In rail transport, track gauge or track gage is the spacing of the rails on a railway track and is measured between the inner faces of the load-bearing rails. All vehicles on a rail network must have running gear, compatible with the track gauge, in the earliest days of railways the selection of a proposed railway's gauge was a key issue; as the dominant parameter determining interoperability, it is still used as a descriptor of a route or network. In some places there is a distinction between the nominal gauge and the actual gauge, due to divergence of track components from the nominal. Railway engineers use a device, like a caliper, to measure the actual gauge, this device is referred to as a track gauge; the terms structure gauge and loading gauge, both used, have little connection with track gauge. Both refer to two-dimensional cross-section profiles, surrounding the track and vehicles running on it; the structure gauge specifies the outline into which altered structures must not encroach.
The loading gauge is the corresponding envelope within which rail vehicles and their loads must be contained. If an exceptional load or a new type of vehicle is being assessed to run, it is required to conform to the route's loading gauge. Conformance ensures. In the earliest days of railways, single wagons were manhandled on timber rails always in connection with mineral extraction, within a mine or quarry leading from it. Guidance was not at first provided except by human muscle power, but a number of methods of guiding the wagons were employed; the spacing between the rails had to be compatible with that of the wagon wheels. The timber rails wore rapidly. In some localities, the plates were made L-shaped, with the vertical part of the L guiding the wheels; as the guidance of the wagons was improved, short strings of wagons could be connected and pulled by horses, the track could be extended from the immediate vicinity of the mine or quarry to a navigable waterway. The wagons were built to a consistent pattern and the track would be made to suit the wagons: the gauge was more critical.
The Penydarren Tramroad of 1802 in South Wales, a plateway, spaced these at 4 ft 4 in over the outside of the upstands. The Penydarren Tramroad carried the first journey by a locomotive, in 1804, it was successful for the locomotive, but unsuccessful for the track: the plates were not strong enough to carry its weight. A considerable progressive step was made. Edge rails required a close match between rail spacing and the configuration of the wheelsets, the importance of the gauge was reinforced. Railways were still seen as local concerns: there was no appreciation of a future connection to other lines, selection of the track gauge was still a pragmatic decision based on local requirements and prejudices, determined by existing local designs of vehicles. Thus, the Monkland and Kirkintilloch Railway in the West of Scotland used 4 ft 6 in; the Arbroath and Forfar Railway opened in 1838 with a gauge of 5 ft 6 in, the Ulster Railway of 1839 used 6 ft 2 in Locomotives were being developed in the first decades of the 19th century.
His designs were so successful that they became the standard, when the Stockton and Darlington Railway was opened in 1825, it used his locomotives, with the same gauge as the Killingworth line, 4 ft 8 in. The Stockton and Darlington line was immensely successful, when the Liverpool and Manchester Railway, the first intercity line, was built, it used the same gauge, it was hugely successful, the gauge, became the automatic choice: "standard gauge". The Liverpool and Manchester was followed by other trunk railways, with the Grand Junction Railway and the London and Birmingham Railway forming a huge critical mass of standard gauge; when Bristol promoters planned a line from London, they employed the innovative engineer Isambard Kingdom Brunel. He decided on a wider gauge, to give greater stability, the Great Western Railway adopted a gauge of 7 ft eased to 7 ft 1⁄4 in; this became known as broad gauge. The Great Western Railway was successful and was expanded and through friendly associated companies, widening the scope of broad gauge.
At the same time, other parts of Britain built railways to standard gauge, British technology was exported to European countries and parts of North America using standard gauge. Britain polarised into two areas: those that used standard gauge. In this context, standard gauge was referred to as "narrow gauge" to indicate the contrast; some smaller concerns selected other non-standard gauges: the Eastern Counties Railway adopted 5 ft. Most of them converted to standard gauge at an early date, but the GWR's broad gauge continued to grow; the larger railway companies wished to expand geographically, large areas were considered to be under their control. When a new
Condensing steam locomotive
A condensing steam locomotive is a type of locomotive designed to recover exhaust steam, either in order to improve range between taking on boiler water, or to reduce emission of steam inside enclosed spaces. The apparatus takes the exhaust steam that would be used to produce a draft for the firebox, routes it through a heat exchanger, into the boiler water tanks. Installations vary depending on the purpose and the type of locomotive to which it is fitted, it differs from the usual closed cycle condensing steam engine, in that the function of the condenser is either to recover water, or to avoid excessive emissions to the atmosphere, rather than maintaining a vacuum to improve both efficiency and power. Unlike the surface condenser used on a steam turbine or marine steam engine, the condensing apparatus on a steam locomotive does not increase the power output, rather it decreases due to a reduction of airflow to the firebox that heats the steam boiler. In fact it may reduce it considerably.
Condensing the steam from a high volume gas to a low volume liquid causes a significant pressure drop at the exhaust, which would add additional power in most steam engines. Whilst more power is available by expanding down to a vacuum, the power output is greatly reduced compared to a conventional steam locomotive on account of the lower air flow through the firebox, as there is now no waste steam to eject into the firebox exhaust in order to pull more air into the firebox air intake. In order to produce similar power, air to the firebox must be provided by a steam driven or mechanically driven fan; this cancels out any improvement in efficiency. The temperature of the exhaust steam is greater than typical stationary or ship-based steam plant of similar power due to having fewer waste recovery stages, as ships have an additional low pressure stage or a low speed turbine. Waste heat on modern steam plants is recovered using heat exchangers. However, condensing locomotives do not have this benefit due to the waste heat being expelled to the surrounding air and not being recovered, therefore none of the energy in the waste steam is recovered to do mechanical work.
In many conditions the temperature gradient is much worse due to using air instead of having an abundant source of cooling water, the case with naval or stationary steam power plants. The Anderson condensing system reduces these losses by only cooling the waste steam before compressing it into condensate pumping the high temperature condensate back into the boiler in order to recover the unused waste heat; this reduces energy waste. Because of the high temperature in a locomotive condenser and the rejection of the heat to the air, the potential improvement in thermal efficiency expected from including the condenser in the cycle is not realised within the space constraints of a typical locomotive. Indeed, losses due to viscous friction in the condenser piping, having to pump the condensate back into the boiler is to reduce the power output over what was achievable from venting to atmosphere; these restrictions do not apply to marine or stationary steam engines due to not having size or weight restrictions.
Ships had massive waste steam recovery systems, such as the 400 ton waste steam turbine used to recover low 6psi waste steam on the Titanic and its sister ships. This is several times the weight of an entire locomotive, so is not feasible as a form of waste steam recovery for locomotives. A drawback of condensing the exhaust steam is that it is no longer available to draw the fire, by use of the blastpipe; the draught must thus be generated instead by a steam-driven fan. Where possible, this has been arranged to use exhaust steam, although in some cases live steam was required, with extra steam and thus fuel consumption. Steam locomotive condensers may be air-cooled. Here, the exhaust steam is blown into cold water in the locomotive's water tanks. A non-return system must be fitted, to prevent water from the tanks being drawn into the cylinders when the steam is shut off; this system was used for locomotives working in tunnels. Here, the exhaust steam is blown into an air-cooled radiator, similar to that used for the cooling system of an internal combustion engine.
This system was used on large tender engines. The Anderson condensing system uses an air-cooled condenser but the steam is only condensed to form an aerosol of water droplets in steam; this aerosol is liquified by pressure, using a specially-designed boiler feed pump. A fuel saving of nearly 30% was claimed for the Anderson system but this seems paradoxical. One would expect a higher fuel consumption because of the power required to compress the aerosol; the reason this is possible is due to Carnot's theorem, which states that pumping heat requires less energy than producing the heat itself. A similar effect known as Vapor-compression desalination was used for desalination of water. Instead of returning the condensate water to the boiler, the hot compressed condensate is passed through a heat exchanger to return heat to the boiler released as clean drinking water, it is one of the most efficient processes used to desalinate water. There are two usual reasons for fitting condensing equipment - reducing exhaust emissions and increasing range.
Developed for the Metropolitan Railway to allow their locomotives to work the tunnels of the London Underground. This system was developed by Beyer Peacock. Steam is diver
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
The Caledonian Railway was a major Scottish railway company. It was formed in the early 19th century with the objective of forming a link between English railways and Glasgow, it progressively extended its network and reached Edinburgh and Aberdeen, with a dense network of branch lines in the area surrounding Glasgow. It was absorbed into the London and Scottish Railway in 1923. Many of its principal routes are still used, the original main line between Carlisle and Glasgow is in use as part of the West Coast Main Line railway. In the mid-1830s railways in England evolved from local concerns to longer routes that connected cities, became networks. In Scotland it was clear that this was the way forward, there was a desire to connect the central belt to the incipient English network. There was controversy over the route that such a line might take, but the Caledonian Railway was formed on 31 July 1845 and it opened its main line between Glasgow and Carlisle in 1848, making an alliance with the English London and North Western Railway.
In the obituary of the engineer Richard Price-Williams written in 1916 the contractor of the Caledonian Railway is stated to be Thomas Brassey and the civil engineer George Heald. Although the company was supported by Scottish investors, more than half of its shares were held in England. Establishing itself as an inter-city railway, the Caledonian set about securing territory by leasing other authorised or newly built lines, fierce competition developed with other, larger Scottish railways the North British Railway and the Glasgow and South Western Railway; the company remained less than successful in others. A considerable passenger traffic developed on the Firth of Clyde serving island resorts, fast boat trains were run from Glasgow to steamer piers. In 1923 the railways of Great Britain were "grouped" under the Railways Act 1921 and the Caledonian Railway was a constituent of the newly formed London Midland and Scottish Railway, it extended from Aberdeen to Portpatrick, from Oban to Carlisle, running express passenger services and a heavy mineral traffic.
In the closing years of the 18th century, the pressing need to bring coal cheaply to Glasgow from the plentiful Monklands coalfield had been met by the construction of the Monkland Canal, opened throughout in 1794. This encouraged development of the coalfield but dissatisfaction at the monopoly prices said to be exacted by the canal led to the construction of the Monkland and Kirkintilloch Railway, Scotland's first public railway. Development of the use of blackband ironstone by David Mushet, the invention of the hot blast process of iron smelting by James Beaumont Neilson in 1828 led to a huge and rapid increase in iron production and demand for the ore and for coal in the Coatbridge area; the industrial development led to the construction of other railways contiguous with the M&KR, in particular the Garnkirk and Glasgow Railway and the Wishaw and Coltness Railway. These two lines worked in harmony, merging to form the Glasgow and Coatbridge Railway in 1841, competing with the M&KR and its allies.
All these lines used the local track gauge of 4 ft 6 in, they were referred to as the coal lines. During this period, the first long-distance railways were opened in England, it was followed by the London and Birmingham Railway in 1838 and the Grand Junction Railway in 1837, the North Union Railway reaching Preston in 1838, so that London was linked with the Lancashire and West Midlands centres of industry. It was desirable to connect central Scotland into the emerging network. At first it was assumed that only one route from Scotland to England would be feasible, there was considerable controversy over the possible route. A major difficulty was the terrain of the Southern Uplands: a route running through the hilly lands would involve steep and lengthy gradients that were challenging for the engine power of the time. Many competing schemes were put forward, not all of them well thought out, two successive Government commissions examined them. However, they did not have mandatory force, after considerable rivalry, the Caledonian Railway obtained an authorising Act of Parliament on 31 July 1845, for lines from Glasgow and Edinburgh to Carlisle.
The share capital was to be £1,800,000. The Glasgow and Edinburgh lines combined at Carstairs in Clydesdale, the route crossed over Beattock summit and continued on through Annandale; the promoters had engaged in a frenzy of provisional acquisitions of other lines being put forward or being constructed, as they considered it was vital to secure territory to their own control and to exclude competing concerns as far as possible. However, if they hoped to operate the only Anglo-Scottish route, they were disappointed; the North British Railway opened between Edinburgh and Berwick-upon-Tweed on 22 June 1846, forming part of what has become the East Coast Main Line
Caledonian Railway 294 and 711 Classes
The Caledonian Railway 294 and 711 Classes were 0-6-0 steam locomotives designed by Dugald Drummond for the Caledonian Railway and introduced in 1883. After Drummond's retirement, construction of the class continued under Lambie and McIntosh. All 244 locomotives survived to be absorbed by the London and Scottish Railway in 1923 and 238 survived into British Railways ownership in 1948. 294 Class711 ClassThe BR number series are not continuous because some locomotives were withdrawn before 1948. Locomotives of the Caledonian Railway
John F. McIntosh
John Farquharson McIntosh was a Scottish engineer. He was Chief Mechanical Engineer of the Caledonian Railway from 1895-1914, he was succeeded by William Pickersgill. Born in Farnell, Scotland, in February 1846, MacIntosh would be famous for working at St. Rollox railway works, in Springburn, in Glasgow. John F. McIntosh became an apprentice with the Scottish North Eastern Railway, at the Arbroath workshops, at the age of 14. In 1865 he passed out as a fireman and in 1867 he qualified as a driver and moved to Montrose. By this time he was employed by the Caledonian Railway which had taken over the SNER in 1866, he lost his right hand in an accident in 1876 or 1877. At about the same time he became Locomotive Inspector for the northern section of the CR, he was given responsibility for all locations north of Greenhill. By 1881 he was living in Perth. Several appointments followed - Locomotive Foreman at Aberdeen and Polmadie. Lambie died on 1 February 1895 and McIntosh replaced him as Chief Mechanical Engineer.
McIntosh's most famous design is the Dunalastair Class 4-4-0. Other designs include: Caledonian Railway 19, 92 and 439 classes 0-4-4T Caledonian Railway 29 & 782 classes 0-6-0T Caledonian Railway 498 Class 0-6-0T Caledonian Railway 652 and 812 classes 0-6-0 PreservationTwo McIntosh locomotives are preserved: 439 Class, humber 419 at the Bo'ness and Kinneil Railway 812 Class, number 828 at the Strathspey Railway He obtained patents for a spark arrestor and a gauge glass protector. List of patentsGB189823849, published 31 May 1899, Improvements in or relating to railway wagon brakes GB190004019, published 16 February 1901, Improvements in or relating to railway wagon brakes GB190207009, published 22 April 1903, Improvements in and connected with engine valve gear GB190822998, published 28 October 1909, Improvements in or relating to the smoke boxes of locomotive boilers He married Jeanie Fleming Logan, a close relative to author Ian Fleming, they had 3 sons and 4 daughters. McIntosh died while working at St. Rollox railway works, on 6 February 1918, 22 days before his 72nd birthday.
The cause of death was never confirmed. Locomotives of the Caledonian Railway Locomotives of the London and Scottish Railway