Early Steam Engins
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EARLY STEAM ENGINES of the Industrial Revolution Presented by BOB VAN CLEEF of the North River Railway Question: What happens when you steam clean a tank car on a cold winter day, then close the dome before the car has a chance to cool down? Answer: You get a vivid demonstration of atmospheric pressure. THE BEGINNING (?) • Heron of Alexandria a Greek mathematician inventor was born in 75 AD. He is considered the greatest experimenter of antiquity almost 2000 years ahead of his time • He invented the first steam turbine, called the aeolipile. At that time it was used as a toy, possibly to make puppets dance. • Water heated in the base was heated to steam. This steam was conducted to sphere which rotated due to the exiting of the steam through nozzles. The Groundwork is Laid • The first sign of any attempt to use steam power for industrial purposes were patents taken out in 1631 by a prolific patentee David Ramsay. One in seven of 182 patents granted in England between 1561-1642 was for the raising of water. • While this was happening in England Evangelista Torricelli of Faenza (1608-1647), Blaise Pascal (1623-1662) and Otto von Guericke (1602- 1686) engaged in a series of scientific experiments which showed the effects of atmospheric pressure and that if a vacuum could be created the weight of the atmosphere could be a useful source for the transmission of power. • A further discovery relevant to the development of steam power that would be used later was Boyles Law which states the volume of a given mass of gas varies inversely with its pressure when its temperature remains constant. Dennis Papin • Papin started as an assistant of Huygens who showed him the gunpowder-engine. • In 1679 he invented "A New Digester or Engine (above), for softaing bones, the description of its makes and use in cookery, voayages at see, confectionary, making of drinks, chemistry, and dying, etc.” Note the Safety Valve. FIRST ATMOSPHERIC STEAM ENGINE • Papins’ first 1690 steam “engine” looked a lot like his pre-digester. The cylinder was filled up halfway with water then heated. • The water converts into steam and presses the piston up and the heat is removed. When the steam condenses, the atmospheric pressure will press the piston back down. • The power stroke occurs not during the vaporizing but during the condensation of steam. Other Papin Steam Engines • Papin continued to develop his ideas mostly for draining water from mines They were continued after his death in 1712 by Thomas Newcomen. • Many inventors, even in these early days fought for and were hampered by patents. Thomas Savery First Practical Steam Pump • Savery produced a practical steam pump capable of continuous operation in 1698 but with the unfortunate defect of being unsuitable for pumping water out of mines as it could only pump water to a height of twenty feet, not enough to get water out of most mines. • Furthermore the machine lacked a safety valve and was inclined to explode on occasion due to the pressure of steam on the boiler. • Nevertheless Savery's engine was the first to be sold commercially. Savery’s Engine, How It Works, Part 1 • Here, the non return valve in the delivery pipe would be held closed by the weight of water above it. The steam valve was opened to fill the vessel with steam and then closed again. • Water would be poured or sprayed on the outer surface of the vessel, which condensed the steam and caused a vacuum within. • Atmospheric pressure would then push the water up the suction pipe to fill the vessel. Savery’s Engine, How It Works, Part 2 • In this next stage the steam valve would be opened to allow steam pressure to build up in the vessel. • This would tend to close the non return valve in the suction pipe and force the water out of the vessel and up the delivery pipe. • The cycle would then be repeated. Thomas Newcomen First Practical Engine •The atmospheric engines built by Thomas Newcomen starting in 1712, are referred to as a Newcomen engines. •They were the first practical device to harness the power of steam to produce mechanical work. •His large Three story high machines also used a vacuum to move the piston in one direction but used both gravity and atmospheric pressure to push it the other way. •Note also that cold water is injected directly into the chamber to speed the condensation of steam. A TYPICAL NEWCOMEN ENGINE • Newcomen's engines began operating in mines In the years following 1712 all over England, Scotland, Wales and in Hungary, France, Belgium and possibly in Germany and Spain. • An important reason for the success of Newcomen's engine over the Savery engine was that Newcomen's was an atmospheric engine that did not need to use steam pressure any higher than that of the atmosphere. JAMES WATT Several Improvements • Watt noted In 1765, after being asked to repair a Newcomen engine, noted there was a great wastage of steam resulting from the heating of the cylinder and its cooling at each stroke. • He realized that if a separate vessel containing a vacuum was connected to the cylinder the steam would rush into the separate vessel and could be condensed without cooling the cylinder. • The separate vessel, commonly called the separate condenser, was patented in 1769 and the patent was later extended by Parliament for an extra 25 years. Steam Engine with Condenser • The partnership of Boulton and Watt was formed in 1773. • Trials were made and the new engine was found to have extra power and to use one quarter of the fuel of the Newcomen engine. • Sales were soon being made to mine owners around Great Britain and Europe. Watt Rotary Engine • The Watt engine became truly revolutionary with the addition of rotary motion which would allow it to drive all kinds of machinery. • Experiments had been made to get rotary motion out of Newcomen engines with some limited success but Watt was eventually able to create a rotary engine although it required many changes in mechanism. • Steam acted on both sides of the piston but it remained as “low pressure” engine. A Watt Machine In the early Watt engines steam was admitted throughout the whole for- stroke and energy was wasted. Watt stopped the admission of steam into the cylinder when the piston had made only part of its stroke, the rest of the stroke being performed by the steam expanding from boiler pressure to the low pressure of the condenser. This resulted in better fuel economy for the engine. Portable Winding Machines Winding engines, a smaller cousin to the larger fixed steam engines which could be moved with relative ease were also developed at this time for much smaller tasks such as pulling wagons of coal and ore up inclines too steep for horses to draw. These in time were “miniaturized” further for use in the American logging industry. RICHARD TREVITHICK • Trevithick developed the first successful high-pressure engine that ran at about 40psi while working in the coal mines. It was soon in great demand in Cornwall and South Wales for raising the ore and refuse from mines. • By 1796 he had created a miniature locomotive that worked and in 1801 a much larger locomotive (the Puffing Devil ) he used to take seven friends on a short journey. it could only go on short journeys as it was impossible to keep up steam for any length of time. First Steam Locomotive • Trevithick produced the world's first steam engine to run successfully on a plankway in 1804. The locomotive managed to haul ten tons of iron, seventy passengers and five wagons from the ironworks at speeds of nearly five miles an hour. • Trevithick's locomotive employed the very important principle of turning the exhaust steam up the chimney, so producing a draft which drew the hot gases from the fire more powerfully through the boiler thus providing more steam. • Unfortunately, like most of his ventures, it was not a commercial success. First Passenger Train Trevithick in 1808 was also the first to charge the public for rides as a novelty. He erected a circular railway in London where people paid a shilling a time to ride in a carriage pulled by his new locomotive called “Catch Me Who Can” at the breakneck speed of 12 mph. Plankway Vs. Railway • The plankways of this time were essentially wooden planks with some iron strips laid on top to protect and to prevent wear of the wood. • They were not designed to carry the weight of a 5-ton locomotive. Pig-iron flanges and ribbing was gradually introduced to help strengthen and support the rails but even that proved quite brittle and broke easily under heavy weights. • It was not until wrought iron rails became available that heavy engines became feasible. George Stephenson, a Pioneer • Stephenson first worked in various colaries starting in 1802 . • By 1814 he had constructed a locomotive (the Blutcher) that could pull thirty tons up a hill at 4 mph. • In 1815 he developed a lamp (below) that did not cause explosions in coal mines. • He had built 16 more locomotives of various designs by 1819. • In 1821-3 he was appointed engineer for the construction of the Stockton and Darlington railway. • Edward Pease, Michael Longdridge, George Stephenson and his son Robert formed a company to make the locomotives. • Later he opened his Liverpool & Manchester Railway. Robert Stephenson • Robert Stephenson, George’s son, was a prolific inventor in his own right and might have been better known had he not been overshadowed by his father.