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Steam locomotive

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A steam locomotive is a machine on wheels that moves itself and other vehicles.

Steam locomotive work
Steam locomotive work

It works by using the power of expanding steam. To make this happen, the engine burns fuel like coal, oil, or sometimes wood. This heat warms up water inside a large part called a boiler.

Cutaway steam locomotive
Cutaway steam locomotive

When water gets hot enough, it turns into gas called steam. This steam takes up much more space than the liquid water did. In fact, the volume increases 1,600 to 1,700 times. This expanding steam provides the force needed to move the heavy machine.

How does this expansion turn into movement? The steam is let into cylinders at each end of the engine.

Steam locomotive running gear
Steam locomotive running gear

Inside these cylinders, the steam pushes against pistons. These pistons are mechanically connected to the locomotive's main wheels. As the steam pushes the pistons, the wheels begin to turn.

Steam locomotive gear (JŽ 06-018; Slovenia)
Steam locomotive gear (JŽ 06-018; Slovenia)

Most locomotives carry their fuel and water in a part called a tender. This tender is usually coupled right behind the engine. Some designs even use electric boilers or turbines instead of pistons.

Steam engines were first developed in the United Kingdom during the early 1800s.

Locomotive trevithick
Locomotive trevithick

Richard Trevithick built the first locomotive known to haul a load in 1804. He had previously built an engine for trials in 1802. Later, Matthew Murray built the Salamanca in 1812. This was the first commercially successful steam locomotive.

Blenkinsop's rack locomotive, 1812 (British Railway Locomotives 1803-1853)
Blenkinsop's rack locomotive, 1812 (British Railway Locomotives 1803-1853)

George Stephenson also played a huge role in this history. In 1825, his Locomotion No. 1 hauled passengers on a public railway. His son Robert built the Rocket, which won the Rainhill Trials in 1829.

Many famous locomotives were built with different goals in mind. Some were built for speed, while others were built for strength.

Number 4468 Mallard in York
Number 4468 Mallard in York

The LNER Class A4 4468 Mallard set a speed record on 3 July 1938. In the United States, engines could be much larger. The Union Pacific Big Boy 4014 is one of the largest operating locomotives today.

UP 4014 Departs Denver, CO At York Street
UP 4014 Departs Denver, CO At York Street

Other engines, like the Flying Scotsman, were the first to officially reach certain milestones. These machines changed how people and goods traveled across the world.

Steam power was the main way to move trains for a long time.

However, things began to change in the early 1900s. Railways started using electric and diesel locomotives instead of steam. By the late 1930s, most railways had switched to these new types of power. By the 1980s, most steam locomotives had been retired from regular work. You can still see them today on special heritage or tourist lines. They remind us of a very important time in history.

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🖼️ Images & Media (48)
File:Number 4468 Mallard in York.jpg
Number 4468 Mallard in York.jpg
File:Steam locomotive gear (JŽ 06-018; Slovenia).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
File:Flying Scotsman in Doncaster.JPG
Flying Scotsman in Doncaster.JPG
File:UP 4014 Departs Denver, CO At York Street.jpg
UP 4014 Departs Denver, CO At York Street.jpg
41018 Schiefe Ebene Nov 2016.webm
File:Locomotive trevithick.svg
Locomotive trevithick.svg
File:Blenkinsop's rack locomotive, 1812 (British Railway Locomotives 1803-1853).jpg
Blenkinsop's rack locomotive, 1812...
File:Locomotion No.1, Darlington.jpg
Locomotion No.1, Darlington.jpg
File:The Stourbridge Lion.JPG
The Stourbridge Lion.JPG
File:Adler Originalfoto.jpg
Adler Originalfoto.jpg
File:Cherepanov steam locomotive. drawing.jpg
Cherepanov steam locomotive. drawing.jpg
Diagram of steam locomotive components...

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