When the fork tip faces the fork root, the left side of the line is equipped with a left-hand device (also called a forward device), the switch machine extends to the right, and the right side of the line is equipped with a right-hand device (also called a backward device), and the switch machine extends to the left. When a switch bends to the left, it is called left bend, left bend is called left straight, right bend is called right bend, and right bend is called right straight. According to this, the drilling position of the second angle steel can be confirmed.
Laying technology
The turnout laying position shall be laid as designed. Under difficult conditions, through the overall research, under the condition of not affecting the effective length of the track and not changing other operating conditions, the laying position of the turnout can be moved back and forth by no more than 6.25m, but the maximum moving amount should not be greater than 0.5m at the stations above the section station, especially the turnout in the throat area.
The rail type of turnouts on the main line of the national railway should be the same as that of the main line, and the rail type of turnouts on station lines, local railways, special lines and railway special lines can not be lower than that of the main line connected with them. When the turnout rail type is different from the connecting rail type, when laying the turnout, the rail with the same length as the turnout 1 section should be laid before and after the turnout, and the length can be reduced to 4.5m in case of difficulty.
When laying turnouts, when the distance between two turnouts is less than 9 meters, the rail types of turnouts should be consistent or the two turnouts should be directly connected with special-shaped rails. For turnouts with track circuits, the distance between two turnouts with different track types should still meet the requirements of setting insulating joints. Insulating joints should not be set at joints of different rail types.