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Hillclimbing (railway)
Hillclimbing is a problem faced by railway systems when a load must be carried up an incline. While railways have a great ability to haul very heavy loads, this advantage is only significant when the tracks are fairly level. As soon as the gradients increase, the tonnage that can be hauled is greatly diminished. History Early tramways and railways were laid out with very gentle grades because locomotive and horse haulage were so low in tractive effort. The only exception would be with a line that was downhill all the way for loaded traffic. Brakes were very primitive at this early stage. Where a railway has to cross a range of mountains, it is important to lower the summit as much as possible, as this reduces the steepness of the gradients on either side. This can be done with a summit tunnel or a deep summit cutting. A summit tunnel can lower the summit even more, and steeper hills result in shorter tunnels. Also, tunnels cost the same no matter how much overburden there is, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grade (slope)
The grade (also called slope, incline, gradient, mainfall, pitch or rise) of a physical feature, landform or constructed line refers to the tangent of the angle of that surface to the horizontal. It is a special case of the slope, where zero indicates horizontality. A larger number indicates higher or steeper degree of "tilt". Often slope is calculated as a ratio of "rise" to "run", or as a fraction ("rise over run") in which ''run'' is the horizontal distance (not the distance along the slope) and ''rise'' is the vertical distance. Slopes of existing physical features such as canyons and hillsides, stream and river banks and beds are often described as grades, but typically grades are used for human-made surfaces such as roads, landscape grading, roof pitches, railroads, aqueducts, and pedestrian or bicycle routes. The grade may refer to the longitudinal slope or the perpendicular cross slope. Nomenclature There are several ways to express slope: # as an ''angle'' of inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horseshoe Curve (railway)
A horseshoe curve is a class of climbing curve in a roadbed which reverses turn direction (inflection) twice on either side of a single tight curve that varies through an angle of about 180 degrees or more. Such curves are more commonly found in a railway line but are also used in roads. The characteristic U shape, or even slight balloon shape, of such a curve resembles a horseshoe. On roadways, particularly tight versions of such curves are typically called hairpin turns. Theory A horseshoe curve is a means to lengthen an ascending or descending grade and thereby reduce the maximum gradient. Grade or gradient is defined as the rise divided by the run (length) or distance, so in principle such curves add to length for the same altitude gain, just as would a climbing spiral around one or more peaks, or a climbing traverse (cutting) wrapping around an end of a ridge. If the straight route between two points is too steep to climb, a more circuitous route will increase the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lickey Incline
The Lickey Incline, south of Birmingham, is the steepest sustained main-line railway incline in Great Britain. The climb is a gradient of 1 in 37.7 (2.65% or 26.5‰ or 1.52°) for a continuous distance of two miles (3.2 km). Constructed originally for the Birmingham and Gloucester Railway (B&GR) and opened in 1840 it is located on the Cross Country Route between and stations in Worcestershire. In earlier times many trains required the assistance of banking locomotives with associated logistical considerations to ensure that the train reached the top; now only the heaviest of freight trains require such assistance. History and geography A survey by Isambard Kingdom Brunel in 1832 for a line between Birmingham and Gloucester followed a longer route well to the east with a maximum 1 in 300 gradient avoiding population centres, the plan lapsed with the cost being deemed too high. In 1836 William Moorsom was engaged on a ''no success - no fee'' to survey a suitable r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funicular Railway
A funicular (, , ) is a type of cable railway system that connects points along a railway track laid on a steep slope. The system is characterized by two counterbalanced carriages (also called cars or trains) permanently attached to opposite ends of a haulage cable, which is looped over a pulley at the upper end of the track. The result of such a configuration is that the two carriages move synchronously: as one ascends, the other descends at an equal speed. This feature distinguishes funiculars from inclined elevators, which have a single car that is hauled uphill. The term ''funicular'' derives from the Latin word , the diminutive of , meaning 'rope'. Operation In a funicular, both cars are permanently connected to the opposite ends of the same cable, known as a ''haul rope''; this haul rope runs through a system of pulleys at the upper end of the line. If the railway track is not perfectly straight, the cable is guided along the track using sheaves – unpowered pulleys that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rail Surface Treatment
Sandite is a substance used on railways in the UK, Ireland, US, the Netherlands and Belgium to combat leaves on the line, which can cause train wheels to slip and become damaged with flat spots. Sandite consists of a mixture of sand, antifreeze and steel shot. Leaf build up on the railhead can also cause signalling issues and 'disappearing trains' on the rail control systems (because of the electrically insulating effect of the leaves, which can prevent operation of track circuits). British Rail conducted research, in 1976, to determine the suitability of Sandite for use as an adhesion improver. Application Sandite is usually applied by a special train which first clears fallen leaves from the rails using high-pressure water, then sprays the sandite onto the rail surface. To assist the staff on the Sandite train in locating the sites concerned, in England and Wales black on yellow lineside markers were installed: *The first sign, with three stripes gives advance warning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Car (railway)
A cable car (usually known as a cable tram outside North America) is a type of cable railway used for Public transport, mass transit in which rail cars are hauled by a continuously moving Wire rope, cable running at a constant speed. Individual cars stop and start by releasing and gripping this cable as required. Cable cars are distinct from funiculars, where the cars are permanently attached to the cable. History The first cable-operated railway, employing a moving rope that could be picked up or released by a grip on the cars was the Fawdon Wagonway in 1826, a colliery railway line. The London and Blackwall Railway, which opened for passengers in east London, England, in 1840 used such a system. The rope available at the time proved too susceptible to wear and the system was abandoned in favour of steam locomotives after eight years. In America, the first cable car installation in operation probably was the IRT Ninth Avenue Line, West Side and Yonkers Patent Railway i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Railway
An atmospheric railway uses differential air pressure to provide power for propulsion of a railway vehicle. A static power source can transmit motive power to the vehicle in this way, avoiding the necessity of carrying mobile power generating equipment. The air pressure, or partial vacuum (i.e., negative relative pressure) can be conveyed to the vehicle in a continuous pipe, where the vehicle carries a piston running in the tube. Some form of re-sealable slot is required to enable the piston to be attached to the vehicle. Alternatively the entire vehicle may act as the piston in a large tube or be coupled electromagnetically to the piston. Several variants of the principle were proposed in the early 19th century, and a number of practical forms were implemented, but all were overcome by unforeseen disadvantages and discontinued within a few years. A modern proprietary system has been developed and is in use for short-distance applications. Porto Alegre Metro airport connection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shay Locomotive
The Shay locomotive is a geared steam locomotive that originated and was primarily used in North America. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a ''geared steam locomotive''. Although the design of Ephraim Shay's early locomotives differed from later ones, there is a clear line of development that joins all Shays. Shay locomotives were especially suited to logging, mining and industrial operations and could operate successfully on steep or poor quality track. Development Ephraim Shay (1839–1916), was a schoolteacher, a clerk in an American Civil War hospital, a civil servant, a logger, a merchant, a railway owner, and an inventor who lived in Michigan. In the 1860s, he became a logger and wanted a better way to move logs to the mill than on winter snow sleds. He built his own tramway in 1875, on gauge track on wooden ties, allowing him to log all year round. Two years later he develope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geared Steam Locomotive
A geared steam locomotive is a type of steam locomotive which uses gearing, usually reduction gearing, in the drivetrain, as opposed to the common directly driven design. This gearing is part of the machinery within the locomotive and should not be confused with the pinion that propels a rack locomotive along the rack between the rails. The geared steam locomotives that have been built have been for conventional track, relying on the adhesion between wheels and rail. Explanation and rationale The steam locomotive, as commonly employed, has its pistons directly attached to cranks on the driving wheels; thus, there is no gearing, one revolution of the driving wheels is equivalent to one revolution of the crank and thus two power strokes per piston (steam locomotives are almost universally double-acting, unlike the more familiar internal combustion engine). The maximum rotational speed is fairly fixed for a given engine technology. Given the lack of any variable-ratio transmis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stationary Engine
A stationary engine is an engine whose framework does not move. They are used to drive immobile equipment, such as pumps, generators, mills or factory machinery, or cable cars. The term usually refers to large immobile reciprocating engines, principally stationary steam engines and, to some extent, stationary internal combustion engines. Other large immobile power sources, such as steam turbines, gas turbines, and large electric motors, are categorized separately. Stationary engines were once widespread in the era when each factory or mill generated its own power, and power transmission was mechanical (via line shafts, belts, gear trains, and clutches). Applications for stationary engines have declined since electrification has become widespread; most industrial uses today draw electricity from an electrical grid and distribute it to various individual electric motors instead. Engines that operate in one place, but can be moved to another place for later operation, are calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funicular
A funicular (, , ) is a type of cable railway system that connects points along a railway track laid on a steep slope. The system is characterized by two counterbalanced carriages (also called cars or trains) permanently attached to opposite ends of a haulage cable, which is looped over a pulley at the upper end of the track. The result of such a configuration is that the two carriages move synchronously: as one ascends, the other descends at an equal speed. This feature distinguishes funiculars from inclined elevators, which have a single car that is hauled uphill. The term ''funicular'' derives from the Latin word , the diminutive of , meaning 'rope'. Operation In a funicular, both cars are permanently connected to the opposite ends of the same cable, known as a ''haul rope''; this haul rope runs through a system of pulleys at the upper end of the line. If the railway track is not perfectly straight, the cable is guided along the track using sheaves – unpowered pulleys tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Railway
Cable may refer to: Mechanical * Nautical cable, an assembly of three or more ropes woven against the weave of the ropes, rendering it virtually waterproof * Wire rope, a type of rope that consists of several strands of metal wire laid into a helix ** Arresting cable, part of a system used to rapidly decelerate an aircraft as it lands ** Bowden cable, a mechanical cable for transmitting forces * Rope generally, especially a thick, heavy ("cable laid") variety Transmission * Electrical cable, an assembly of one or more wires which may be insulated, used for transmission of electrical power or signals ** Coaxial cable, an electrical cable comprising an inner conductor surrounded by a flexible, tubular insulating layer, coated or surrounded by a tubular conducting shield ** Power cable, a cable used to transmit electrical power ** Submarine communications cable, a cable laid on the sea bed to carry telecommunication signals between land-based stations * Fiber-optic cable, a cable co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
