|
North American Railroad Signals
North American railroad signals generally fall into the category of multi-headed electrically lit units displaying ''speed-based'' or ''weak route signaling''. Signals may be of the searchlight, color light, position light, or color position light types, each displaying a variety of aspects which inform the locomotive operator of track conditions so that they may keep their train under control and able to stop short of any obstruction or dangerous condition. There is no national standard or system for railroad signaling in North America. Individual railroad corporations are free to devise their own signaling systems as long as they uphold some basic regulated safety requirements. Due to the wave of mergers that have occurred since the 1960s it is not uncommon to see a single railroad operating many different types of signaling inherited from predecessor railroads. This variety can range from simple differences of hardware to completely different rules and aspects. While there h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CSX Cum-Sub 145-MAGNOLIA-CPL-brackets-winter
CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. The railroad operates approximately 21,000 route miles () of track. The company operates as the leading subsidiary of CSX Corporation, a Fortune 500 company headquartered in Jacksonville, Florida. CSX Corporation (the parent of CSX Transportation) was formed in 1980 from the merger of Chessie System and Seaboard Coast Line Industries, two holding companies which controlled a number of railroads operating in the Eastern United States. Initially only a holding company itself, the subsidiaries that made up CSX Corporation were gradually merged, with this process completed in 1987. CSX Transportation formally came into existence in 1986, as the successor of Seaboard System Railroad. In 1999, CSX Transportation acquired approximately half of Conrail, in a joint purchase with competitor Norfolk Southern Railway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slide Fence
Part of a railway signaling system, a slide fence is a fence whose purpose is to prevent trains from being derailed by rockslides in mountainous areas where rockslides may occur without warning. The fence is designed to be displaced by a rock slide, causing the signaling system to display a stop aspect on nearby signals. As an alternative, a structural fence is designed to physically stop falling rocks from reaching the tracks. Operation Mechanical The mechanical slide fence consists of a series of tensioned wires strung about 10 inches (25 cm) apart on poles. When a rock slide occurs, the rock breaks one or more of the wires. When a wire breaks, heavy weights attached to either end will fall. This mechanically triggers the protecting signals to the 'danger' position. Electrical There are two types of electrical slide fences in operation. One type of electrical slide fence consists of a series of parallel conductive wires strung about 8 inches (20 cm) apart on poles that create a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baltimore Metro SubwayLink
The Metro SubwayLink is a rapid transit line serving the greater area of Baltimore, Maryland, in the United States, and is operated by the Maryland Transit Administration. The segment in Downtown Baltimore is underground, and most of the line outside the central city is elevated or at surface grade. In , the line had a ridership of , or about per weekday as of . History The origins of the Metro Subway lie in the Baltimore Area Mass Transportation Plan, published in 1965, which envisioned six rapid transit lines radiating out from a central city loop. Planning studies from 1968 proposed a rail transit system long. As the vision was translated into reality, the original concept was trimmed to a system in the Phase 1 plan, published in 1971. This plan involved two of the original six lines: a northwest line from Downtown Baltimore to Owings Mills and a south line to Glen Burnie and the airport. Phase 1 was approved for funding by the Maryland General Assembly in 1972. In respons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid Transit
Rapid transit or mass rapid transit (MRT), also known as heavy rail or metro, is a type of high-capacity public transport generally found in urban areas. A rapid transit system that primarily or traditionally runs below the surface may be called a subway, tube, or underground. Unlike buses or trams, rapid transit systems are railways (usually electric railway, electric) that operate on an exclusive right-of-way (transportation), right-of-way, which cannot be accessed by pedestrians or other vehicles, and which is often grade-separated in tunnels or on elevated railways. Modern services on rapid transit systems are provided on designated lines between rapid transit station, stations typically using electric multiple units on rail tracks, although some systems use guided rubber tires, magnetic levitation (''maglev''), or monorail. The stations typically have high platforms, without steps inside the trains, requiring custom-made trains in order to minimize gaps between train a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Restrictive
In semantics, a modifier is said to be restrictive (or ''defining'') if it restricts the reference of its head. For example, in "the red car is fancier than the blue one", ''red'' and ''blue'' are restrictive, because they restrict which cars ''car'' and ''one'' are referring to. ("The car is fancier than the one" would make little sense.) By contrast, in "John's beautiful mother", ''beautiful'' is non-restrictive; "John's mother" identifies her sufficiently, whereas "beautiful" only serves to add more information. Restrictive modifiers are also called ''defining'', ''identifying'', ''essential'', or ''necessary''; non-restrictive ones are also called ''non-defining'', ''non-identifying'', ''descriptive'', or ''unnecessary'' (though this last term can be misleading). In certain cases, generally when restrictiveness is marked syntactically through the lack of commas, restrictive modifiers are called ''integrated'' and non-restrictive ones are called ''non-integrated'' or ''supplem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstate Commerce Commission
The Interstate Commerce Commission (ICC) was a regulatory agency in the United States created by the Interstate Commerce Act of 1887. The agency's original purpose was to regulate railroads (and later trucking) to ensure fair rates, to eliminate rate discrimination, and to regulate other aspects of common carriers, including interstate bus lines and telephone companies. Congress expanded ICC authority to regulate other modes of commerce beginning in 1906. Throughout the 20th century, several of ICC's authorities were transferred to other federal agencies. The ICC was abolished in 1995, and its remaining functions were transferred to the Surface Transportation Board. The Commission's five members were appointed by the President with the consent of the United States Senate. This was the first independent agency (or so-called ''Fourth Branch''). Creation The ICC was established by the Interstate Commerce Act of 1887, which was signed into law by President Grover Cleveland. The cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derail
A derail or derailer is a device used to prevent fouling (blocking or compromising) of a rail track (or collision with anything present on the track, such as a person, or a train) by unauthorized movements of trains or unattended rolling stock. The device works by derailing the equipment as it rolls over or through it. Although accidental derailment is damaging to equipment and track, and requires considerable time and expense to remedy, derails are used in situations where there is a risk of greater damage to equipment, injury or death if equipment is allowed to proceed past the derail point. Applications Derails may be applied: *where sidings meet main lines or other through tracks *at junctions or other crossings to protect the interlocking against unauthorized movement *temporarily at an area where crews are working on a rail line *approaching a drawbridge, dead end, or similar hazard. Design There are four basic forms of derail. Wedge The most common form is a wedge- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trainyard
A classification yard (American and Canadian English (Canadian National Railway use)), marshalling yard (British, Hong Kong, Indian, Australian, and Canadian English (Canadian Pacific Railway use)) or shunting yard (Central Europe) is a railway yard found at some freight train stations, used to separate railway cars onto one of several tracks. First the cars are taken to a track, sometimes called a ''lead'' or a ''drill''. From there the cars are sent through a series of switches called a ''ladder'' onto the classification tracks. Larger yards tend to put the lead on an artificially built hill called a ''hump'' to use the force of gravity to propel the cars through the ladder. Freight trains that consist of isolated cars must be made into trains and divided according to their destinations. Thus the cars must be shunted several times along their route in contrast to a unit train, which carries, for example, cars from the plant to a port, or coal from a mine to the power plant. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doublet Lens
In optics, a doublet is a type of lens made up of two simple lenses paired together. Such an arrangement allows more optical surfaces, thicknesses, and formulations, especially as the space between lenses may be considered an "element". With additional degrees of freedom, optical designers have more latitude to correct more optical aberrations more thoroughly. Types Doublets can come in many forms, though most commercial doublets are achromats, which are optimized to reduce chromatic aberration while also reducing spherical aberration and other optical aberrations. The lenses are made from glasses with different refractive indices and different amounts of dispersion. Often one element is made from crown glass and the other from flint glass. This combination produces a better image than a simple lens. Some Trilobites, which are now extinct, had natural doublet lenses in their eyes. Apochromats can also be made as doublets. Doublets can be air-spaced, cemented, or "oiled". Oi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incandescent Lamp
An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated until it glows. The filament is enclosed in a glass bulb with a vacuum or inert gas to protect the filament from oxidation. Current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting. Incandescent bulbs are much less efficient than other types of electric lighting, converting le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bi-directional Railway Signalling
The application of railway signals on a rail layout is determined by various factors, principally the location of points of potential conflict, as well as the speed and frequency of trains and the movements they require to make. Non-provision of signals Before discussing the application of signals, it is useful to highlight some situations where signals are ''not'' required: * Sidings generally need not be signalled, as all movements within them are made cautiously at low speed. * Tram lines frequently employ "running on sight" without any signals (similar to road traffic). * Where movement authorities are passed to drivers exclusively by means other than fixed signals (e.g. by written or verbal authority), token, or cab signalling. Purpose of signals Signals exist primarily to pass instructions and information to drivers of passing trains. The driver interprets the signal's indication and acts accordingly. The most important indication is 'danger', which means 'stop'. N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overhead Lines
An overhead line or overhead wire is an electrical cable that is used to transmit electrical energy to electric locomotives, trolleybuses or trams. It is known variously as: * Overhead catenary * Overhead contact system (OCS) * Overhead equipment (OHE) * Overhead line equipment (OLE or OHLE) * Overhead lines (OHL) * Overhead wiring (OHW) * Traction wire * Trolley wire This article follows the International Union of Railways in using the generic term ''overhead line''. An overhead line consists of one or more wires (or rails, particularly in tunnels) situated over rail tracks, raised to a high electrical potential by connection to feeder stations at regular intervals. The feeder stations are usually fed from a high-voltage electrical grid. Overview Electric trains that collect their current from overhead lines use a device such as a pantograph, bow collector or trolley pole. It presses against the underside of the lowest overhead wire, the contact wire. Current collectors are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Overhead Lines")