What are points and crossing in railway? what is turnout in railway? what are pointe or switches in railway

Last updated on May 15th, 2024 at 07:42 am

The arrangements by which different route either parallel or diverging from the first track are connected to facilitate the diversion of trains from one track to another track without any obstruction are known as points and crossing in railway.

The function of points is to facilitate the diversion of trains from one railway track to another track Whereas, the function of crossing is to provide gaps between the rails to be crossed so that the wheel flanges can pass through these gaps without any obstruction.

The necessity of points and crossing: The wheels of rolling stock in railway are provided with flanges on the inner side of rails so as to prevent the lateral movement of trains and to make them to run on rails in a well-defined track.

The flanges thus cause obstruction when the train are to be diverted from one railway track to another track. therefore, the provisions of points and crossing is necessary to facilitate the diversion of trains from one railway to another, either parallel or slightly diverging from the first track.

Functions

• To receive the trains approaching to the railway stations at the allotted platforms
• To enable the dispatched train at any railway station to occupy the specified track which leads to the destination station.
• To facilitate shunting and marshaling of trains from and to washing lines etc.

what is turnout in railway? What are the various component parts of a turnout and their functions?

Turnout in railway is an arrangement of points and crossing with lead rails by which trains may be diverted from one track to another moving in the facing direction.

A turnout is left-handed as the train taking the turnout in the facing direction is diverted to the left or right of the mainline.

Component Parts

• A pair of tongue rails: the tongue rails along with the stocks rails in a turnout form a pair of points or switches. The tongue rails facilitate the diversion of a train from the main track to a branch track.
• A pair of stock rails: they are the main rails to which the tongue rails fits closely. The stock rail help in smooth working of tongue rails.
• Two check rails: Check rails are provided adjacent to the lead rails, one in main track and another in-branch track. These rails check the tendency of wheels to climbs over the crossing.
• Four lead rails: outer straight lead rail, outer curve lead rail, inner straight lead, and inner curve lead rails provided in a turnout. The function of these rails is to leads the track from the heel of switches to the toe of crossing.
• A vee crossing: A Vee crossing is formed by two wings rails, a point rail, and a splice rail. It provides gaps between the rails so that wheel flanges pass through them without any obstruction.
• Slide chairs: It is provided to support the tongue rails throughout their length and to allow lateral movement for changing of points.
• Stretcher bar: it connects toes of both the tongue rails so that each tongue rail moves through the same distance white changing the pointe.
• A pair of heel blocks: these keep the heel ends of both the tongue rails at a fixed distance from their respective stock rails.
• Switch tie plate or gauge tie chair: The function of the switch tie plate is to hold the track rigidly to the definite gauge at the toe of switches. These are provided below the slide chairs.
• Parts for operating points- rods cranks lever etc.
• Locking system which includes locking box, lock bar plunger bar, etc.

A pair of tongue rails: the tongue rails along with the stocks rails in a turnout form a pair of points or switches. The tongue rails facilitate the diversion of a train from the main track to a branch track.

A pair of stock rails: they are the main rails to which the tongue rails fit closely. The stock rail help in the smooth working of tongue rails.

Two check rails: Check rails are provided adjacent to the lead rails, one in the main track and another in-branch track. These rails check the tendency of wheels to climbs over the crossing.

Four lead rails: outer straight lead rail, outer curve lead rail, inner straight lead, and inner curve lead rails provided in a turnout. The function of these rails is to leads the track from heel of switches to the toe of crossing.

A vee crossing: A Vee crossing is formed by two wings rails, a point rail, and a splice provide gaps between the rails so that wheel flanges pass through them without rail. any obstruction.

Slide chairs: It is provided to support the tongue rails throughout their length and to allow lateral movement for changing of points.

Stretcher bar: it connects toes of both the tongue rails so that each tongue rail moves through the same distance white changing the points.

A pair of heet blocks: these keep the heel ends of both the tongue rails at a fixed distance from their respectively stock rails.

Switch tie plate or gauge tle chalr: The function of switch tie plate is to hold the track rigidly to the definite gauge at the toe of switches. These are provided below the slide chairs.

Points and crossing | Indian railway | civil engineering department | how to change train track

what are pointe or switches in railway? What are their components parts? What are their different?

A pointe or switches in railway consist of a stock rail and a tongue rail. Each set of points consists of two switches, ope L/H, and one RH. In a switch, tongue rail is movable and is tapered to fit properly ağainst its respectively its respective stock rail.

Following are the component parts of points:

a) A pair of stock rails

b) A pair of stock rails
c) Switch tie plate
d) Heel blocks
e) Stretcher bar
f)Stops or studs
g) Slide chairs.
h) Switch anchors

Types

a) Stub switch
b) Split switch

Stub Switch: In this type of switch, no separate tongue rail is provided and some portion of rails of the track is placed on sliding chairs to move from side to side. It is an old type of switch and is structurally very weak. These switches are not in use these days.

Split Switch: A split switch consist of tongue rail and a stock rail with fastening. This type of switch provides more lateral rigidity to the turnout. These switches are mostly in use.

Component

A vee piece
A point rail
A splice rail
Two check rails
Two wings rails
Heel block at throat, nose, and heel of crossing
Chairs at crossing, at toe, and at heel.