turnout overview

1. Signalling system of railway
• As we mentioned before in the
previous video there are three
subsystems of the railway system ,
which are Signalling system,
Telecommunication system and
rolling stock system.
• The main subsystem of three
subsystems is the signalling system
• Signalling system is composed of
wayside or trackside elements and
indoor elements
• Now we’ll start with the wayside or
trackside elements
• The most critical and dangerous
element is the Turnout
• What is the turnout ?,and what are
the main components of turnout?

2. • Let's start with turnout terminology
A turnout is an assembly of rails, movable points, and a frog,
which effect the tangential branching of tracks and allows trains or
vehicles to run over one track or another
• The fouling point
Is the limit of occupation of the converging tracks.

3. • The points may be operated manually or by a point or switch
machine. Point or switch machines are either electric motor drives or
electrically controlled pneumatic cylinder drives.
• Movements on a turnout where the points face approaching traffic
are called ‘facing point movements’ whereas movements in which the
frog faces approaching traffic are called ‘trailing point movements’

4. • Crossing
A crossing is an assembly of rails that effects two tracks to cross at
grade, The inner part of a crossing is called a ‘diamond
• Derailers
are trackside devices that are used to protect train movements against
unattended movements of vehicles on converging tracks. An unsafe
movement will be derailed before it could join the protected route. In
the protecting position, a derailing piece is raised over one rail. Like
points, derailers can be hand or power operated.

5. Turnout view See you in the coming video