page_title: Railroad switch
section_title: Double slip
hierarchical_section_title: Railroad switch / Types / Slip switches / Double slip
caption_attribution_description: Русский: Перекрёстный стрелочный перевод на вокзале Мюнхена.English: double crossing railway switches at the München central station
context_page_description: A railroad switch, turnout, or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another, such as at a railway junction or where a spur or siding branches off.
  The switch consists of the pair of linked tapering rails, known as points, lying between the diverging outer rails. These points can be moved laterally into one of two positions to direct a train coming from the point blades toward the straight path or the diverging path. A train moving from the narrow end toward the point blades is said to be executing a facing-point movement.
  Unless the switch is locked, a train coming from either of the converging directs will pass through the points onto the narrow end, regardless of the position of the points, as the vehicle's wheels will force the points to move. Passage through a switch in this direction is known as a trailing-point movement.
  A switch generally has a straight "through" track and a diverging route. The handedness of the installation is described by the side that the diverging track leaves.
context_section_description: A double slip switch (double slip) is a narrow-angled diagonal flat crossing of two lines combined with four pairs of points in such a way as to allow vehicles to change from one straight track to the other, as well as going straight across. A train approaching the arrangement may leave by either of the two tracks on the opposite side of the crossing. To reach the third possible exit, the train must change tracks on the slip and then reverse.
  The arrangement gives the possibility of setting four routes, but because only one route can be traversed at a time, the four blades at each end of the crossing are often connected to move in unison, so the crossing can be worked by just two levers or point motors. This gives the same functionality of two points placed end to end. These compact (albeit complex) switches usually are found only in locations where space is limited, such as station throats (i.e. approaches) where a few main lines spread out to reach any of numerous platform tracks.
  In North American English, the arrangement may also be called a double switch, or more colloquially, a puzzle switch. The Great Western Railway in the United Kingdom used the term double compound points, and the switch is also known as a double compound in Victoria (Australia). In Italian, the term for a double switch is deviatoio inglese, which means English switch. Likewise, it is called Engels(e) Wissel in Dutch, and was called Engländer in German in former times.
caption: A double switch, or double slip. The points are set to connect the upper left and lower right tracks.
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