Grand unions | ||||||||||||||||||||||||||||||||||||||||||
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Full grand union
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Three-quarter union
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Half union
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Butterfly union
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| Some switches in the first three diagrams are shown combined as three-way switches, even though they would usually be built as two separate switches. | ||||||||||||||||||||||||||||||||||||||||||
A grand union is a rail track junction where two double-track railway or tramway lines cross at grade, often in a street intersection or crossroads. A total of sixteen railroad switches (sets of points) allow streetcars (or in rarer installations, trains) coming from any direction to take any of the three other directions. The same effect may be achieved with two adjacent wyes if the location allows for space.