenic state of liquid natural gas

is so important for the storage needs of the ship.

It saves a tremendous amount of space.

Bridge fire patrol from LNG station everything is fine.

Once on board, the LNG is used to power the motors

and generators that provide energy

for everything necessary

to keep the guests comfortable in transit.

O-25.

Up above, it's a vacationer's paradise.

But below deck, it's a mechanical maze of machines,

cables and pipes that connect to every component of the ship.

The engine room,

it's all the way from the aft of the ship to the forward.

Below the waterline on Deck Zero

is the beating heart of the Celebration -

the place where all that fuel is transformed into power

for each of the ship's operating systems.

This is the motor and this is the generator.

The difference

between the motor and the generator

is that the motor produces mechanical power,

just the movement.

The generator converts the movement in electrical power.

To power these four enormous engines,

liquid natural gas is converted back to its original form - gas.

Inside the engine,

the gaseous fuel is then mixed with air

and introduced to a pilot fuel that ignites,

creating combustion.

The resulting pressure pushes down on the pistons,

creating a powerful movement.

All four generators power up the network.

Without this, we will not run anywhere.

The ship is a piece of steel.

With no power, no electricity, no light, no water, nothing!

When the power is flowing,

it's the ship's state-of-the-art propulsion system

that keeps this floating oasis alive and moving on the water.

My name is Vincenzo Alcaras.

I am the captain of the Carnival Celebration.

This ship is a little bit different

from any other traditional ship because it is a pod ship.

Historically, ships relied on simple tools

to navigate the open waters,

from the sun, moon and stars to compasses, sails and runners.

But boat steering systems

have undergone significant modernization,

propelled by advanced technology,

leading to the introduction

of azimuth pod systems for cruise ships in the late 1990s.

What you'd expect to see on a boat is a fixed propeller

and a rudder right behind it.

Now, what the pod does

is move that propeller and the rudder kind of into one thing.

The propeller itself will push the ship

in whatever direction it needs it to go.

Azimuth pods are a gearless steerable

propulsion system where the motor is housed within the pod,

outside the ship's hull.

They allow huge ships, like the Celebration,

to navigate narrow waterways

with the ease of a much smaller vessel.

This advanced technology

can rotate 360 degrees, providing unparalleled control

over the ship's direction and speed.

It's a revolutionary propulsion system that allows massive ships

to manoeuvre with incredible precision and efficiency.

Once in open water, this ship is designed

to be an island unto itself, responsible for the lives

of every guest and every crew member on board.

The Carnival Celebration is a cruise ship

that carries thousands of people.

As soon as the ship leaves the dock,

there's no connection to shore.

Even though it's surrounded by water,

freshwater is the key to survival at sea.

The earliest European sailors used barrels laced with alcohol

to keep algae from growing on their supply.

And the most important task whenever a ship reached land

was to replenish its freshwater stock.

In the 1700s, distillers were introduced to ships

to create freshwater through evaporation.

And then, in the 1980s, reverse osmosis systems

were added to desalinate water.

These are our freshwater generators.

This equipment

is taking water from the sea

and producing freshwater.

Onboard, we are keeping 4,500 cubic meters of water,

which is approximately 1,200,000 gallons,

to supply the water to our ship.

These four water generators produce enough water

to fill and maintain the equivalent

of nearly two full Olympic-sized swimming pools.

The Celebration draws ocean water into the vessel

that makes its way through a reverse osmosis system.

There, tubes force the water through a multi-layered membrane

that allows small water particles through,

but filters out salt and impurities.

Then, the resulting freshwater is re-mineralized

and chlorinated for use

throughout the network of the ship.

Without this equipment, we will not have the water

for taking a shower, we will not have the water for laundry,

for flushing the toilet.

While saltwater is readily available,

it is a hard mineralized water

that would corrode and ultimately destroy

the ship's plumbing system.

Those are one of the vital equipment onboard the ship.

All the water for the ship is provided by this system

and the freshwater pumps

that send potable water to every deck, sink, faucet,

and facility.

After solving the problem of potable water,

engineers got to answer some more unique questions.

Like, how can a ship turn water into beer?

I am the brewmaster on the ship.

Everything from grain to glass,

ordering to serving, all falls on me.

I can control everything

from water flow to the brewing process.

The soft remineralized water of the ship is less heavy,

making it ideal for brewing several styles of beer.

Without that desalinization process

and without being able to pull that water in,

we would not be able to make the beer we make on the ship.

It takes a lot of water to make beer.

On average, the brewery makes

1,000 litres of beer a week,

which takes 5,000 litres of water to accomplish -

a fraction of the freshwater produced by the ship,

but it's very appreciated.

The only place you're gonna get this beer

is right here on this ship.

The demand for beer is high,

but nothing beats the demand for food.

And ferrying from port to port,

packed to the brim with necessities,

doesn't leave a lot of room for food waste.

We're working very hard to reduce food waste

in general from our ships, because food waste

is a large contributor

to greenhouse gases around the world.

A ship of this size can carry around

300 tons of food, and 30% of that

could be wasted during a vacation.

In the pursuit of efficiency and sustainability,

technology is helping this ship stay on course.

So, in our efforts to try to reduce food waste

onboard the ships, we're integrating AI technology,

so that we can actually scan what is left on the plates

that come back from the tables.

The AI tracks the weight

and food type of the leftovers to determine

if the culinary team should change the menu

or portion of food being served.

Hey. How you doing?

It's an innovative solution,

reducing food waste and food storage needs.

This is a biodigester. We take food waste

from around the ship, and we add beneficial bacteria,

and some bio media,

and the bacteria, they digest the food waste

that's left on people's plates,

and what comes out is the water that we use

to just flush the drain.

With a mixture of microbes and enzymes,

this specialized equipment digests most food products

and even bio-plastics within 24 hours.

Our biodigesters are critical to us because it allows us

to dispose of the food waste that's on board.

And biodigesters drastically reduce the need

for incinerators and bulk waste systems

that take up valuable deck space.

Behind the scenes, it's our job to make sure

that we're addressing any kind of environmental impact.

Through food waste management

and water and waste recycling systems,

the Celebration, along with the 29 ships

of the Carnival cruise fleet divert nearly 9,000 tonnes

of waste materials from landfills every year.

So, it's important to remember

that this is a floating city

because most resorts aren't making their own electricity,

they're not generating their own potable water,

and recycling them, like we are on board.

The Celebration is a beacon of efficiency

and innovation,

ushering thousands of people

to and from their dream vacations annually,

a metal marvel on the high seas.

crui,

to construction machines,

to mining equipment...

...Caterpillar keeps some of the biggest

vehicles in the world moving.

These machines, they're a work of art.

They're massive monster machines.

These mammoth off-road trucks

stand two stories tall.

I mean, I'm big, but this is real strong right here.

And they're engineered to haul 363 tonnes of cargo

through some of the toughest terrain on the planet.

There's nothing like this that exists.

These trucks are born in a high-tech factory

in Middle America...

We have the biggest of the big, right here in Decatur, Illinois.

...where robots and humans work in harmony

to bring these behemoths to life.

This is the start of something big.

These trucks have to be big

to move the vast amounts of material

needed in modern mining.

Mining trucks are so enormous

that they have to be built in segments.

For example,

the frame of the 797 truck

starts with nine separate pieces or castings.

We have some of the most advanced welding equipment,

machining equipment,

and also assembly equipment that's on the planet Earth.

The nine castings will form the backbone

of the Caterpillar 797 haul truck.

They are locked in place with hydraulic clamps.

These hydraulic clamps are so strong,

strong enough to hold a 90,000 pound truck in place.

Once the pieces are clamped,

they're ready for tack welding,

which joins the pieces temporarily.

Then, giant cranes heft the assembled

40,000-kilogram frames

and lower them into place on the rollover station.

DR. EL-SAYEGH: The rollover station is a giant

rotation mechanism, almost like a rotisserie.

It has enormous hydraulic power

that holds the tacked frame in place

and can rotate it 360 degrees.

We have nine rollovers

in this one line here in this building,

and each one of them rotate 45 to 90,000-pound truck

360 degrees, so my operators can weld on them easier.

It's like buttering a corn on a cob.

Before rollover machines brought the workpiece

to the welders, they would have to kneel, bend, and twist

to reach their welds.

If we did not have this machine, it would take

a whole lot longer to weld these frames.

Because how else are we really gonna be able to flip it around?

Once the welds are in place, the robots take over.

You have to have big robots to make these big machines.

The entire concept

behind robots building other things is so that

they're precise, they're accurate the entire time,

and they're very predictable.

Each frame has an individual program,

and it tells the robots what to do.

So, it follows that program, and it will come to me

if it needs help, and...

Otherwise, it pretty much knows how to do its own thing.

Here, robotic arms

manoeuvre with precision around the frame,

depositing over 17 kilometres of welding wire

along a pre-programmed welding path for each 797 truck.

So, this is actually what our welding wire looks like.

This is what we use to weld the frames together.

So, the weld wire is covered in a copper coating

to make sure that it doesn't

react to the atmosphere and that it doesn't rust.

Copper is uniquely durable.

When it's exposed to the air, it forms a distinctive green patina

that protects it from further corrosion.

So, the rollers on the back feed the wire up through this hose,

into these rollers,

that allow the robot to just feed all the time.

And it keeps a consistent speed and pace.

This automated system works continuously for 14 hours

to weld the entire frame.

It would take two skilled welders 48 hours

to do the same work.

For trucks that are used in heavy-duty mining environments,

creating a frame that has structural integrity

and durability is crucial.

Mining trucks need to be able to work 24 hours a day

in the demanding setting of a mine,

climbing and descending steep hills

with hundreds of tons of cargo.

Creating trucks this tough

requires humans and robots to work side by side.

The robots that are in their own factories,

working with other robots, they're just called robots.

But robots that are working alongside humans

and interacting with humans using sensors

are called co-bots.

Co-bots depend on human support to do their jobs.

I change the torch,

I make sure the nozzle is clean, I check the tip,

check the weld wire, and make sure that it's good to go.

I'm pretty much the robot's assistant.

played such a heavy handobos

in the manufacturing process.

The Caterpillar Tractor Company

was formed in 1925, and at that time,

workers assembled machines with hand tools.

Large components, like engine blocks and frames,

were often produced by shaping metal under high pressure

or casting molten steel with moulds.

Operators had to be strong enough to physically crank

handwheels and manipulate levers on milling,

turning and drilling machines.

- All right. -All right.

All clear!

In the 21st century, manufacturing technology

is fabricated for the future,

allowing Caterpillar to make bigger trucks than ever.

We have a system of fork trucks,

cranes, and automatically guided vehicles

that move the components around this massive campus.

We're going to need to go a little bit more.

More?

Industrial tugs effortlessly push

gigantic steel components along specialized rails

that run the entire length of the factory.

- Perfect! -All right.

This tiny thing right here pushes at least 30,000 pounds.

I'm strong, but I ain't that strong.

Automatically guided vehicles or AGVs

navigate autonomously through the factory,

delivering tools and parts to operators.

Autonomous systems are perfect for simple repetitive tasks.

The machine can follow pre-mapped routes

and programmed activities.

So, the AGV actually helps us out quite a bit.

It's able to free up more operators

to be more efficient on their jobs, not have to worry about

walking across the building to get their kits,

to walk them back, in order to get their operations

done in a timely manner.

Cranes, powerful enough to lift

an assembled 797 chassis, move components overhead.

These cranes consist of horizontal beams

spanning the width of a factory, called bridges,

with movable carriages that travel along them like trolleys.

We couldn't do anything

in this factory without these cranes.

Everything weighs too much,

they're too bulky.

Just without them, nothing would work.

The assembled and welded frame

is lifted to the inspection station.

And now, it is time to ensure the welds can hold up

to the punishment they'll be facing.

The way to do that

is to look inside the steel frame with ultrasound.

So, this is a ultrasonic couplet,

and it allows the ultrasound to go into the metal,

so that we can do our ultrasound inspection.

DR. EL-SAYEGH: The factory checks the integrity

of the welds with an industrial ultrasound

that is very similar to a medical ultrasound.

It just works at a higher frequency.

The ultrasound scanner emits sound waves

that pass through the frame.

If they encounter an internal defect,

like cracks or a gap in the weld,

part of that wave is reflected back,

showing the operator the depth and size of any defects.

Without this technology,

we wouldn't have a good view of the quality of the weld

below the surface.

Every single frame produced here

must match the engineering specifications exactly.

So, a handheld 3D scanner

is used to inspect each completed frame.

This is a MetraSCAN 3D.

It basically scans the part and makes it a 3D model.

There's cameras all around this thing,

and you can do a whole 360

or even twist your wrist and it'll still see the part.

There's nothing like this that exists.

It's the top of the line.

This machine can quickly

identify any discrepancies

between the 3D model and the original computer-aided design,

allowing for early corrections to be made.

I like seeing the 3D model,

and it's very satisfying to see it get printed on screen.

It's addicting.

The frame is painted

and the truck begins to take shape.

All right, go ahead and start up, Jeremy.

Once the steel frame is solidly locked together...

All right, that's good.

...the other components of the truck

are lifted into place with cranes.

It can be intense. It's big, it's huge,

it's intimidating, but you get used to it, so...

The mining truck's

nearly 2,000 kilogram radiator

is guided into position.

Keep going on down when you're ready. Okay.

All right, going down.

- South a little bit. - South, yep.

- All right, start down. -Going down.

We just got to watch these stabilizers here

and make sure it all lines up.

All right, isolators in.

Got it? All right.

Yeah, right in there.

Technicians systematically attach

each component that makes this machine functional -

the engine, hydraulic tank, and the transmission.

Right here, we have the transmission of the 797.

Here is the 797 engine.

Engine produces 4,000 horsepower.

This kind of power enables the truck to move

massive amounts of material very efficiently,

making it an essential piece of equipment

in industries like mining and construction,

where transporting huge quantities of material

is routine.

I love just doing this stuff, so...

It's really cool. I mean, it's, like, huge.

And plus, we're the only people in the world that do this job.

So, it can be kind of rewarding, I guess. So, yeah.

Once the truck has been tested,

it's finally ready to be sent to the mine.

This facility has got unbelievable capabilities.

We can do pretty much everything to build machines,

and we can handle it within the walls of Decatur.

This is one mighty factory.

Don't underestimate it.

These machines are sent all over the world,

ready to move the earth itself.