Crane and Bricks Do You Know?

# There are lots of things All around us

# Exciting things That surround us

# But how does it work?

# Do you know?

# How is it made?

# Do you know?

# Things that go up Things that go down

# Things that go pop! Things that go round

# With special cameras To show you inside

# It's going to be a big surprise

# But how does it work?

# Do you know?

# How is it made?

# Do you know?

# Do you know?

# Let's find out! #

Hello, I'm Maddie, and today I'm on a building site.

Just think, the house or flat where you live once started off like this!

A great big pile of bricks and wood ready to be made into a building.

You should never go onto a building site without a grown-up,

but we've got special permission to show you something really exciting.

A lot of the things used to make houses are very heavy!

Far too heavy for me to pick up.

So, I need something super clever to help me.

Can you guess what it is?

A crane!

A crane is the safest way to move things around that are too heavy

for people to pick up.

But do you know how a crane works?

Let's find out.

Before the crane can do anything, it needs to stand on its own feet.

You should never play around vehicles.

Always make sure you're near a grown-up.

These special feet keep the crane steady when it picks up

heavy things, and stops it rolling away.

Look how it's lifting the wheels off the ground.

The place where the driver sits is called the cab.

In here, there are lots of levers he uses with his hands,

and pedals, which he moves with his feet.

The levers are connected to the big arm, and when the driver

moves the levers, this big arm moves across the sky.

It's called the boom, and look!

It gets longer, too!

The boom gets longer and shorter in the same way my telescope works.

The first part of my telescope is slightly thinner than

the second part.

So, this means the first part can move easily in and out.

Meaning the telescope can get longer or shorter,

just like the boom on the crane.

So, we've seen how the driver uses the levers to move the boom

around, but how does the boom get longer and shorter,

and move higher into the sky?

To find out, we need to take a closer look.

BEEP-BEEP! Here comes the crane.

And there's the boom.

To make the crane get longer and higher, there are special

tubes called hydraulic cylinders underneath the boom.

The tubes are full of water and oil.

When a button is pressed in the cab,

the water and oil are pumped upwards inside the tube.

They have nowhere to go, and so this pushes the boom up.

There are also hydraulic cylinders inside the boom.

When another button is pushed,

the water and oil inside these cylinders are pumped up too.

This pushes the boom out, making it longer.

But do you know how the crane picks things up?

Different things can be attached to the end

of the boom to pick things up in all sorts of ways.

A fork, to lift things up from the bottom.

Or a grabber to grab hold of things, like a great big hand.

Or, a chain, to pick things up from the top.

There's something on the end of this boom. Do you know what this is?

That's right, it's called a hook.

And the crane uses the hook to hook onto things to pick them up.

It's clever, isn't it?

I've got my special camera with me, and I'm going to put it on

the hook so we can see what it looks like from high up on the crane.

And we have lift-off!

The special camera is moving higher into the air.

Hello!

SHE LAUGHS

The special camera can see so much from way up high.

It's still going, higher and higher.

I can't believe it! I look as small as an ant!

That is so high!

Should we bring it back down again?

Hello, camera!

How brilliant was that?

But we want the crane to move this great big pile of wood onto

the back of that truck.

Let's see how it does it.

Up goes the boom. Listen to the sound it makes...

WHEEOO-OO

It's like an aeroplane taking off!

That's the hydraulic cylinders pushing the boom arm up

into the sky.

Once the boom is in the right position, some special chains

are wrapped around the wood, and attached to the hook.

Up we go, Paul!

The chains are on, and the boom is about to lift up that pile of wood!

It's a bit like a game of hook the duck, isn't it?

And have you played that before?

That pile of wood weighs the same as a family car, but it's

no problem for the crane, is it?

The boom is moving across in the sky to make sure the wood is in

the right position, and then it will lower it down onto the truck.

Brilliant!

What was your favourite bit about seeing how a crane works?

Can you remember the name of the big arm that the driver controls?

That's right - it's called the boom.

Did you like the sound the hydraulic cylinder made as it

pushed to boom up into the sky?

WHEEOO-OO

And did you see how high up the crane went with my special camera?

That is so high!

There are lots of things that cranes can move. There's...wood.

And these - bricks.

Most houses and buildings are made with lots of bricks.

The bricks are built into walls that hold up the roof

and keep out the rain and wind, helping us to stay warm and safe.

They have to be very strong, and last a long time.

But do you know how bricks are made?

Let's go and find out.

Well, to make a brick you have to start off in a place like this.

It's called...a quarry!

A quarry is a place where we dig in the ground for things

like rock or sand.

This digger is digging for something used to make bricks - clay.

This is clay.

It's found underground and it's full of water,

which makes it all squishy!

Just listen to the sound.

SQUELCH!

All squelchy and soft.

Clay can be squished into all sorts of shapes,

and it's used to make lots of different things. Clay makes...

dinner plates, plant pots, you might have even used clay yourself.

Look, I've turned some clay into a little man!

As well as clay, bricks are made from this - sand.

Sand is really strong and is made from rocks that are

crushed into tiny, tiny bits.

Now, if you've ever built a sandcastle, then you'll know

just how good sand is for building things.

The sand is mixed with the clay, and these tiny black things.

Do you know what this is?

It's called coal.

Coal is made from trees and plants that died millions of years ago.

And, over time, it's turned black.

And now it's more like a rock than plants.

Isn't that amazing?

Now, let's going see how the clay, the sand,

and the coal are all mixed together.

Come and look.

Wow! Oh!

The clay, sand and coal is being mixed inside this huge drum.

But I want to get a closer look.

Luckily, I've got my special camera with me, on a long pole,

so we can get right inside the mixer and see what's going on.

Wow! That's brilliant!

The two big wheels inside the drum are spinning round

to really crush up the sand, the clay and the coal.

To mix it together.

When the mix is ready,

it goes along a special moving shelf called a conveyer belt.

It travels through the factory and then it goes through this machine,

oozes onto the table, where John can turn it into a brick.

John uses a special box like this.

It's called a mould, and it's the shape of a brick.

John puts in a dollop of the mixture,

which he flattens with a piece of wood.

He then turns the mould over, and out comes a brick.

The problem is, even though the mixture looks like a brick,

it's still soft and squidgy!

And you can't build a house with a brick like that!

Do you know how we could make the brick dry and turn hard?

The bricks are put in a special place called a kiln to dry.

They will have to be in there for three whole days!

The bricks are now dry, but they're not very strong or hard.

They're still a little bit...crumbly.

To become hard enough to be built into houses,

they have to be cooked in an oven.

This is called firing, and it's really noisy!

Can you see that the bricks have turned yellow?

This means that they're very, very hot.

The bricks are fired for another three days.

Firing the bricks makes the clay dry out even more,

so they become really hard.

And these are finished bricks.

KNOCK KNOCK KNOCK!

Ho-ho-ho! Wow! I can't believe how much they've changed.

They're not soft and squishy any more.

Now, they're really, really hard!

And, I think, ready to build a house with.

KNOCK!

I loved seeing how bricks were made. Did you?

What was your favourite bit?

Can you remember the name of the special boxes the clay and

sand mixture was put into?

That's right, they're called moulds, and they give the bricks

their special shape.

Did you like the sound of the sloppy clay squelching in my hands?

SQUELCH!

And did you see how the bricks got so hot in the kiln that they

turned yellow?

So, the next time you're in your house, you'll know how

the bricks were made, and how the big cranes were used

to move them all about. See you next time.

# There are lots of things

# All around us

# Exciting things

# That surround us

# But how does it work?

# Do you know?

# How is it made?

# Do you know?

# Do you know?

# Let's find out! #