A beam engine is a type of steam engine where a pivoted overhead beam is used to apply the 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. The efficiency of the engines was improved by engineers including James Watt, who added a separate condenser; Jonathan Hornblower and Arthur Woolf, who compounded the cylinders; and William McNaught, who devised a method of compounding an existing engine. Beam engines were first used to pump water out of mines or into canals but could be used to pump water to supplement the flow for a waterwheel powering a mill.
The rotative beam engine is a later design of beam engine where the connecting rod drives a flywheel by means of a crank (or, historically, by means of a sun and planet gear). These beam engines could be used to directly power the line-shafting in a mill. They also could be used to power steam ships.
The first beam engines were water-powered and used to pump water from mines. A preserved example may be seen at the Straitsteps Lead Mine in Wanlockhead in Scotland.
Beam engines were extensively used to power pumps on the English canal system when it was expanded by means of locks early in the Industrial Revolution, and also to drain water from mines in the same period, and as winding engines.
The first steam-related beam engine was developed by Thomas Newcomen. This was not, strictly speaking, steam powered, as the steam introduced below the piston was condensed to create a partial vacuum thus allowing atmospheric pressure to push down the piston. It was therefore called an Atmospheric Engine. The Newcomen atmospheric engine was adopted by many mines in Cornwall and elsewhere, but it was relatively inefficient and consumed a large quantity of fuel. The engine was improved by John Smeaton but James Watt resolved the main inefficiencies of the Newcomen engine in his Watt steam engine by the addition of a separate condenser, thus allowing the cylinder to remain hot. Technically this was still an atmospheric engine until (under subsequent patents) he enclosed the upper part of the cylinder, introducing steam to also push the piston down. This made it a true steam engine and arguably confirms him as the inventor of the steam engine. He also patented the centrifugal governor and the parallel motion. the latter allowed the replacement of chains round an arch head and thus allowed its use as a rotative engine.
His patents remained in place until the start of the 19th Century and some say that this held back development. However, in reality development had been ongoing by others and at the end of the patent period there was an explosion of new ideas and improvements. Watt's beam engines were used commercially in much larger numbers and many continued to run for 100 years or more.
Watt held patents on key aspects of his engine's design, but his rotative engine was equally restricted by James Pickard's patent of the simple crank. The beam engine went on to be considerably improved and enlarged in the tin- and copper-rich areas of south west England, which enabled the draining of the deep mines that existed there. Consequently, the Cornish beam engines became world-famous, as they remain among the most massive beam engines ever constructed.
Because of the number of patents on various parts of the engines and the consequences of patent infringements, examples exist of Beam Engines with no makers name on any of the parts (Hollycombe Steam Collection).
In a rotative beam engine, the piston is mounted vertically, and the piston rod drives the beam as before. A connecting rod from the other end of the beam, rather than driving a pump rod, now drives a flywheel.
Early Watt engines used Watt's patent sun and planet gear, rather than a simple crank, as use of the latter was protected by a patent owned by James Pickard. Once the patent had expired, the simple crank was employed universally. Once rotary motion had been achieved a drive belt could be attached beside the flywheel. This transmitted the power to other drive shafts and from these other belts could then be attached to power a variety of static machinery e.g. threshing, grinding or milling machines.
The first steam-powered ships used variants of the rotative beam engine. These marine steam engines – known as side-lever, grasshopper, crosshead, or 'walking beam', among others – all varied from the original land-based machines by locating the beam or beams in different positions to take up less room on board ship.
Compounding involves two or more cylinders; low-pressure steam from the first, high-pressure, cylinder is passed to the second cylinder where it expands further and provides more drive. This is the compound effect; the waste steam from this can produce further work if it is then passed into a condenser in the normal way. The first experiment with compounding was conducted by Jonathan Hornblower, who took out a patent in 1781. His first engine was installed at Tincroft Mine, Cornwall. It had two cylinders – one 21-inch (0.53 m) diameter with 6-foot (1.8 m) stroke and one 27-inch (0.69 m) diameter with 8-foot (2.4 m) stroke – placed alongside each other at one end of the beam. The early engines showed little performance gain: the steam pressure was too low, interconnecting pipes were of small diameter and the condenser ineffective.
At this time the laws of thermodynamics were not adequately understood, particularly the concept of absolute zero. Engineers such as Arthur Woolf were trying to tackle an engineering problem with an imperfect understanding of the physics. In particular, their valve gear was cutting-in at the wrong position in the stroke, not allowing for expansive working in the cylinder. Successful Woolf compound engines were produced in 1814, for the Wheal Abraham copper mine and the Wheal Vor tin mine.
William McNaught patented a compound beam engine in 1845. On a beam engine of the standard Boulton & Watt design he placed a high-pressure cylinder, on the opposite side of the beam to the existing single cylinder, where the water pump was normally fitted. This had two important effects: it massively reduced the pressure on the beam, and the connecting steam pipe, being long, acted as an expansive receiver – the element missing in the Woolf design. 60 pounds per square inch (410 kPa), but showed at over 100 psi (690 kPa).[ citation needed ]This modification could be made retrospectively, and engines so modified were said to be "McNaughted". The advantages of a compound engine were not significant at pressures under
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James Watt was a Scottish inventor, mechanical engineer, and chemist who improved on Thomas Newcomen's 1712 Newcomen steam engine with his Watt steam engine in 1776, which was fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world.
A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be transformed, by a connecting rod and crank, into rotational force for work. The term "steam engine" is generally applied only to reciprocating engines as just described, not to the steam turbine. Steam engines are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term steam engine can refer to either complete steam plants, such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine.
Thomas Newcomen was an English inventor who created the atmospheric engine, the first practical fuel-burning engine in 1712. He was an ironmonger by trade and a Baptist lay preacher by calling.
Thomas Savery was an English inventor and engineer, born at Shilstone, a manor house near Modbury, Devon, England. He invented the first commercially used steam-powered device, a steam pump which is often referred to as an "engine", although it is not technically an engine. Savery's steam pump was a revolutionary method of pumping water, which solved the problem of mine drainage and made widespread public water supply practicable.
The atmospheric engine was invented by Thomas Newcomen in 1712, and is often referred to simply as a Newcomen engine. The engine was operated by condensing steam drawn into the cylinder, thereby creating a partial vacuum which allowed the atmospheric pressure to push the piston into the cylinder. It was the first practical device to harness steam to produce mechanical work. Newcomen engines were used throughout Britain and Europe, principally to pump water out of mines. Hundreds were constructed throughout the 18th century.
The Watt steam engine, alternatively known as the Boulton and Watt steam engine, was an early steam engine and was one of the driving forces of the Industrial Revolution. James Watt developed the design sporadically from 1763 to 1775 with support from Matthew Boulton. Watt's design saved so much more fuel compared with earlier designs that they were licensed based on the amount of fuel they would save. Watt never ceased developing the steam engine, introducing double-acting designs and various systems for deriving rotary power. Watt's design became synonymous with steam engines, and it was many years before significantly new designs began to replace the basic Watt design.
Richard Trevithick was a British inventor and mining engineer. The son of a mining captain, and born in the mining heartland of Cornwall, Trevithick was immersed in mining and engineering from an early age. He was an early pioneer of steam-powered road and rail transport, and his most significant contributions were the development of the first high-pressure steam engine and the first working railway steam locomotive. The world's first locomotive-hauled railway journey took place on 21 February 1804, when Trevithick's unnamed steam locomotive hauled a train along the tramway of the Penydarren Ironworks, in Merthyr Tydfil, Wales.
Stationary steam engines are fixed steam engines used for pumping or driving mills and factories, and for power generation. They are distinct from locomotive engines used on railways, traction engines for heavy steam haulage on roads, steam cars, agricultural engines used for ploughing or threshing, marine engines, and the steam turbines used as the mechanism of power generation for most nuclear power plants.
Steam power developed slowly over a period of several hundred years, progressing through expensive and fairly limited devices in the early 17th century, to useful pumps for mining in 1700, and then to Watt's improved steam engine designs in the late 18th century. It is these later designs, introduced just when the need for practical power was growing due to the Industrial Revolution, that truly made steam power commonplace.
A compound steam engine unit is a type of steam engine where steam is expanded in two or more stages. A typical arrangement for a compound engine is that the steam is first expanded in a high-pressure (HP) cylinder, then having given up heat and losing pressure, it exhausts directly into one or more larger-volume low-pressure (LP) cylinders. Multiple-expansion engines employ additional cylinders, of progressively lower pressure, to extract further energy from the steam.
Improvements to the steam engine were some of the most important technologies of the Industrial Revolution, although steam did not replace water power in importance in Britain until after the Industrial Revolution. From Englishman Thomas Newcomen's atmospheric engine, of 1712, through major developments by Scottish inventor and mechanical engineer James Watt, the steam engine began to be used in many industrial settings, not just in mining, where the first engines had been used to pump water from deep workings. Early mills had run successfully with water power, but by using a steam engine a factory could be located anywhere, not just close to a water source. Water power varied with the seasons and was not always available.
Jonathan Hornblower was a British pioneer of steam power.
A Cornish engine is a type of steam engine developed in Cornwall, England, mainly for pumping water from a mine. It is a form of beam engine that uses steam at a higher pressure than the earlier engines designed by James Watt. The engines were also used for powering man engines to assist the underground miners' journeys to and from their working levels, for winching materials into and out of the mine, and for powering on-site ore stamping machinery.
Arthur Woolf was a Cornish engineer, most famous for inventing a high-pressure compound steam engine. As such he made an outstanding contribution to the development and perfection of the Cornish engine.
The first recorded rudimentary steam engine was the aeolipile described by Heron of Alexandria in 1st-century Roman Egypt. Several steam-powered devices were later experimented with or proposed, such as Taqi al-Din's steam jack, a steam turbine in 16th-century Ottoman Egypt, and Thomas Savery's steam pump in 17th-century England. In 1712, Thomas Newcomen's atmospheric engine became the first commercially successful engine using the principle of the piston and cylinder, which was the fundamental type of steam engine used until the early 20th century. The steam engine was used to pump water out of coal mines.
Old Bess is an early beam engine built by the partnership of Boulton and Watt. The engine was constructed in 1777 and worked until 1848.
A cataract was a speed governing device used for early single-acting beam engines, particularly atmospheric engines and Cornish engines. It was a kind of water clock.
Resolution was an early beam engine, installed between 1781–1782 at Coalbrookdale as a water-returning engine to power the blast furnaces and ironworks there. It was one of the last water-returning engines to be constructed, before the rotative beam engine made this type of engine obsolete.
The Newcomen Memorial Engine is a preserved beam engine in Dartmouth, Devon. It was preserved as a memorial to Thomas Newcomen, inventor of the beam engine, who was born in Dartmouth.
Valve gear opens and closes valves in the correct order. In rotating engines valve timings can be driven by eccentrics or cranks, but in non-rotative beam engines these options are not available. In the Cornish engine valves are driven either manually or through ‘plug rods’ and tappets driven from the beam. This permits the insertions of delays at various points in the cycle, allowing a Cornish Engine to vary from one stroke in ten minutes, to ten or more strokes in one minute, but also leads to some less familiar components when compared with rotative engines.
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