Fire-tube boiler facts for kids

Diagram of a fire-tube boiler

Imagine a big metal box filled with water. Inside this box, there are many tubes. A fire-tube boiler is a special kind of boiler where hot gases from a fire travel through these tubes. As the hot gases move through the tubes, their heat warms up the water around the tubes. This makes the water get super hot and turn into steam.

You'll often find fire-tube boilers in steam locomotives, which are old-fashioned trains powered by steam.

How Fire-Tube Boilers Work

A fire-tube boiler works by using hot gases to heat water. First, a fire burns in a special area called the firebox. This fire creates very hot gases. These hot gases then travel through many tubes that are surrounded by water.

As the hot gases pass through the tubes, their heat transfers through the metal walls of the tubes to the water outside. This makes the water get hotter and hotter. Eventually, the water boils and turns into steam. This steam is then used to power things like steam engines.

Where Are Fire-Tube Boilers Used?

Fire-tube boilers have been used for a long time in many different machines. Their most famous use is in steam locomotives. These powerful trains used the steam from fire-tube boilers to move their wheels.

They were also used in factories to power machinery. Some ships also used fire-tube boilers to create steam for their engines. While newer types of boilers exist today, fire-tube boilers were very important in the past.

Images for kids

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  This is a cut-open view of a fire-tube boiler from a DRB Class 50 train. Hot gases from the firebox (left) go through tubes in the middle, which are full of water. The steam collects at the top.

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  A Lancashire boiler in Germany. This is another type of fire-tube boiler.

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  A side view of a Scotch marine boiler. The arrows show how hot gases flow. The fire is on the right, and the smoke goes out on the left.

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  Horizontal return tubular boilers from a health resort in Bad Steben.

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  A Kewanee Gas-Fired Packaged Fire-Tube Boiler from 1974.

See also

In Spanish: Caldera de tubos de fuego para niños