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Steam locomotive

technology Maturity 7-9

A steam train is very strong.

Steam locomotive work.gif
Steam locomotive work.gif
It uses steam to move. It burns coal to heat water. This makes the steam push. The steam makes the wheels turn.
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
It can pull many cars. Do you like trains?

46 words

A steam train is very strong.

Steam locomotive work.gif
Steam locomotive work.gif
It uses steam to move. It burns coal or oil to heat water. This makes steam. The steam grows much larger.
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
This steam pushes parts to turn the wheels. The engine can pull many cars. Some trains were very fast. One train reached a huge speed.
Number 4468 Mallard in York.jpg
Number 4468 Mallard in York.jpg
These trains used to run everywhere. Now, some still run for fun.

78 words

A steam locomotive is a machine on wheels.

Steam locomotive work.gif
Steam locomotive work.gif
It uses steam to move itself and other cars. It works by burning fuel like coal or oil. This heat warms up water in a large part called a boiler.
Cutaway steam locomotive.jpg
Cutaway steam locomotive.jpg
When water gets hot, it turns into steam. This steam takes up much more space than water. The steam pushes against pistons inside cylinders. These pistons are connected to the main wheels. This movement makes the wheels turn.
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg

Steam engines started in the United Kingdom. Richard Trevithick built an engine that pulled a load in 1804. Later, George Stephenson built Locomotion No. 1. It was the first to carry passengers on a public railway in 1825. Some locomotives were very fast. The Mallard reached a record speed in 1938. Other engines were very big. The Union Pacific Big Boy is one of the largest. Most steam engines stopped working by the 1980s. Now, some still run on special tourist lines.

170 words

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

Steam locomotive work.gif
Steam locomotive work.gif
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.jpg
Cutaway steam locomotive.jpg
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.jpg
Steam locomotive running gear.jpg
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).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
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.svg
Locomotive trevithick.svg
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. 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.jpg
Number 4468 Mallard in York.jpg
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.jpg
UP 4014 Departs Denver, CO At York Street.jpg
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.

Steam train at station.webm
Steam train at station.webm
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.

467 words

A steam locomotive is a self-propelled engine on wheels that provides force to move itself and other vehicles.

Steam locomotive work.gif
Steam locomotive work.gif
This machine uses the expansion of steam to create mechanical energy. It is a vital piece of technology that powered the industrial age. By converting thermal energy into motion, these engines revolutionized how people and goods traveled across continents. They served as the primary method of railway transport for over a century.
Cutaway steam locomotive.jpg
Cutaway steam locomotive.jpg

The mechanism of a steam locomotive relies on a specific physical process. First, the locomotive burns combustible material, such as coal, oil, or occasionally wood. This fuel heats water inside a large component called a boiler. As the water reaches its boiling point, it becomes gaseous steam. This steam expands significantly, increasing its volume by 1,600 to 1,700 times.

Diagram of steam locomotive components (March 2021 version).tif
Diagram of steam locomotive components (March 2021 version).tif
This high-pressure steam is then admitted alternately to each end of cylinders. Inside these cylinders, the steam pushes against pistons. These pistons are mechanically connected to the locomotive's main wheels through rods. This sequence converts the pressure of the steam into the rotational force needed to turn the wheels.
Steam locomotive running gear.jpg
Steam locomotive running gear.jpg

Locomotives vary in their design and specific mechanical parts. Most models carry their fuel and water supplies in a tender, which is a separate car coupled to the locomotive.

Steam locomotive gear (JŽ 06-018; Slovenia).jpg
Steam locomotive gear (JŽ 06-018; Slovenia).jpg
However, some variations exist. Some designs use electrically powered boilers to generate heat. Others replace traditional pistons with turbines to drive the wheels. Some advanced systems even generate steam externally rather than inside the locomotive itself. These variations allowed engineers to adapt steam power to different tasks and environments.

The history of the steam locomotive began in the United Kingdom during the early 19th century. Richard Trevithick was a pioneer in this field. He built a locomotive for trials at Coalbrookdale in 1802. In 1804, his locomotive at Pen-y-darren became the first known to haul a load over a distance.

Locomotive trevithick.svg
Locomotive trevithick.svg
Later, Matthew Murray built the Salamanca in 1812, which was the first commercially successful steam locomotive. George Stephenson also made massive contributions. He built Locomotion No. 1, which hauled passengers on the Stockton and Darlington Railway in 1825. His son, Robert Stephenson, built the Rocket, which won the 1829 Rainhill Trials. This success helped Robert Stephenson and Company become a leading builder for the UK, the US, and Europe.

Locomotives were often designed for specific purposes, such as extreme speed or massive strength. The LNER Class A4 4468 Mallard set an official speed record on 3 July 1938.

Number 4468 Mallard in York.jpg
Number 4468 Mallard in York.jpg
In the United States, larger loading gauges allowed for much heavier machines. The Union Pacific Big Boy 4014 is an example of a very large locomotive. It weighs 1,200,000 pounds and has a tractive effort of 135,340 pounds.
UP 4014 Departs Denver, CO At York Street.jpg
UP 4014 Departs Denver, CO At York Street.jpg
For comparison, the British Class 9F freight locomotive had a weight of 161 tons and a tractive effort of 39,600 pounds. These numbers show how different engineering goals shaped the machines.

Steam technology spread globally, though it faced unique challenges in different regions. In Russia, the first locomotive was built in 1834 by the Cherepanovs, but it was eventually replaced by horses due to a lack of coal. In Australia, the Trans-Australian Railway faced issues with magnesium chloride in the bore water. This mineralized water caused serious maintenance problems for the boilers. Because about half of a train's total load was often water, the high cost of treating this water led to the early adoption of diesel-electric locomotives.

Cherepanov steam locomotive. drawing.jpg
Cherepanov steam locomotive. drawing.jpg

The era of steam began to fade in the early 1900s. Railways gradually transitioned to electric and diesel power, with full conversion beginning in the late 1930s. By the 1980s, most steam locomotives had been retired from regular service.

Steam train at station.webm
Steam train at station.webm
Today, many of these historic engines are preserved. They continue to run on tourist and heritage lines, allowing people to experience the power of steam firsthand. They remain a significant link to the history of global transportation and engineering.

694 words
🖼️ 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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