Watt, however, is credited with inventing the first practical engine. And so the history of the "modern" steam engine often begins with him. We can imagine a young Watt sitting by the fireplace in his mother's cottage and intently watching the steam rising from the boiling tea kettle, the beginning of a lifelong fascination with steam.
In , when he was twenty-eight and working as a mathematical-instrument maker at the University of Glasgow, a model of Thomas Newcomen's — steam pumping engine was brought into his shop for repairs. Watt had always been interested in mechanical and scientific instruments, particularly those which dealt with steam. The Newcomen engine must have thrilled him. Watt set up the model and watched it in operation.
He noted how the alternate heating and cooling of its cylinder wasted power. He concluded, after weeks of experimenting, that in order to make the engine practical, the cylinder had to be kept as hot as the steam which entered it. Yet in order to condense steam, there had some cooling taking place. That was a challenge the inventor faced.
Watt came up with the idea of the separate condenser. In his journal, the inventor wrote that the idea came to him on a Sunday afternoon in as he walked across the Glasgow Green. If the steam was condensed in a separate vessel from the cylinder, it would be quite possible to keep the condensing vessel cool and the cylinder hot at the same time. The next morning, Watt built a prototype and found that it worked.
He added other improvements and built his now-famous steam engine. After one or two disastrous business experiences, James Watt associated himself with Matthew Boulton, a venture capitalist, and owner of the Soho Engineering Works. The firm of Boulton and Watt became famous and Watt lived until August 19, , long enough to see his steam engine become the greatest single factor in the upcoming new industrial era.
Boulton and Watt, however, though they were pioneers, were not the only ones working on the development of the steam engine. They had rivals. But it wasn't until the 17th century that attempts were made to harness the power exhibited by Heron's aeolipile for practical purposes. The first practical steam engines were developed to solve a very specific problem: how to remove water from flooded mines. As Europeans of the 17th century 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.
In , de Ayanz registered the first patent for a machine that used steam power to propel water from mines. The Spanish inventor — who is also credited with inventing one of the world's first air conditioning systems — used his steam engine to remove water from silver mines in Guadalcanal, Seville. While the Spaniard first patented a steam-operated machine for use in mining, an Englishman is usually credited with inventing the first steam engine.
In , Thomas Savery, an engineer and inventor, patented a machine that could effectively draw water from flooded mines using steam pressure. Savery used principles set forth by Denis Papin, a French-born British physicist who invented the pressure cooker. Papin's ideas surrounding a cylinder and piston steam engine had not previously been used to build a working engine, but by , Savery had turned Papin's ideas into a useful invention. Using two steam boilers, Savery devised a nearly continuous system for pumping water from mines.
But despite the early success of Savery's system, it was soon discovered that his engine was only capable of drawing water from shallow depths, a problem that needed to be overcome if steam engines were to function in deep mines. Luckily for European mine owners, in another Englishman, Thomas Newcomen, developed a better way to pump water from mines.
His system used a redesigned steam engine that eliminated the need for accumulated steam pressure — a flaw in Savery's system that led to many an unfortunate explosion. Newcomen's "atmospheric" engine — so named because the level of steam pressure it used neared atmospheric pressure — was the first commercially successful machine that used steam to operate a water pump.
It had a power rating of 32 HP. Polzunov died three days before the machine was finished but it was put to work powering an air pump for a steel mill. It worked for three months before it was replaced with more conventional technology. Finally, it was James Watt who revolutionized the steam engine by making use of a separate condenser in the original design.
He came up with a separate condenser in The design saw itself take shape on a successful steam engine only 11 years later. The condenser allowed the cylinder and piston to remain hot, rather than being alternately heated and cooled as in the Newcomen engine, making for a big increase in its efficiency.
One issue that was solved was boring of the large diameter cylinders it required. John Wilkinson made a boring tool that was supported on both ends, rather than cantilevered, which made it possible to bore accurate cylinders that were as large as 50 in. This led to better sealing of the piston against the cylinder walls. The technology saw great progress. Watt licensed his engine based on the amount of fuel that it saved.
Further improvements included jacketing the cylinder and the development of a parallel linkage that enabled the piston to push and pull.
This would lead the way to rotary motion and the replacement of water wheels as a source of industrial power. Watt considered high-pressure steam but discounted it, believing the boilers of the day inadequate to contain such pressures. Watt also developed a method of measuring pressure vs. But who invented the high-pressure steam engine?
It was during that Richard Trevithick invented an engine with steam backed by high pressure. This was used to power a locomotive. These turned out to be more powerful compared to all the engines invented previously but failed to gain immediate acceptance. Watt himself voiced concern over the danger of high-pressure steam. Ultimately, it was the engine design presented by Oliver Evans that became a success. It used the concept of steam for powering an engine rather than condensing steam and creating a vacuum.
Evans came up with the first non-condensing and high-pressure steam engine in This engine was used for the first time to run a marble saw. The high-pressure engine was supplied by a copper shell boiler which was encased by wood and reinforced with iron rings.
In time, these steam engines were used in powerboats and railways in and , respectively.
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