TRAIN TRACK JUNCTION

ABOUT ALL TRAIN TRACK JUNCTION

1. TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS Presenting by : P.RAMA CHANDRA KIRAN

2. 13/07/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 2 Track Junction Track junctions are formed by the combination of points and crossings. Their main objective is to transfer rail vehicles from one track to another or to enable them to cross from one track to another.  Depending upon the requirements of traffic. Track Junction

3. 13/07/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 3 Types of track junctions  There can be several types of track junctions with simple track layouts. The most commonly used layouts Or Track Junction Types discussed in the following are

4. Turnout Of Similar Flexure A turnout of similar flexure continues to run in the same direction as the main line curve even after branching off from it. The degree of the turnout curve will be higher than that of the main line curve. The degree and radius of the turnout curve given by the formulae 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 4 Turnout Of Similar Flexure

5. Turnout Of Contrary Flexure A turnout of contrary flexure takes off towards the direction opposite to that of the main line curve. In this case, the degree and radius of the turnout curve given by the following formulae.   Dm is the degree of the rail of the main track on which the crossing lies, i.e., the outer rail in Fig. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 5 Turnout Of Contrary Flexure

6. Symmetrical Split “Alien a straight track splits up in two different directions with equal radii, the layout known as a symmetrical split. In other words, a symmetrical spat is a contrary flexure in which the radii of the two curves are the same. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 6 Symmetrical Split

7. Three-Throw Switch In a three-throw arrangement, two turnouts take off from the same point of a main line track. A three-throw switch has two switches and each switch has two tongue rails placed side by side. There is a combined heel block for both the tongue rails of the switch. Three-throw switches used in congested goods yards and at entry points to locomotive yards, where there is much limitation of space. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 7 Three-Throw Switch

8. Double Turnout A double turnou t or tandem is an improvement over a three-throw switch. In a double turnout, turnouts staggered and take off from the main line at two different places. The distance between the two sets of switches should be adequate to allow room for the usual throw of the point. Double turnouts mostly used in congested areas, particularly where traffic is heavy, so as to economize on space. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 8 Double Turnout

9. Diamond Crossing A diamond crossing is provided when two tracks of either the same gauge or of different gauges cross each other. It consists of two acute crossings (A and C) and two obtuse crossings (B and D). 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 9 Diamond Crossing

10. Single Slip and Double Slip In a diamond crossing, the tracks cross each other, but the trains from either track cannot change track. Slips are provided to allow vehicles to change track. The slip arrangement can be either single slip or double slip . 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 10 Single Slip and Double Slip

11. Scissors Crossover A scissors crossover enables transferring a vehicle from one track to another track and vice versa. It is provided where lack of space does not permit the provision of two separate crossovers. It consists of four pairs of switches, six acute crossings, two obtuse crossings, check rails, etc. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 11 Scissors Crossover

12. Triangle The  triangle  is a junction of a railway track, which is constructed for changing the direction of engines. They require a large area and therefore they are constructed where there is enough land available for their construction. This is mainly used for turning the faces of engines where the provision of the turntable is costly. https://youtu.be/d3xSZnyW1jc 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 12 Triangle

13. Advantages & Disadvantages Advantages Reduce infrastructure cost. Flexibility in routing. Minimal land acquisition. Disadvantages Limited capacity. Higher construction & maintences cost. Limited compatability . 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 13

14. CONCLUSION .

15. 7/13/2023 TRACK JUNCTIONS & SIMPLE TRACK LAYOUTS 15 THANK YOU