Post by Historic Docks on Jul 14, 2008 13:15:14 GMT
en.wikipedia.org/wiki/James_Watt
James Watt (19 January 1736 – 25 August 1819[1]) was a Scottish inventor and mechanical engineer whose improvements to the steam engine were fundamental to the changes brought by the Industrial Revolution.
James Watt was born on 19 January, 1736 in Greenock, a seaport on the Firth of Clyde. His father was a shipwright, ship owner and contractor, while his mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters.
Watt attended school irregularly but instead he was mostly schooled at home by his mother. He exhibited great manual dexterity and an aptitude for mathematics, although Latin and Greek left him cold, and he absorbed the legends and lore of the Scottish people.
When he was 18, his mother died and his father's health had begun to fail. Watt travelled to London to study instrument-making for a year, then returned to Scotland – to Glasgow – intent on setting up his own instrument-making business. However, because he had not served at least seven years as an apprentice, the Glasgow Guild of Hammermen (any artisans using hammers) blocked his application, despite there being no other mathematical instrument makers in Scotland.
Watt was saved from this impasse by three professors of the University of Glasgow, who offered him the opportunity to set up a small workshop within the university. It was established in 1758 and one of the professors, the physicist and chemist Joseph Black, became Watt's friend.
In 1764, Watt married his cousin Margaret Miller, with whom he had five children, two of whom lived to adulthood. She died in childbirth in 1772. In 1777 he married again, to Ann MacGregor, daughter of a Glasgow dye-maker, who survived him. She died in 1832.
Watt had a brother by the name of John. He was shipwrecked when James was 17.
Four years after opening his shop, Watt began to experiment with steam after his friend, Professor John Robison, called his attention to it. At this point Watt had still never seen an operating steam engine, but he tried constructing a model. It failed to work satisfactorily, but he continued his experiments and began to read everything about it he could. He independently discovered the importance of latent heat in understanding the engine, which, unknown to him, Black had famously discovered some years before. He learned that the University owned a model Newcomen engine, but it was in London for repairs. Watt got the university to have it returned, and he made the repairs in 1763. It too just barely worked, and after much experimentation he showed that about 80% of the heat of the steam was consumed in heating the cylinder, because the steam in it was condensed by an injected stream of cold water. His critical insight, to cause the steam to condense in a separate chamber apart from the piston, and to maintain the temperature of the cylinder at the same temperature as the injected steam, came finally in 1765 and he soon had a working model.
Now came a long struggle to produce a full-scale engine. This required more capital, some of which came from Black. More substantial backing came from John Roebuck, the founder of the celebrated Carron Iron Works, near Falkirk, with whom he now formed a partnership. But the principal difficulty was in machining the piston and cylinder. Iron workers of the day were more like blacksmiths than machinists, so the results left much to be desired. Much capital was spent in pursuing the ground-breaking patent, which in those days required an act of parliament. Strapped for resources, Watt was forced to take up employment as a surveyor for eight years. Roebuck went bankrupt, and Matthew Boulton, who owned the Soho foundry works near Birmingham, acquired his patent rights. Watt and Boulton formed a hugely successful partnership (Boulton & Watt), which lasted for the next twenty-five years.
Watt finally had access to some of the best iron workers in the world. The difficulty of the manufacture of a large cylinder with a tightly fitting piston was solved by John Wilkinson who had developed precision boring techniques for cannon making at Bersham, near Wrexham, North Wales. Finally, in 1776, the first engines were installed and working in commercial enterprises. These first engines were used for pumps and produced only reciprocating motion. Orders began to pour in and for the next five years Watt was very busy installing more engines, mostly in Cornwall for pumping water out of mines.
Steam engine designed by Boulton & Watt. Drawing from 1784.
The field of application of the invention was greatly widened only after Boulton urged Watt to convert the reciprocating motion of the piston to produce rotational power for grinding, weaving and milling. Although a crank seemed the logical and obvious solution to the conversion Watt and Boulton were stymied by a patent for this, whose holder, James Pickard, and associates proposed to cross-license the external condensor. Watt adamantly opposed this and they circumvented the patent by their sun and planet gear in 1781.
Over the next six years, he made a number of other improvements and modifications to the steam engine. A double acting engine, in which the steam acted alternately on the two sides of the piston was one. A throttle valve to control the power of the engine, and a centrifugal governor to keep it from "running away" were very important. He described methods for working the steam expansively. A compound engine, which connected two or more engines was described. Two more patents were granted for these in 1781 and 1782. Numerous other improvements that made for easier manufacture and installation were continually implemented. One of these included the use of the steam indicator which produced an informative plot of the pressure in the cylinder against its volume, which he kept as a trade secret. Another important invention, one of which Watt was most proud of, was the Parallel motion / three-bar linkage which was especially important in double-acting engines as it produced the straight line motion required for the cylinder rod and pump, from the connected rocking beam, whose end moves in a circular arc. This was patented in 1784. These improvements taken together produced an engine which was up to five times as efficient in its use of fuel as the Newcomen engine.
Because of the danger of exploding boilers and the ongoing issues with leaks, Watt was opposed from the first to the use of high pressure steam--all of his engines used steam at very low pressure.
In 1794 the partners established Boulton and Watt to exclusively manufacture steam engines, and this became a large enterprise. By 1824 it had produced 1164 steam engines having a total nominal horsepower of about 26,000. Boulton proved to be an excellent businessman, and both men eventually made fortunes.
James Watt (19 January 1736 – 25 August 1819[1]) was a Scottish inventor and mechanical engineer whose improvements to the steam engine were fundamental to the changes brought by the Industrial Revolution.
James Watt was born on 19 January, 1736 in Greenock, a seaport on the Firth of Clyde. His father was a shipwright, ship owner and contractor, while his mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters.
Watt attended school irregularly but instead he was mostly schooled at home by his mother. He exhibited great manual dexterity and an aptitude for mathematics, although Latin and Greek left him cold, and he absorbed the legends and lore of the Scottish people.
When he was 18, his mother died and his father's health had begun to fail. Watt travelled to London to study instrument-making for a year, then returned to Scotland – to Glasgow – intent on setting up his own instrument-making business. However, because he had not served at least seven years as an apprentice, the Glasgow Guild of Hammermen (any artisans using hammers) blocked his application, despite there being no other mathematical instrument makers in Scotland.
Watt was saved from this impasse by three professors of the University of Glasgow, who offered him the opportunity to set up a small workshop within the university. It was established in 1758 and one of the professors, the physicist and chemist Joseph Black, became Watt's friend.
In 1764, Watt married his cousin Margaret Miller, with whom he had five children, two of whom lived to adulthood. She died in childbirth in 1772. In 1777 he married again, to Ann MacGregor, daughter of a Glasgow dye-maker, who survived him. She died in 1832.
Watt had a brother by the name of John. He was shipwrecked when James was 17.
Four years after opening his shop, Watt began to experiment with steam after his friend, Professor John Robison, called his attention to it. At this point Watt had still never seen an operating steam engine, but he tried constructing a model. It failed to work satisfactorily, but he continued his experiments and began to read everything about it he could. He independently discovered the importance of latent heat in understanding the engine, which, unknown to him, Black had famously discovered some years before. He learned that the University owned a model Newcomen engine, but it was in London for repairs. Watt got the university to have it returned, and he made the repairs in 1763. It too just barely worked, and after much experimentation he showed that about 80% of the heat of the steam was consumed in heating the cylinder, because the steam in it was condensed by an injected stream of cold water. His critical insight, to cause the steam to condense in a separate chamber apart from the piston, and to maintain the temperature of the cylinder at the same temperature as the injected steam, came finally in 1765 and he soon had a working model.
Now came a long struggle to produce a full-scale engine. This required more capital, some of which came from Black. More substantial backing came from John Roebuck, the founder of the celebrated Carron Iron Works, near Falkirk, with whom he now formed a partnership. But the principal difficulty was in machining the piston and cylinder. Iron workers of the day were more like blacksmiths than machinists, so the results left much to be desired. Much capital was spent in pursuing the ground-breaking patent, which in those days required an act of parliament. Strapped for resources, Watt was forced to take up employment as a surveyor for eight years. Roebuck went bankrupt, and Matthew Boulton, who owned the Soho foundry works near Birmingham, acquired his patent rights. Watt and Boulton formed a hugely successful partnership (Boulton & Watt), which lasted for the next twenty-five years.
Watt finally had access to some of the best iron workers in the world. The difficulty of the manufacture of a large cylinder with a tightly fitting piston was solved by John Wilkinson who had developed precision boring techniques for cannon making at Bersham, near Wrexham, North Wales. Finally, in 1776, the first engines were installed and working in commercial enterprises. These first engines were used for pumps and produced only reciprocating motion. Orders began to pour in and for the next five years Watt was very busy installing more engines, mostly in Cornwall for pumping water out of mines.
Steam engine designed by Boulton & Watt. Drawing from 1784.
The field of application of the invention was greatly widened only after Boulton urged Watt to convert the reciprocating motion of the piston to produce rotational power for grinding, weaving and milling. Although a crank seemed the logical and obvious solution to the conversion Watt and Boulton were stymied by a patent for this, whose holder, James Pickard, and associates proposed to cross-license the external condensor. Watt adamantly opposed this and they circumvented the patent by their sun and planet gear in 1781.
Over the next six years, he made a number of other improvements and modifications to the steam engine. A double acting engine, in which the steam acted alternately on the two sides of the piston was one. A throttle valve to control the power of the engine, and a centrifugal governor to keep it from "running away" were very important. He described methods for working the steam expansively. A compound engine, which connected two or more engines was described. Two more patents were granted for these in 1781 and 1782. Numerous other improvements that made for easier manufacture and installation were continually implemented. One of these included the use of the steam indicator which produced an informative plot of the pressure in the cylinder against its volume, which he kept as a trade secret. Another important invention, one of which Watt was most proud of, was the Parallel motion / three-bar linkage which was especially important in double-acting engines as it produced the straight line motion required for the cylinder rod and pump, from the connected rocking beam, whose end moves in a circular arc. This was patented in 1784. These improvements taken together produced an engine which was up to five times as efficient in its use of fuel as the Newcomen engine.
Because of the danger of exploding boilers and the ongoing issues with leaks, Watt was opposed from the first to the use of high pressure steam--all of his engines used steam at very low pressure.
In 1794 the partners established Boulton and Watt to exclusively manufacture steam engines, and this became a large enterprise. By 1824 it had produced 1164 steam engines having a total nominal horsepower of about 26,000. Boulton proved to be an excellent businessman, and both men eventually made fortunes.