Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is carbon with variable amounts of other elements. Coal is formed if dead plant matter decays into peat and over millions of years the heat and pressure of deep burial converts the peat into coal. Vast deposits of coal originates in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous and Permian times; as a fossil fuel burned for heat, coal supplies about a quarter of the world's primary energy and two-fifths of its electricity. Some iron and steel making and other industrial processes burn coal; the extraction and use of coal causes much illness. Coal damages the environment, including by climate change as it is the largest anthropogenic source of carbon dioxide, 14 Gt in 2016, 40% of the total fossil fuel emissions; as part of the worldwide energy transition many countries use less coal. The largest consumer and importer of coal is China.
China mines account for half the world's coal, followed by India with about a tenth. Australia accounts for about a third of world coal exports followed by Russia; the word took the form col in Old English, from Proto-Germanic *kula, which in turn is hypothesized to come from the Proto-Indo-European root *gu-lo- "live coal". Germanic cognates include the Old Frisian kole, Middle Dutch cole, Dutch kool, Old High German chol, German Kohle and Old Norse kol, the Irish word gual is a cognate via the Indo-European root. Coal is composed of macerals and water. Fossils and amber may be found in coal. At various times in the geologic past, the Earth had dense forests in low-lying wetland areas. Due to natural processes such as flooding, these forests were buried underneath soil; as more and more soil deposited over them, they were compressed. The temperature rose as they sank deeper and deeper; as the process continued the plant matter was protected from biodegradation and oxidation by mud or acidic water.
This trapped the carbon in immense peat bogs that were covered and buried by sediments. Under high pressure and high temperature, dead vegetation was converted to coal; the conversion of dead vegetation into coal is called coalification. Coalification starts with dead plant matter decaying into peat. Over millions of years the heat and pressure of deep burial causes the loss of water and carbon dioxide and an increase in the proportion of carbon, thus first lignite sub-bituminous coal, bituminous coal, lastly anthracite may be formed. The wide, shallow seas of the Carboniferous Period provided ideal conditions for coal formation, although coal is known from most geological periods; the exception is the coal gap in the Permian -- Triassic extinction event. Coal is known from Precambrian strata, which predate land plants—this coal is presumed to have originated from residues of algae. Sometimes coal seams are interbedded with other sediments in a cyclothem; as geological processes apply pressure to dead biotic material over time, under suitable conditions, its metamorphic grade or rank increases successively into: Peat, a precursor of coal Lignite, or brown coal, the lowest rank of coal, most harmful to health, used exclusively as fuel for electric power generation Jet, a compact form of lignite, sometimes polished.
Bituminous coal, a dense sedimentary rock black, but sometimes dark brown with well-defined bands of bright and dull material It is used as fuel in steam-electric power generation and to make coke. Anthracite, the highest rank of coal is a harder, glossy black coal used for residential and commercial space heating. Graphite is difficult to ignite and not used as fuel. Cannel coal is a variety of fine-grained, high-rank coal with significant hydrogen content, which consists of liptinite. There are several international standards for coal; the classification of coal is based on the content of volatiles. However the most important distinction is between thermal coal, burnt to generate electricity via steam. Hilt's law is a geological observation, the higher its rank, it applies if the thermal gradient is vertical. The earliest recognized use is from the Shenyang area of China where by 4000 BC Neolithic inhabitants had begun carving ornaments from black lignite. Coal from the Fushun mine in northeastern China was used to smelt copper as early as 1000 BC.
Marco Polo, the Italian who traveled to China in the 13th century, described coal as "black stones... which burn like logs", said coal was so plentiful, people could take three hot baths a week. In Europe, the earliest reference to the use of coal as fuel is from the geological treatise On stones by the Greek scientist Theophrastus: Among the materials that are dug because they are useful, those known as anthrakes are made of earth, once set on fire, they burn like charcoa
Midland Railway 115 Class
The Midland Railway 115 Class is a class of 4-2-2 steam locomotive, nicknamed "Spinners". They were designed by Samuel W. Johnson and a total of 15 of the class were built between 1896 and 1899; the fifteen locomotives in the class were built both at Derby Works. It was quite common for this class of engine to pull a typical Midland express weighing 200 and 250 long tons which suited the Class 115 perfectly. Given a dry rail they could maintain a tight schedule with 350 long tons. Speeds up to 90 mph were not uncommon and the sight of their whirring huge driving wheels earned them the nickname "Spinners". Thanks to the Midland's practice of building low powered locomotives and relying on double-heading to cope with heavier trains many enjoyed working lives of up to 30 years, they made ideal pilot engines for the Johnson/Deeley 4-4-0 classes. In the Midland Railway 1907 renumbering scheme, they were assigned numbers 670–684. During World War I most were placed in store but pressed into service afterwards as pilots on the Nottingham to London coal trains.
Twelve locomotives survived to the 1923 grouping, keeping their Midland Railway numbers in London and Scottish Railway service. By 1927 only three of the class remained, with the last engine, 673 being withdrawn in 1928 and preserved. No. 673 is the sole survivor of its class. It was steamed around 1976–1980 when it took part in the Rainhill Trials 150th cavalcade but is a static exhibit in the National Railway Museum in York. Baxter, Bertram. Baxter, David, ed. British Locomotive Catalogue 1825–1923. Volume 3A: Midland Railway and its constituent companies. Ashbourne, Derbyshire: Moorland Publishing Company. ISBN 9780903485524. Classic British steam Locomotives Casserley, H. C.. Locomotives at the Grouping 3: London and Scottish. Shepperton, Surrey: Ian Allan. ISBN 0-7110-0554-0. Essery, R. J & Jenkinson, D.. An Illustrated Review of Midland Locomotives, Volume 2: Passenger tender classes. Didcot: Wild Swan Publications. ISBN 0 906867 59 2
Matthew Kirtley was born at Tanfield, Durham. He was an important early locomotive engineer. At the age of thirteen he began work on the Darlington Railway, he became a driver on the London and Birmingham Railway. He is believed to have driven the first L&BR train to enter London. In 1839 he was appointed, first a locomotive foreman, in 1841, Locomotive Superintendent of the Birmingham and Derby Junction Railway; when that railway became one of the constituents of the Midland Railway, he became the Midland's Locomotive Superintendent. He was there Chief Mechanical Engineer from 1844 until he died in 1873. Hundreds of locomotives to his design existed, many of which were to last into the days of the London and Scottish Railway, some fifty years later. Matthew Kirtley's brother Thomas Kirtley was a locomotive engineer as was his nephew, William Kirtley, who served as locomotive superintendent on the London and Dover Railway, 1874-1898; the Midland Railway Trust’s collection of locomotives and wagon is housed in what is now named the Matthew Kirtley Building.
Walschaerts valve gear
The Walschaerts valve gear is a type of valve gear invented by Belgian railway mechanical engineer Egide Walschaerts in 1844 used to regulate the flow of steam to the pistons in steam engines. The gear is sometimes named without the final "s", since it was incorrectly patented under that name, it was extensively used in steam locomotives from the late 19th century until the end of the steam era. The Walschaerts valve gear was slow to gain popularity; the Stephenson valve gear remained the most used valve gear on 19th-century locomotives. However, the Walschaerts valve gear had the advantage that it could be mounted on the outside of the locomotives, leaving the space between the frames clear; the first locomotive fitted with the Walschaerts valve gear was built at the Belgian Tubize workshops, was awarded a gold medal at the 1873 Universal Exhibition in Vienna. In 1874 New Zealand Railways ordered two NZR B class locomotives, they were Double Fairlie locomotives, supplied by Avonside. They were Cape gauge.
The Mason Bogie, a modified Fairlie locomotive of 1874, was the first to use the Walschaerts gear in North America. The first application in Britain was on a Single Fairlie 0-4-4T, exhibited in Paris in 1878 and purchased by the Swindon and Andover Railway in March 1882. According to Ahrons, the locomotive saw little service as nobody seems to have known how to set the valves and this led to enormous coal consumption. In the 20th century, the Walschaerts valve gear was the most used type on larger locomotives. In Europe, its use was universal, whilst in North America, the Walschaerts gear outnumbered its closest competitor, the derived Baker valve gear, by a wide margin. In Germany and some neighbouring countries, like Poland and Czechoslovakia, the Walschaerts gear is named the Heusinger valve gear after Edmund Heusinger von Waldegg, who invented the mechanism independently in 1849. Heusinger's gear was closer to the form adopted, but most authorities accept Walschaerts' invention as sufficiently close to the final form.
The Walschaerts valve gear is an improvement on the earlier Stephenson valve gear in that it enables the driver to operate the steam engine in a continuous range of settings from maximum economy to maximum power. At any setting, the valve gear satisfies the following two conditions: The valve opens to admit steam to the cylinder just before the start of a piston stroke; the pressure of this steam provides the driving force. Soon before the space on one side of the piston starts to contract, the valve starts to release steam from that space to the atmosphere, so as not to impede the movement of the piston. In an economical setting, steam is admitted to the expanding space for only part of the stroke. Since the exhaust is shut, during the rest of the stroke the steam that has entered the cylinder expands in isolation, so its pressure decreases. Thus, the most energy available from the steam is used; the Walschaerts valve gear enables the engineer to change the cutoff point without changing the points at which intake starts.
Economy requires that the throttle be wide open and that the boiler pressure is at the maximum safe level to maximise thermal efficiency. For economy, a steam engine is used of a size such that the most economical settings yield the right amount of power most of the time, such as when a train is running at steady speed on level track; when greater power is necessary, e.g. when gaining speed when pulling out of a station and when ascending a gradient, the Walschaerts valve gear enables the engineer to set the cutoff point near the end of the stroke, so that the full pressure of the boiler is exerted on the piston for the entire stroke. With such a setting, when the exhaust opens, the steam in the cylinder is near full boiler pressure; the pressure in the steam at that moment serves no useful purpose. This sudden pulse of pressure causes the loud “choo” sound that members of the public associate with steam engines, because they encounter engines at stations, where efficiency is sacrificed as trains pull away.
A steam engine well adjusted for efficiency makes a soft “hhHHhh” sound that lasts throughout the exhaust stroke, with the sounds from the two cylinders overlapping to produce a nearly constant sound. The valve gear operation combines two motions; the secondary is the directional/amplitude motion, imparted at the top. Consider that the driver has adjusted the reversing lever such that the die block is at mid-gear. In this position the secondary motion is eliminated and the piston valve travel is shortest, giving minimal injection and exhaust of steam; the travel of the piston valve is twice the total of lap plus lead. Contrast this to when the die block is at the bottom of the expansion link, giving maximum steam injection and exhaust; this is used in accelerating forward from rest. Conversely when the die block is at the top of the expansion link, maximal power in reverse is obtained. Once the locomotive has accelerated the driver can adjust the reverser toward the mid-gear position, decreasing cut-off to give a more economical use of steam.
The engine's tractive e
A locomotive or engine is a rail transport vehicle that provides the motive power for a train. If a locomotive is capable of carrying a payload, it is rather referred to as multiple units, motor coaches, railcars or power cars. Traditionally, locomotives pulled trains from the front. However, push-pull operation has become common, where the train may have a locomotive at the front, at the rear, or at each end; the word locomotive originates from the Latin loco – "from a place", ablative of locus "place", the Medieval Latin motivus, "causing motion", is a shortened form of the term locomotive engine, first used in 1814 to distinguish between self-propelled and stationary steam engines. Prior to locomotives, the motive force for railways had been generated by various lower-technology methods such as human power, horse power, gravity or stationary engines that drove cable systems. Few such systems are still in existence today. Locomotives may generate their power from fuel, or they may take power from an outside source of electricity.
It is common to classify locomotives by their source of energy. The common ones include: A steam locomotive is a locomotive whose primary power source is a steam engine; the most common form of steam locomotive contains a boiler to generate the steam used by the engine. The water in the boiler is heated by burning combustible material – coal, wood, or oil – to produce steam; the steam moves reciprocating pistons which are connected to the locomotive's main wheels, known as the "drivers". Both fuel and water supplies are carried with the locomotive, either on the locomotive itself or in wagons called "tenders" pulled behind; the first full-scale working railway steam locomotive was built by Richard Trevithick in 1802. It was constructed for the Coalbrookdale ironworks in Shropshire in the United Kingdom though no record of it working there has survived. On 21 February 1804, the first recorded steam-hauled railway journey took place as another of Trevithick's locomotives hauled a train from the Pen-y-darren ironworks, in Merthyr Tydfil, to Abercynon in South Wales.
Accompanied by Andrew Vivian, it ran with mixed success. The design incorporated a number of important innovations including the use of high-pressure steam which reduced the weight of the engine and increased its efficiency. In 1812, Matthew Murray's twin-cylinder rack locomotive Salamanca first ran on the edge-railed rack-and-pinion Middleton Railway. Another well-known early locomotive was Puffing Billy, built 1813–14 by engineer William Hedley for the Wylam Colliery near Newcastle upon Tyne; this locomotive is the oldest preserved, is on static display in the Science Museum, London. George Stephenson built Locomotion No. 1 for the Stockton and Darlington Railway in the north-east of England, the first public steam railway in the world. In 1829, his son Robert built The Rocket in Newcastle-upon-Tyne. Rocket was entered into, won, the Rainhill Trials; this success led to the company emerging as the pre-eminent early builder of steam locomotives used on railways in the UK, US and much of Europe.
The Liverpool and Manchester Railway, built by Stephenson, opened a year making exclusive use of steam power for passenger and goods trains. The steam locomotive remained by far the most common type of locomotive until after World War II. Steam locomotives are less efficient than modern diesel and electric locomotives, a larger workforce is required to operate and service them. British Rail figures showed that the cost of crewing and fuelling a steam locomotive was about two and a half times larger than the cost of supporting an equivalent diesel locomotive, the daily mileage they could run was lower. Between about 1950 and 1970, the majority of steam locomotives were retired from commercial service and replaced with electric and diesel-electric locomotives. While North America transitioned from steam during the 1950s, continental Europe by the 1970s, in other parts of the world, the transition happened later. Steam was a familiar technology that used widely-available fuels and in low-wage economies did not suffer as wide a cost disparity.
It continued to be used in many countries until the end of the 20th century. By the end of the 20th century the only steam power remaining in regular use around the world was on heritage railways. Internal combustion locomotives use an internal combustion engine, connected to the driving wheels by a transmission, they keep the engine running at a near-constant speed whether the locomotive is stationary or moving. Kerosene locomotives use kerosene as the fuel, they were the world's first oil locomotives, preceding diesel and other oil locomotives by some years. The first known kerosene locomotive was a draisine built by Daimler in 1887. A kerosene locomotive was built in 1894 by the Priestman Brothers of Kingston upon Hull for use on Hull docks; this locomotive was built using a 12 hp double-acting marine type engine, running at 300 rpm, mounted on a 4-wheel wagon chassis. It was only able to haul one loaded wagon at a time, due to its low power output, was not a great success; the first successful kerosene locomotive was "Lachesis" built by Richard Hornsby & Sons Ltd. and delivered to Woolwich Arsenal railway in 1896.
The company built a series of kerosene locomotives between 1896 and 1903, for use by the British military. Petrol locomotives use petrol as their fuel. Most petrol locomotives built were petrol-mechanical, using a mechanical transmission to deliver the power output of the engine t
The cylinder is the power-producing element of the steam engine powering a steam locomotive. The cylinder is made pressure-tight with a piston. Cylinders were cast in cast iron and in steel; the cylinder casting includes other features such as mounting feet. The last big American locomotives incorporated the cylinders as part of huge one-piece steel castings that were the main frame of the locomotive. Renewable wearing surfaces were provided by cast-iron bushings; the way the valve controlled the steam entering and leaving the cylinder was known as steam distribution and shown by the shape of the indicator diagram. What happened to the steam inside the cylinder was assessed separately from what happened in the boiler and how much friction the moving machinery had to cope with; this assessment was known as "engine performance" or "cylinder performance". The cylinder performance, together with the boiler and machinery performance, established the efficiency of the complete locomotive; the pressure of the steam in the cylinder was measured as the piston moved and the power moving the piston was calculated and known as cylinder power.
The forces produced in the cylinder moved the train but were damaging to the structure which held the cylinders in place. Bolted joints came loose, cylinder castings and frames cracked and reduced the availability of the locomotive. Cylinders may be arranged in several different ways. On early locomotives, such as Puffing Billy, the cylinders were set vertically and the motion was transmitted through beams, as in a beam engine; the next stage, for example Stephenson's Rocket, was to drive the wheels directly from steeply inclined cylinders placed at the back of the locomotive. Direct drive became the standard arrangement, but the cylinders were moved to the front and placed either horizontal or nearly horizontal; the front-mounted cylinders could be placed either outside. Examples: Inside cylinders, Planet locomotive Outside cylinders, GNR Stirling 4-2-2In the 19th and early 20th centuries, inside cylinders were used in the UK, but outside cylinders were more common in Continental Europe and the United States.
The reason for this difference is unclear. From about 1920, outside cylinders became more common in the UK but many inside-cylinder engines continued to be built. Inside cylinders give a more stable ride with less yaw or "nosing" but access for maintenance is more difficult; some designers used inside cylinders for aesthetic reasons. The demand for more power led to the development of engines with four cylinders. Examples: Three cylinders, SR Class V, LNER Class A4, Merchant Navy class Four Cylinders, LMS Princess Royal Class, LMS Coronation Class, GWR Castle Class On a two-cylinder engine the cranks, whether inside or outside, are set at 90 degrees; as the cylinders are double-acting this gives four impulses per revolution and ensures that there are no dead centres. On a three-cylinder engine, two arrangements are possible: cranks set to give six spaced impulses per revolution – the usual arrangement. If the three cylinder axes are parallel, the cranks will be 120 degrees apart, but if the centre cylinder does not drive the leading driving axle, it will be inclined, the inside crank will be correspondingly shifted from 120 degrees.
For a given tractive effort and adhesion factor, a three-cylinder locomotive of this design will be less prone to wheelslip when starting than a 2-cylinder locomotive. Outside cranks set at 90 degrees, inside crank set at 135 degrees, giving six unequally spaced impulses per revolution; this arrangement was sometimes used on three-cylinder compound locomotives which used the outside cylinders for starting. This will give evenly spaced exhausts. Two arrangements are possible on a four-cylinder engine: all four cranks set at 90 degrees. With this arrangement the cylinders act in pairs, so there are four impulses per revolution, as with a two-cylinder engine. Most four-cylinder engines are of this type, it is cheaper and simpler to use only one set of valve gear on each side of the locomotive and to operate the second cylinder on that side by means of a rocking shaft from the first cylinder's valve spindle since the required valve events at the second cylinder are a mirror image of the first cylinder.
Pairs of cranks set at 90 degrees with the inside pair set at 45 degrees to the outside pair. This gives eight impulses per revolution, it increases weight and complexity, by requiring four sets of valve gear, but gives smoother torque and reduces the risk of slipping. This was unusual in British practice but was used on the SR Lord Nelson class; such locomotives are distinguished by their exhaust beats, which occur at twice the frequency of a normal 2- or 4-cylinder engine. The valve chests or steam chests which contain the slide valves or piston valves may be located in various positions. If the cylinders are small, the valve chests may be located between the cylinders. For larger cylinders the valve chests are on top of the cylinders but, in early locomotives, they were sometimes underneath the cylinders; the valve chests are on top of the cylinders but, in older locomotives, the valve chests were sometimes located alongside the cylinders and inserted through slots in the frames. This meant that, while the cylinders were outside, the valves were inside a
Under the Whyte notation for the classification of steam locomotives, 0-4-0 represents one of the simplest possible types, that with two axles and four coupled wheels, all of which are driven. The wheels on the earliest four-coupled locomotives were connected by a single gear wheel, but from 1825 the wheels were connected with coupling rods to form a single driven set; the notation 0-4-0T indicates a tank locomotive of this wheel arrangement on which its water and fuel is carried on board the engine itself, rather than in an attached tender. In Britain, the Whyte notation of wheel arrangement was often used for the classification of electric and diesel-electric locomotives with side-rod-coupled driving wheels. Under the UIC classification used in Europe and, in more recent years, in simplified form in the United States, an 0-4-0 is classified as B if the axles are connected by side rods or gearing and 020, independent of axle motoring; the UIC's Bo classification for electric and diesel-electric locomotives indicates that the axles are independently motored, which would be 0-2-2-0 under the Whyte notation.
The term Four-coupled is used for 0-4-0 locomotives. Four-wheeled is sometimes used, but this term can encompass other wheel arrangements, for example Stephenson's Rocket, an 0-2-2 four-wheeled locomotive.0-4-0 locomotives were built as tank locomotives as well as tender locomotives. The former were more common in Europe and the latter in the United States, except in the tightest of situations such as that of a shop switcher, where overall length was a concern; the earliest 0-4-0 locomotives appeared as early as c. 1802. The 0-4-0 tank engines were introduced in the early 1850s; the type was found to be so useful in many locations that they continued to be built for more than a century and existed until the end of the steam era. Richard Trevithick's Coalbrookedale, Pen-y-Darren and Newcastle locomotives were of the 0-4-0 type, although in their cases the wheels were connected by a single gear wheel; the first 0-4-0 to use coupling rods was Locomotion No. 1, built by Robert Stephenson and Company for the Stockton and Darlington Railway in 1825.
Stephenson built the Lancashire Witch in 1828, Timothy Hackworth built Sans Pareil which ran at the Rainhill Trials in 1829. The latter two locomotives worked on the Bolton and Leigh Railway. A four-wheeled configuration, where all the wheels are driving wheels, uses all the locomotive's mass for traction but is inherently unstable at speed; the type was therefore used for switchers and shunters. Because of the lack of stability, tender engines of this type were only built for a few decades in the United Kingdom, they were built for a longer period in the United States. The possible tractive effort of an 0-4-0 within normal axle load limits was not enough to move large loads. By 1900, they had therefore been superseded for most purposes by locomotives with more complex wheel arrangements, they continued to be used in situations where tighter radius curves existed or the shorter length was an advantage. Thus, they were employed in dockyard work, industrial tramways, or as shop switchers; the wheel arrangement was used on specialised types such as fireless locomotives, crane tanks, tram engines and geared steam locomotives.
It was widely used on narrow gauge railways. In New South Wales, Dorrigo Steam Railway and Museum has preserved twelve 0-4-0 steam locomotives and eight 0-4-0 diesel locomotives, a total of twenty examples, all on the one site; the Catumbela Sugar Estate in Angola operated a narrow gauge line on the estate. One of their 0-4-0 locomotives, Rührthaler Maschinen-Fabrik 963 of 1929, was rebuilt with a diesel engine. Finland had the Vk4 classes with an 0-4-0 wheel arrangement; the E1 was a class of only two locomotives, numbered 76 and 77. The Vk4 was a class of only two locomotives, built by Borsig Lokomotiv Werke of Germany in 1910; the Vk4s were used at a fortress, were also used in dismantling the fortress, after which one locomotive went into industrial use and was scrapped in 1951. The other was sold to nicknamed Leena, it became No. 68 and is now the oldest working broad gauge locomotive in Finland, being preserved at the Finnish Railway Museum. The Semarang-Cheribon Stoomtram Maatschappij imported 27 standard gauge 0-4-0T locomotives of the B52 class between 1908 and 1911 to operate services from Kalibrodi-Semarang to Tanggung and Yogyakarta.
They were built by Sächsische Maschinenfabrik in Germany. They were a modern locomotive design for the time, equipped with a superheater; the largest allocation of B52 class locomotives was in Tegal, Central Java for services to Purwokerto. Some were converted to tram engines and worked in Tegal and Purwokerto. All 27 locomotives were in existence at the end of 1960. Two locomotives have been preserved, B5212 at the Taman Mini Indonesia Indah Museum of Transport and B5210 at the Ambarawa Railway Museum; the NZR A class of 1873 consisted of three engine types of similar specification but differing detail. They were British and New Zealand-built and several were preserved. In 1847, the government of the Cape Colony established harbour boards at its three major ports, Table Bay, Port Elizabeth and East London. While railway lines were laid at all these harbours, trains were for the most part hauled by oxen or mules; the first steam locomotives to see service at these harbours were 7 ft 1⁄4 in Brunel gauge engines which were placed in service on breakwater construction at Table Bay Harbour in 1862 and East London Harbour in 1874.