Railway Points and Crossing

Prof. Dr. Padma Bahadur Shahi

Points & Crossing

• To divert the train from one track to another

track some special arrangements are needed due

to the inside flanges on the wheel which can

move on a definite track. These special

arrangements are called points and crossings.

The points or switches provide the facility ofThe points or switches provide the facility of

diverting the vehicle and crossings provide gaps

in the rails to be crossed by the flange wheels. A

complete set of points and crossings is called a

turn out. Right hand turn-out and left hand turn

out is shown in figures below.

Some

– Turn out: A complete set of points and crossing along with lead rail is known as turn out. Details of a turn out are given in figure.

– Tongue rail: It is a tapered movable rail made of high carbon or manganese steel to withstand wear. It is attached at its thicker end to a running rail. Sometimes it is called switch rail.

– Stock Rail: It is running rail against which a tongue rail operates.– Switch: A pair of tongue and stock rails with necessary connections and

fittings form a switch. It is the device used to divert the rolling stock from one track to another track. It consists of a tongue rail and a stock rail. The one track to another track. It consists of a tongue rail and a stock rail. The tongue rail is supported on sliding plates and each pair of tongue rail is connected by a stretcher bar near the toe of the switch as in the figure. This arrangement keeps the movement of both tongue rails equal. A set of switch is known as point.

– Points: A pair of tongue rails with their stock rails is known as point. In other word a set of switches is known as point.

– Crossing: A crossing is a device introduced at the junction where two rails cross to permit the wheel flange of a railway vehicle to pass from one track to another track.

Right hand Turnout

Left Hand Turnout

Component Parts of a switch or Point:

1. A set of stock rail2. A pair of tongue rail3. A pair of heel block4. A number of slide chairs to support the tongue

railrail5. Two or more stretcher bars to connect tongue

rails6. A gauge tie plate to fix and ensure correct gauge

at points7. Guard or check rail

Component part of Crossings:

a) Two Rails: (Point and Splice rail ): Point rail ends at the nose while the splice rail joins a little behind the nose.

b) Two wing Rails: These are right and left hand wings rails. They converse to form a throat and diverge again on either side of the nose.

c) A pair of Check rails: To provide a path for the wheel flange c) A pair of Check rails: To provide a path for the wheel flange and guide them, a pair of check rails is provided.

Types of Crossings:

1. Acute angle crossings

2. Obtuse angle crossings

3. Square Crossings

Station & yards

• Station is a place on a railway line, where trains are stopped for passengers to entrain or detrain and an authority to proceed is given to the train.

• At some of the stations the movement of trains is also controlled. also controlled.

• A station should be located as near a village or town as possible with easy approach roads to facilitate the movement of passengers and goods as well.

• There should be provision of future extensions also.

Functions of railway station

• For exchange of passengers

• For exchange of goods

• For the control of train movements

• To facilitate the trains on a single line track to cross from opposite directionopposite direction

• To enable the following express trains to overtake the train ahead

• For taking fuels for locomotive

• For changing locomotive and running staff

• For attaching or detaching wagons and compartments

• For sorting of bogies to form new trains

Types of satations

1. Wayside station

2. Junction station

3. Terminal station

Wayside station

1. Wayside station: the station on which trains move only in two directions (upside & downside). a) Halt station: This is the simplest type of stopping

place. It may or may not have small room. There is place. It may or may not have small room. There is usually one platform. No permanent staff is kept at these halts. Ticket to passengers is issued either by travelling ticket examiner or travelling booking clerk. Sometimes tickets are issued by some contractors. They provide facility to nearby villages where there is low traffic volume. The main disadvantage of such halts is that many passengers travel without ticket.

Halt station

b. Flag station

• Flag station: a request stop, flag stop or whistle stopdescribes a stationat which trains stop only on an as-needed basis, that is, only if there are passengers to be picked up or dropped off. At request stops for which there are no passengers to be dropped off, trains need only slow are no passengers to be dropped off, trains need only slow in the vicinity of the platform — or, in some cases, pass it at speed — instead of coming to a complete stop at an empty platform. There are no arrangements to control the movements of trains and crossing facilities. These stations have buildings, staff and telegraph facilities.

c. Crossing station

These stations are provided with the facilities of crossing. These stations are provided at least one loop line to allow another train if one train is standing on the track. Generally the train which has to be stopped is taken on the loop line and the has to be stopped is taken on the loop line and the other through train is allowed to pass on the main line.

Crossing Station

Passenger Platform

Main Lines

Foot overbridge

Station Building

Loop

Goods Platform

Goods shed

Passenger Platform

Fig. Crossing station on double lines

2. Junction station

• The station where a branch line meets the main line as known as junctions. Following arrangements are essential for junction stations. – Facilities for the interchange of traffic between main

and branch lines.and branch lines.

– Facilities for repair and cleaning of the compartments

– Facilities of goods siding engine sheds turn table etc.

Junction station

General arrangement of railway station

1. Public Requirements:– Booking office

– Platform

– Drinking water

– Refreshment room

– Sanitary arrangement

– Enquiry office

– Station name board

– Waiting rooms

– Lighting arrangement

– Public telephone

Requirement of railway station

2. Traffic requirements– Machines for dating tickets

– Weighing machine

– Controlling and recording the movement of trains

– Siding to cross or overtake trains

– Sidings for good traffic

– Platform for loading, unloading & storing of goods

– Sitting arrangement for the staff of traffic department etc.

Requirement of railway station

3. Locomotive requirements:– Water column

– Fuel store and supply

– Cleaning & examining of locomotives

– Inspection of vehicles & locomotives

– Turn table for changing direction of locomotives

– Residential accommodation, rest waiting of railway staff

Requirements of railway stations

4. In General:– Suitable roads to the station

– Clock for accurate time

– Availabilities of coolies of the platform

Platforms

1. Passenger Platform • It is the place from where the passengers to

entrain or detrain. It is a loading space. The length of platform for all gauges should not be less than 180m. Generally about 305 m length of less than 180m. Generally about 305 m length of a BG railway platform is desirable. The edge of the platform from the center of the nearest track is kept 1.7 m away for BG, 1.39 m for MG and 1.2 for NG.

• Passenger platform

Passenger platforms

• Minimum length should not be less than 180m

• Minimum width should not be less than 3.67m & should be paved fully

• Platform should be covered at least for the length of 60m

• End of high level platform should be in the form of ramp • End of high level platform should be in the form of ramp the slope of 1:6

• Adequate lighting should be arranged for night

• Adequate drinking water

• The slope in its width should be 1 in 30

• The top width of masonry wall should be about 46 cm

• There is different level (height) of platforms:– Rail level platform: the height of such platform is

equal to the height of the rail

– Low level platform: the height of such platform should be kept about 45 cm above rail levelshould be kept about 45 cm above rail level

– High level platform: the height is kept about 76 to 85 cm above the rail level.

Goods platforms

• To facilitate the goods handling, generally height of goods platform is kept up to the floor level of the wagon. Essentials of goods platform:– Weighing arrangement

– Goods shed– Goods shed

– Proper drainage facility

– Facility for direct access from goods platform to goods sidings and to marshalling yards

Yards

• A yard is a system of railway tracks laid within definite limits of various purposes such as sorting of vehicles, making up trains etc.

• Yards are also used to control the movements by prescribed rules, regulations and signals. There prescribed rules, regulations and signals. There are four types of Yards:– Passenger Yards

– Goods Yard

– Marshalling Yards

– Locomotive yards

Passenger yards:

• the main function of the passenger yards is to provide all facilities for their safe movements of passengers. Following facilities should be there in passenger yard:

–Booking office–Booking office

– Parking space

– Enquiry office

– Signal for train receptions & departures

– Platform and sidings

Goods yards:

• requirements of goods yard:– Approach road

– Loop lines

– Loading & unloading platforms

– Space for goods sorting

– Cart weighing machine

– Cranes for very heavy goods– Cranes for very heavy goods

– Booking office

Marshalling yards:

• Is the space where goods wagons received from different centers are sorted out and placed in order to be detached at different stations. Thus marshalling yards are distributing centers.

• In short, marshalling yard is the center where goods wagons are sorted out and isolated wagons are combined to form a train load. Design consideration for marshalling yards:

– shunt ing operations should not be disturbed by the regular trains.

– Marshalling yard should be kept parallel to the running lines

– Movement of trains in only one direction is desirable

– Repair facilities for provided

Lay out of Marshalling Yards:

• The ideal layout of marshalling yard consists of following:– Reception siding

– Sorting siding

– Departure siding– Departure siding

Locomotive yards:

• Following facilities must be provided in this group:

• Sufficient number of tracks : Engine shed; ash pit; inspection; repair shed; turn table

• Loco yards should be situated near the passenger and goods yardsyards

• Water column

• Hydraulic jack

• Overhead tank and Loco well

Loops and Sidings

• Loops: when a branch line from a main line meets or terminates at the same main line, this arrangement is called as loops. Loops can be sub-divided into three groups:

– Split turn out: it is not suitable for fast through trains.

– Trailing turn out: A fast through train has to reduce speed slightly while crossing over a reverse curve.

– Straight and loop: For the fast through trains it is suitable as there is – Straight and loop: For the fast through trains it is suitable as there is no need reducing speed.

Sidings:

• When a branch line from a main line or a loop line terminates at a dead end with buffer stop, is called sidings. Function of siding is to provide temporary storage of wagons. There are four types of siding:types of siding:

• Trap sidings: the goods sidings are separated from main lines by a trap siding

• shunting sidings:

• Catch sidings: these are provided in hilly tracks

• Private and assisted sidings.

Staff quarters

• Residential quarters for the staff are provided on the station. The minimum clear distance from the center of the existing track to the boundary of quarters should be 8 meters. The proposed site should not interfere with the future expansion of should not interfere with the future expansion of the station and should be provided in three years.