116 Steam Power
25.3: Steam Power
25.3.1: Early Steam Engines
A steam engine, or a heat engine that performs mechanical work using steam, was first described in the 1st century CE. However, it was the designs of Savery’s engine in 1698 and Newcomen’s engine in 1712 that were first used commercially and inspired the further development of steam technology.
Learning Objective
List the early iterations of the steam engine
Key Points
- A steam engine is a heat engine that performs mechanical work using steam. The history of the steam engine stretches back as far as the 1st century CE. Greek mathematician Hero of Alexandria described the first recorded rudimentary steam engine, known as the aeolipile. In the following centuries, the few early steam-powered engines were, like the aeolipile, experimental devices used by inventors to demonstrate the properties of steam.
- The first commercial steam-powered device was a water pump developed in 1698 by Thomas Savery, who demonstrated it to the Royal Society a year later. The patent has no illustrations or even description, but in 1702 Savery described the machine in his book The Miner’s Friend, or, An Engine to Raise Water by Fire, in which he claimed that it could pump water out of mines.
- Savery’s engine received some use in mines and pumping stations and for supplying water wheels used to power textile machinery. An attractive feature of the Savery engine was its low cost. Bento de Moura Portugal introduced an ingenious improvement of Savery’s construction “to render it capable of working itself,” as described by John Smeaton in 1751. It continued to be manufactured until the late 18th century.
- The first commercially successful engine that it could generate power and transmit it to a machine was the atmospheric engine, invented by Thomas Newcomen around 1712. It was an improvement over Savery’s steam pump, using a piston as proposed by Papin. Newcomen replaced the receiving vessel (where the steam was condensed) with a cylinder containing a piston based on Papin’s design. Instead of the vacuum drawing in water, it drew down the piston.
- The engine was relatively inefficient and in most cases was used for pumping water. It was employed for draining mine workings at depths previously impossible and for providing a reusable water supply for driving waterwheels at factories sited away from a suitable “head.” Water that passed over the wheel was pumped back up into a storage reservoir above the wheel.
- Newcomen’s engine held its place without material change for about 75 years, spreading gradually to more areas of the UK and mainland Europe. Experience led to better construction and minor refinements in layout. Its mechanical details were much improved by John Smeaton, who built many large engines of this type in the early 1770s; his improvements were rapidly adopted. By 1775, about 600 Newcomen engines had been built.
Key Terms
- atmospheric engine
- An engine invented by Thomas Newcomen in 1712, often referred to simply as a Newcomen engine. The engine operated by condensing steam drawn into the cylinder, thereby creating a partial vacuum and allowing the atmospheric pressure to push the piston into the cylinder. It was the first practical device to harness steam to produce mechanical work.
- Steam engine
- A heat engine that performs mechanical work using steam as its working fluid.
- aeolipile
- A simple bladeless radial steam turbine, also known as a Heron’s engine, that spins when the central water container is heated. Torque is produced by steam jets exiting the turbine, much like a tip jet or rocket engine. In the 1st century CE, Hero of Alexandria described the device, and many sources give him the credit for its invention.
- beam engine
- A type of steam engine in which a pivoted overhead beam is used to apply force from a vertical piston to a vertical connecting rod. This configuration, with the engine directly driving a pump, was first used by Thomas Newcomen around 1705 to remove water from mines in Cornwall.
Introduction of the Steam Engine
A steam engine is a heat engine that performs mechanical work using steam. The history of the steam engine stretches back as far as the 1st century CE. Greek mathematician Hero of Alexandria described the first recorded rudimentary steam engine, known as the aeolipile. In the following centuries, the few early steam-powered engines were, like the aeolipile, experimental devices used by inventors to demonstrate the properties of steam. A rudimentary steam turbine device was described by Taqi al-Din in 1551 and by Giovanni Branca in 1629. Jerónimo de Ayanz y Beaumont received patents in 1606 for 50 steam-powered inventions, including a water pump for draining inundated mines. Denis Papin, a Huguenot refugee, advanced the construction of the steam digester in 1679 and first used a piston to raise weights in 1690.
Savery’s Engine
The first commercial steam-powered device was a water pump developed in 1698 by Thomas Savery, who demonstrated it to the Royal Society a year later. The patent has no illustrations or even description, but in 1702 Savery described the machine in his book The Miner’s Friend, or, An Engine to Raise Water by Fire, in which he claimed that it could pump water out of mines. Savery’s engine had no piston and no moving parts except the taps. It was operated by first raising steam in the boiler and then admitting it to one of the first working vessels, allowing it to blow out through a downpipe into the water to be raised. When the system was hot and therefore full of steam, the tap between the boiler and the working vessel was shut and, if necessary, the outside of the vessel was cooled. This made the steam inside it condense, creating a partial vacuum, and atmospheric pressure pushed water up the downpipe until the vessel was full. At this point, the tap below the vessel was closed and the tap between it and the up-pipe opened, and more steam was admitted from the boiler. As the steam pressure built up, it forced the water from the vessel up the up-pipe to the top of the mine.
Savery’s original patent of July 1698 gave 14 years’ protection. The next year, an Act of Parliament was passed, which extended his protection for a further 21 years. This Act became known as the Fire Engine Act. Savery’s patent covered all engines that raised water by fire and thus played an important role in shaping the early development of steam machinery in the British Isles.
Newcomen’s Engine
The first commercially successful engine that it could generate power and transmit it to a machine was the atmospheric engine invented by Thomas Newcomen around 1712. It was an improvement over Savery’s steam pump, using a piston as proposed by Papin. Newcomen replaced the receiving vessel (where the steam was condensed) with a cylinder containing a piston based on Papin’s design. Instead of the vacuum drawing in water, it drew down the piston. This was used to work a beam engine, in which a large wooden beam rocked upon a central fulcrum. On the other side of the beam was a chain attached to a pump at the base of the mine. As the steam cylinder was refilled with steam, readying it for the next power stroke, water was drawn into the pump cylinder and expelled into a pipe to the surface by the weight of the machinery.
Newcomen and his partner John Calley built the first successful engine of this type at the Conygree Coalworks near Dudley in the West Midlands. The engine was relatively inefficient and in most cases was used for pumping water. It was employed for draining mine workings at depths previously impossible, and also for providing a reusable water supply for driving waterwheels at factories sited away from a suitable “head.” Water that had passed over the wheel was pumped back up into a storage reservoir above the wheel.
The Newcomen engine operated by condensing steam drawn into the cylinder, thereby creating a partial vacuum and allowing the atmospheric pressure to push the piston into the cylinder. It was the first practical device to harness steam to produce mechanical work
Newcomen’s engine held its place without material change for about 75 years, spreading gradually to more areas of the UK and mainland Europe. At first brass cylinders were used, but these were expensive and limited in size. New iron casting techniques pioneered by the Coalbrookdale Company in the 1720s allowed bigger cylinders to be used, up to about 6 feet (1.8 m) in diameter by the 1760s. Experience led to better construction and minor refinements in layout. Its mechanical details were much improved by John Smeaton, who built many large engines of this type in the early 1770s, and his improvements were rapidly adopted. By 1775, about 600 Newcomen engines had been built.
Attributions
- Early Steam Engines
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“Steam power during the Industrial Revolution.” https://en.wikipedia.org/wiki/Steam_power_during_the_Industrial_Revolution. Wikipedia CC BY-SA 3.0.
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“Newcomen atmospheric engine.” https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine. Wikipedia CC BY-SA 3.0.
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“Savery-engine.jpg.” https://commons.wikimedia.org/wiki/File:Savery-engine.jpg. Wikimedia Commons Public domain.
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“800px-Newcomen6325.png.” https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine#/media/File:Newcomen6325.png. Wikipedia Public domain.