One of the Most Important Inventions in History - the Steam Engine
by Timmy Chan (6G)
The steam engine is an invention made hundreds of years ago and was first made for pumping out water from coal mines. It can also be used to power trains, factories, ships, and even cars.
The first steam engine was made in 1698 by Thomas Savery, born at Shilstone (England). The Steam engine was first used for pumping out water from flooded mines. As Europeans of the 17th-century people switched from wood to coal as their main source of fuel, mines were deepened and, as a result, often became flooded after penetrating underground water sources. It used condensing steam to create a vacuum that raised water from below and then used steam pressure to raise it higher.
A steam engine is usually supplied by a boiler. The steam may be further heated by passing it through a superheater on its way from the boiler to the engine. A common superheater is a group of parallel pipes with their surfaces exposed to the hot gases in the boiler furnace.
Talking about steam-powered machines, I will think of steam trains first. But how do steam trains work? First, the fuels of the steam engine in the train are coal or oil, fuels are used for heating the water and making steam. The water passes to the locomotive through a device called an injector. Air flows up through the grates allowing the coal to burn hotter. Water surrounds the outside of the firebox. The heat from the burning coal turns water into steam, which rises to the top of the boiler. Steam gathers at the steam dome, the highest point in the boiler. The engineer uses the throttle to regulate the amount of steam being sent to the pistons. A throttle lever in the cab opens and closes the throttle valve in the steam dome. Steam passes to the piston valves which control the admission of steam to the cylinders. Once in the piston, the steam expands, pushing it in the opposite direction. At the end of the piston stroke, an exhaust port opens, allowing the steam to escape. Then the process is reversed and repeated in the opposite direction. Steam is admitted to either side of the piston so that it is always under power. A lever in the cab allows the engineer to control the action of the piston valves. The pistons push or pull the rods connected to the drive wheels, providing the force needed to move the locomotive.
Now, scientists have discovered a new type of steam engine that is called Modern Steam and it is used to power a train. Modern Steam is a newly developed concept that is characterised by economic efficiency and environmental friendliness: One-man operation for steam locomotives. Remote-controlled steam engines for ships. Light-oil firing with clean and spark-free combustion. High thermal efficiency of engine and boiler. The good thing about modern steam is the high thermal efficiency of the engine and boiler. The latest bearing technology reduces maintenance and protects the environment.
Why is the steam engine no longer used or not popular now? According to the designers, diesel engines could run faster and work longer than steam locomotives. They used a vast amount of energy to build up steam pressure, which had to be discarded whenever the locomotive stopped or shut down. And the other reason why the steam engine is no longer popular in the modern world is that the steam engine creates a huge amount of carbon dioxide that makes carbon dioxide pollution. People want to protect the environment so now, not many steam engines are used.
Steam engines may be useful though people stopped using them because they cause carbon dioxide pollution. The steam engine may be gone but not forgotten.
