The wheels of flangeway wagons were plain, but they could not operate on ordinary roads as the narrow rims would dig into the surface.
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An electro-mechanical treadle retains a small arm that lies across the flangeway of a rail. When it is depressed, an electrical circuit controller within the unit changes its output. It remains depressed for a period of several seconds, so that a train with many axles does not unduly damage the unit.
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Flange-bearing frog (bottom, center) used in street railway trackage in Liberec, Czech Republic. Note the polishing in the flangeway indicating contact with the wheel flange. Flange-bearing frogs have been used by street railways for more than 200 years as a means of reducing noise pollution in populated urban settings.Barkan, Dr. Christopher.
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Treadles are commonly used to operate fully automatic level crossings since they give far more reliable and accurate detection of a train than track circuits alone, which is important when there is only just over 30 seconds between the train "striking in" (passing the treadle which starts the crossing sequence) and passing the crossing. A small treadle operates this flangeway greaser.
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This also eliminates the problem of switch failures. In a frog gauntlet, one rail crosses over a rail on the adjacent track. A frog is used to provide the flangeway for the crossing tracks. The train taking the gauntlet runs over the frog onto the parallel rails, passes through the gauntlet area, and passes over another frog to return to the original line.
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Cross section of a grooved tram rail Difference in form and profile of the wheel and the rail of a train (left, blue) and a tram (right, green). Where a rail is laid in a Road surface (pavement) or within grassed surfaces, there has to be accommodation for the flange. This is provided by a slot called the flangeway. The rail is then known as grooved rail, groove rail, or girder rail.
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Tramway track is used on tramways or light rail operations. Grooved rails (or girder rails) are often used to provide a protective flangeway in the trackwork in city streets. Like standard rail tracks, tram tracks consist of two parallel steel rails. Tram rails can be placed on several surfaces, such as with standard rails on sleepers like railway tracks, or with grooved rails on concrete sleepers into street surfaces (pavement) for street running.
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P4, otherwise known as Protofour, or "18.83", is a close to exact 4 mm:1 ft replica of real-life track and wheel dimensions. The gauge of track built to these standards is 18.83 mm. Along with EM Gauge It is also a popular choice for finescale modellers working today. The main advantage of P4 over the other 4 mm standards is that the wheel flanges are approximately to scale and the flangeway gaps on P&C; work are also close to scale.
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The flangeway has the railhead on one side and the guard on the other. The guard carries no weight, but may act as a checkrail. Grooved rail was invented in 1852 by Alphonse Loubat, a French inventor who developed improvements in tram and rail equipment, and helped develop tram lines in New York City and Paris. The invention of grooved rail enabled tramways to be laid without causing a nuisance to other road users, except unsuspecting cyclists, who could get their wheels caught in the groove.
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Block rail is a lower profile form of girder guard rail with the web eliminated. In profile it is more like a solid form of bridge rail, with a flangeway and guard added. Simply removing the web and combining the head section directly with the foot section would result in a weak rail, so additional thickness is required in the combined section. A modern block rail with a further reduction in mass is the LR55 rail which is polyurethane grouted into a prefabricated concrete beam.
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EM was originally defined to use 18mm as the track gauge (hence the name: Eighteen Millimetres). This was revised, and today EM gauge uses an track gauge, which is closer to accurate but not fully to scale. It was developed as an early improvement on the standard OO system. It is still popular with FineScale modellers today because it utilises larger than scale flanges on the wheels of rolling stock, and because point and crossing (P&C;) work is a little easier due to an overscale flangeway clearance.
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A reconstructed section of flangeway track as used by Richard Trevithick's pioneering locomotives at Coalbrookdale and Merthyr The plates of a plateway generally rested on stone blocks or sleepers, which served to spread the load over the ground, and to maintain the gauge (the distance between the rails or plates). The plates were usually made from cast iron and had differing cross sections depending on the manufacturer. They were often very short, typically about long, able to stretch only from one block to the next. The L section plateway was introduced for underground use by John Curr of Sheffield Park Colliery in about 1787.
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This is most noticeable in photographs of the model where in many cases is it almost impossible to detect that you are looking at a model, as opposed to the real thing. The disadvantages of near to scale flanges and flangeway crossings are that the trackwork has to be laid and built to very close tolerances and needs to be flat. If this is not the case then the reliability of rolling stock on the trackwork is compromised leading to poor running and derailments. This problem can, to an extent, be mitigated by the use of some form of suspension system in the locomotives and rolling stock used on the layout.
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Southern Pacific Railroad flanger in Oakridge, Oregon A Batten Kill Railroad flanger A French railway flanger with four blades for bi-directional operation An earlier French flanger with a single blade A flanger (also known as a scraper or digger) is a railroad car that clears the space between the rails, generally of ice and snow. While a wedge plow can remove snow above the surface of the rails, the flanger removes snow and ice from below the surface of the rails where the railway wheel flanges fit. Railway locomotives and cars can be derailed if the flangeway is filled. The flanger blades are lowered below the head of the rail.
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Overview of Flange-Bearing Frogs. Presentation given at semiweekly William W. Hay Railroad Engineering Seminar, University of Illinois, Urbana, IL. Because the flange rides on a continuous surface in a fully flange-bearing mode, the impact loads generated by the flangeway gap of conventional frogs are eliminated. This reduces maintenance and extends the life of the frog, which leads to an operational cost savings that exceeds the increase in initial costs, when compared to conventional frogs. As previously mentioned, flange- bearing frogs are quieter than conventional frogs—again, because of the reduced impact loads—which provides a potential benefit when implemented near residential areas.
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