Railway engineering By T.Ravi Prakash/Kongu Engineering College

RAILWAYS
By,
T.Ravi prakash
Assistant Professor
Kongu Engineering
College,Perundurai

“Transportation is regarded as an index of
economic, social and commercial progress of
the country”.
Modes of Transport
• Land transport
• Water transport
• Air transport
Two major means of land transport are Roads
and railways.
By,T.Ravi Prakash,KEC

Advantages of Railways
Political Advantages
• Railway have joined people of different castes,
religions customs and traditions.
• With adequate network of railway central
administration has become easy and effective
• Role of railway during emergencies in mobilising
troops and war equipment has been very significant.
• Railway have helped in mass migration of people.

Social Advantages
• Feeling of isolation has been removed from the
inhabitants of Indian villages.
• The social outlook of the masses has been
broadened through railway journeys.
• Railway has made it easier to reach religious
importance
• Provide safe and convenient mode of transport for
the country

Economic advantages
• Mobility of people has increased.
• Transport food and clothes during famines.
• Transport raw material to the industries
• Provide employment to millions of people.
• Land values increased due to industrial
development.
• Price stabilisation is possible.

Techno-economic advantages
Cost saving in transportation of long haul bulk traffic.
Energy efficient (1/7 fuel used as compared to road
sector)
Environment friendliness
Higher Safety (fatal accidents 1/10 of road sector in
India)

Features Rail Transport RoadTransport
Tractive resistance The movementof steel wheels on steel rails has
basic advantage of low rolling resistance.This
reduceshaulage costs because of low tractive
resistance.
The tractive resistance of a pneumatictyre
on metalled roads is almost five times
compared to that of wheel on rails.
Right of entry A railway track is defined on two rails and is
within protected limits.Trains work as per a
prescribed schedule and no other vehicle has the
right of entry except at specified level crossings.
Roads, though having well-defined limits,can
be used by any vehicular traffic and even by
pedestriansthey are open to all.
Cost analysis Owing to the heavy infrastructure,the initial as
well as maintenance cost of a railway line is high.
The cost of construction and maintenance of
roads is comparativelycheaper.
Gradients and
curves
The gradients of railway tracks are flatter
(normally not more than 1 in 100) and curvesare
limited up to only 100
on broad gauge.
Roads are constructed normally with steeper
gradients of up to 1 in 30 and relatively much
sharper curves.
Flexibility of
movement
Due to the defined routes and facilities required
for the reception and dispatch of trains,railway
can be used only between fixed points.
Roads transports have much more flexibility
in movementand can provide door to door
sevices.
Environmental
pollution
Railway has minimum adverse effects on the
environment.
Road transport creates comparatively
greater pollution than the railways.
Organizationand
control
Railways are governmentundertakings,with their
own organization.
Barring member state governmenttransport,
road transport is managed by private sector.
Suitability Railways are best suited for carrying heavy goods
and large numberof passengers over long
distances.
Road transport is best suited for carrying
lighter goods and smaller number of
passengers over short distances.

Indian Railway

History of Indian Railway
First Indian Railway line was
opened on 16th April 1853.

• The first train consisting of
one steam engine and four
coaches , traversed a stretch
of 21-miles between
Mumbai(Bombay) and Thane.
• Indian Railway has a glorious
past of more than150 years
serving the nation.

Development of Indian Railway(IR)
• In 19 century before the introduction of railways, India
was a country with extremely poor means of
communications.
• In1844 the first proposals for the construction of
railway on India was submitted to East India Company
• In 1853 first railway line between Bombay to Thana was
opened.
• In 1905 Railway Board was established with one
president and two members.
• In 1939 total route kilometrage of India was 65,850
kms.

First Five Year Plan (1951-1956)
• out of total plan expenditure of Rs. 2378
crores the railway were allotted only 257 crores
• Rehabilitation of railway assets was main
objective.
• Industries boosted up their locomotive
production during these years
• Considerably helped India in achieving self
sufficiency

Second five year plan (1956-1961)
• Second five year plan had a provision of Rs.
896 crores for the development of Indian
railways out of total expenditure of Rs. 4800
crores.
• Many new lines were opened, and new
locomotives and coaches were placed on
line.
• Considerable progress was made in
electrification of railway.

Third five year plan (1961-1966)
• Second five year plan had a provision of Rs.
1470 crores for the development of Indian
railways out of total expenditure of Rs. 7500
crores.
• Plan provided acquisition of 2070
locomotives, 157133 wagons and 7879
coaching vehicles.
• Made a provision for electrification about
2400 route kms.
• A length of 2400 kms new lines was also
constructed.

Fourth five year plan (1969-1974)
• With objective of modernisationof railway.
• Improving the operational efficiency of the
system by more intense utilisation.
Fifth five year plan (1974-1978)
Development of rapid transport system in
metropolitan cities.
A sum of 2200 crores were allotted out of total
39300 crores.

Sixth five year plan (1980-1985)
• Main objective was the limited resources of
the railways should be used for rehabilitation
of assets.
• The stress was to use existing resources in
best possible manner for getting high
operating efficiency.

Seventh five year plan (1985-1990)
• Provided for an outlay of Rs. 12334 crores.
• Augmentation of capacity for manufacturing
of passenger coaches, electric multiple units
and electric locomotives.
• Introduction of computer based freight
operation information system and
computerisation of passenger reservation.

Eighth five year plan (1992-1997)
Provided an outlay of 27202 crores.
Emphasis on modernisationof system to reduce
operating cost and improve reliability.
Convert a length of 6000 km of M.G and N.G
tracks to broad gauge.

Ninth five year plan (1997-2002)
Outlay of 45413 crore (14.1% of total plan)
Generation of rail transport capacity to handle
increased freight and passenger traffic.
Completion of replacement, rehabilitation and
renewal of over aged assets.
To continue with the policy of Uni-guage
throughout the country.
Introduction of 4000 H.P. diesel locomotives and
6000 H.P. electric locomotives.

Tenth five year plan (2002- 2007)
 In 2002, Jan Shatabdi trains introduced
 In 2003, Indian raiway has 16 Zones and 67
divisions
 Outlay of 840,030 million

Eleventh five year plan (2007- 2012)
 Outlay of RS 2,332,890 million out of Rs
41,185,310 million
 Strengthening of high density network and
improving rail safety and increase rail traffic

Organization of Indian Railway (IR)
• Biggest public undertaking
• Capital-at-charge of about Rs 560,000 million.
• The executive authority in connection with
the administrationof railway vests with
Central Government and the same has been
delegated to Railway Board as per Indian
Railway Act 1890 and Indian Tramway act of
1816.

Railway Board (RB)
• RB exercise all powers of central government
in respect of regulation, construction,
maintenance, and operation of railway.
• RB consists of a chairman, a financial
commissioner, and five other functional
members.
• Chairman reports to Minister for railway.
• The member of RB are separately in charge of
matters relating to staff, civil, electrical,
mechanical and traffic.

• Presently IR is divided into 16 zones.
• Each Zonal railway is administered by a general
manager(GM) assisted by additional GM and
HOD of different disciplines, namely, civil
engineering, mechanical, operating, commercial,
accounts, security, signals and
telecommunications, electrical, personnel,
medical, etc.
• Zonal railway is further divided into 3 to 6
divisions.
• Each division work under control of Divisional
railway manager (DRM).

 There are divisional officers in charge of each
discipline namely, divisional superintending engineer
(DSE) or Divisional Engineer for civil engineering etc.
 DSE is normally the head of the unit in the division.
 Under each DSE, there are 2 to 3 divisional engineers
(DENs)
 Each DEN is assisted by 2 to 3 assistant engineers
(AENs).
 An AEN has about 400 integrated track km under his
charge.
 The AENs are assisted by permanent way inspectors.

Indian Railway Facts
• The total distance covered by the 14,300 trains on the
Indian Railways everyday, equals three & half times the
distance to moon
• The first train on Indian soil ran between Bombay and
Thane on the 16th of April 1853
• IR has about 67,312 route kms. of track (28,000
electric)
• IR employs about 1.55 million people It carries over 13
million passengers & 1.3 million tones of freight
everyday
• It runs about 14,300 trains daily
• IR has about 7,000 railway stations
• The longest platform in the world is at Kharagpur and is
2,733 ft. in length

• Nehru Setu on Sone River is the longest Railway bridge
• 42 Railway companies operated in the country before
independence
• Electric Locomotives are manufactured at Chittaranjan
Locomotive Works, Chittaranjan Coaches are
manufactured at ICF/Chennai, RCF/Kapurthala and
BEML/Bangaluru
• The national Rail Museum at New Delhi was set-up in
1977
• People Employed in Indian Railway are about 1.6 million
• Stations across State Lines are Navapur (Maharashtra and
Gujarat) and Bhawani Mandi (Madhya Pradesh and
Rajasthan)
• Classes of travel on Indian Railway: Ist AC, 2nd AC, 3rd AC,
AC Chair Car IInd sleeper & IInd ordinary
• Railway Station with all the Three Gauges is Siliguri
Railway Station

It carries 1.4 crore passengers and 16
lakh tonnes of goods every day.

It is fuel efficient system.
7000 stations & about 500 computerized
passenger reservation system.

Speed ofTrains
Gatimaan Express 160kmph
Shatabdi max 140kmph.
Rajdhani max 130kmph.
Others max 110kmph.

Important Technical Terms
There are many important technical terms
concerning to Railways, but a few terms which are
of immediate concern are only discussed bellow:-
1. Railway track:-A track formed of rails of iron or
steel along which trains are driven is known as
railway track.
In general, the term railway also includes all
lines of rails, sidings or branches.
2. Rolling stock:- The locomotives, passenger
coaches and goods wagons which roll or run on
railway tracks constitute rolling stock.

3. Locomotive:-The mechanical device which
transfers chemical energy of fuel into
mechanical energy in the form of motion is
called locomotive.
The fuel used in the locomotives may be in
the form of water and coal, diesel or electricity.
4. Wagons :- The goods compartments are called
wagons. This term applies only to good stock.
5. Coaches or vehicles :- The passenger
compartments are called coaches or vehicles.
This term applies only to coaching stock.

6. Siding: when a branch starting from main
line terminates at the dead end with a buffer
stop is known as siding.
7. Ballast: is the granular material packed
under and around the sleepers to transfer
the loads from the sleepers to subgrade.

TYPES OF GAUGES PREVALENT IN INDIA
The different gauges prevalent in India are of the following
these types :-
1-Broad Gauge(BG) 1676mm(5’6”)
2-Standard Gauge(SG) 1435mm
3-Metre Gauge(MG) 1000mm
4-Narrow Gauge(NG) 762mm(2’6”)
5-Light Gauge 610mm
In India, efforts are being made to convert all N.G. and
M.G. lines to B.G. lines on important sections as and
when funds are available.

RAIL GAUGE
The gauge of a railway track is defined as the clear
minimum perpendicular distance between the inner
faces of the two rails.

RailwayTrack or
Permanent Way
Combination of rails, fitted on sleepers and
resting on ballast and subgrade is
called the railway track or permanent way.

Track Cross-section

 Rails are fixed to sleepers by different types of
fixtures and fastenings (chairs, bearing plates,
fish plates, fish bolts, spikes etc.).
 Sleepers hold the rails in proper position with
respect to their proper tilt, gauge and level
and transmit the load from rails to the ballast.
These sleepers are suitably spaced, packed
and boxed (the process of filling the ballast
around the sleepers) with ballast. The typical
length of a BG sleeper is 2.7 m.
 Ballast is a high quality crushed stone with
desired specifications placed directly below
the sleeper.

 Ballast distributes the load over the formation
and holds the sleepers in position and also
functions as drainage layer.
 Formation is the compacted and prepared
subgrade which is the part of embankment or
cutting
 Natural subgrade is the soil in the natural
ground on which the track rests.
 Ballast cushion: The depth of ballast below the
bottom of the sleeper, normally measured
under rail seat is termed as ballast cushion.

• Ballast shoulder: Ballast provided beyond the
sleeper edge is termed as ballast shoulder
(shown as C in Fig., typically 0.35 m in a BG
track)
• Ballast Base: It is the bottom width of ballast-
bed (typically 4.4 m in a BG track).
• Formation width: It is the top width of
embankment or bottgom width of cutting
(Typically 6.1 m in a BG track)
• Cess width: Width of formation beyond the
toe of ballast is termed as cess width.

Conventional track structure

REQUIREMENTS OF AN IDEAL PERMANENT WAY
The following are the principal requirementsof an
ideal permanent way or of a good railway
track :-
i. The gauge of the permanent way should be
correct and uniform.
ii. The rail should be in proper level in straight
portion. Proper amount of super elevation
should be provided to the outer rail above the
inner rail on curved portion of the track.
iii. The permanent way should be sufficiently
strong against lateral forces.

iv. The curves, provided in the track, should be
properly designed.
v. An even and uniform gradient should be
provided through out the length of the
track.
vi. The tractive resistance of the track should
be minimum.
vii. The design of the permanent way should be
such that the load of the train is uniformly
distributed on both the rails so as to prevent
unequal settlement of the track.
viii. All the componentsparts such as rails,
sleepers, ballast, fixtures and fastenings,
etc. should satisfy the design requirements.

ix. All the points and crossings, laid in the
permanent way, should be properly designed
and carefully constructed.
x. It should be provided with proper drainage
facilities so as to drain off the rain water
quickly away from the track.
xi. It should be provided with safe and strong
bridges coming in the alignment of the track.
xii. It should be so constructed that repairs and
renewals of any of its portion can be carried
out without any difficulty.

Length of Indian Railway Track
• Route kilometer:this is the route length of
railway between origins and destinations
• Running track kilometer: This is the length of
running track on a route. On a route with
double track, the running track kilometer is
about twice the route kilometer.
• Total track kilometer is the physical length of
track available. This length is arrived at after
giving due weightage for the length of track
on track junctions, sidings, etc., and adding it
to the running track kilometer.

Length of Indian Railway Track
Type of Track Length*, km
Broad Gauge (BG) 60,000
Meter Gauge (MG) 4000
Narrow Gauge (NG) > 2000

Selection of Guages
1.Cost of construction
 There is marginal increase in the cost of
earthwork, rails, sleepers, ballast, and other
track items with gauge.
 The cost of station buildings, platforms, signals,
bridges, tunnels and culverts etc., is same more
or less for all gauges.
 There is little proportional in the acquisition of
land.
 The cost of rolling stock is independent of the
guage used for same volume of traffic.

2.Volume and nature of traffic.
For heavier loads and high speed, the wider guage
are required because subsequently the operating cost
per tonne-km is less for higher carrying capacity.
3.Speedof movement
Speed is a function of dia. of wheel, which in turn
limited by the guage. (wheel diameter = 0.75 x Gauge).
4.Developmentof areas
Narrow guages can be used for thinly populated
area by joining under developed area with developed or
urbanised area.
5.Physical features of the country
Use of narrow guage is warranted in hilly regions
where broad and meter guage are not possible due
steep gradients and sharp curves.

RAILS
The high carbon rolled steel sections, which are
laid end-to-end, in two parallel lines over sleepers
to provide continuous and leveled surface for the
trains to move and for carrying axle loads of the
rolling stock are called rails.
`

• Rail transmit loads to the sleepers and
consequently reduce pressure on ballast and
formation below.
Composition of rail steel
For ordinary rails
Carbon (C) - 0.55 to 0.68 percent
Manganese (Mn) - 0.65 to 0.9 percent
Silicon (Si) - 0.05 to 0.3 percent
Sulphur (S) – 0.05 percent or below
Phosphorus (P) – 0.06 percent or below

For rails at points and crossings
Carbon (C) - 0.5 to 0.6 percent
Manganese (Mn) - 0.95 to 1.25 percent
Silicon (Si) - 0.05 to 0.2 percent
Sulphur (S) – 0.06 percent or below
Phosphorus (P) – 0.06 percent or below

Functions of the rails:
 To provide continuous and level surface for the
movement of trains with minimum friction with
steel wheels of the rolling stock;
 Provide strength, durability and lateral guidance
to the track;
 Transmit the axle loads to sleepers which transfer
the same load to the underlying ballast and
formation;
 Bear the stresses developed due to heavy vertical
loads, breaking forces and temperature variance.

Types of Rails
1- Double Headed Rail.
2- Bull Headed Rail.
3- Flat Footed Rail.

RAILS
1. Double Headed Rails:
 This type of rail consists of three parts – upper
table, web, and lower table;
 Both the upper and lower tables were identical;
 They were introduced with the hope of doubling
the life of rails;
 When the upper table was worn out, the rails can
be reversedin the chair and thus, the lower table
can be brought into use;
By, T.Ravi Prakash,KEC

RAILS
However,this idea soon turned out to be wrong
because it was observed that long contact with
chairs made the surface of lower table very rough
and smooth running of trains was then
impossible.
Thus, these rails are nowadays practically out of
use;

RAILS
2. Bull Headed Rails:
 These rails consist of head, web and foot and are
made of steel;
 The head is larger than the foot and the foot is
designed only to properly hold the wooden keys
with which the rails are secured to chairs;

RAILS
The two cast-iron chairs are required per each
sleeper when these rails are adopted.
These rails are extensively used in England and in
some parts of Europe.

RAILS
3. Flat-footedRails:
In this type of rail, the foot is spread out to form a
base;
This form of rail was invented by Charles Vignoles
in 1836 and hence, these rails are sometimes
known as Vignoles rails;
At present, about 90% of the railway track in the
world is laid with this form of rails.

RAILS
Advantages:
i. Chairs: No chairs are required in this form of
rails. The foot of the rail is directly spiked to the
sleepers.This fact makes them economical.
ii. Stiffness: This form of rail is stiffer, both
vertically and laterally than the bull-headed rail
of equal weight. Especially on curves, the lateral
stiffness of rails is very important.
iii. Kinks: This form of rail is less liable to develop
kinks and it maintains a more regular top surface
than the bull-headed rails.By, T.Ravi Prakash,KEC

Standard rail sections & Rail length

Corrugated or Roaring Rails
In certain places, head of rails are found to
be corrugated rather than smooth and
straight, when the vehicles pass over such
rails, a roaring sound is created which is
intense enough to be unpleasant.

Hogged Rails
Due to battering action of wheels over the end of the rails, the
rails get bent down and get deflected at the ends. These rails are
called hogged rails.
Measures taken to rectify the hogged rails are:
1. Cropping
2. Replacing
3. Welding
4. Dehogging

Reason of Hogging!
https://www.youtube.com/watch?v=9njqDgjIcWQ

Kinks In Rails
When the ends of adjoining rails move slightly out of position,
“shoulders” or “kinks” are formed.
Measures taken to rectify kinks in rails:
1. By correcting alignment at joints and at curved locations.
2. Proper packing of joints.
3. Proper maintenance of the track periodically in repect of
cross levels, gauge,alignment, welding of worn out portions
etc.

Buckling of Rails
Buckling means the track has gone out of its original position or
alignment due to prevention of expansion of rails in hot weather
on account of temperature variations.

Damaged Rails
These are the rails which should be removed on
account of their becoming unsafe for a railway
track.

Rail Features
 Crushed Heads
 Square or Angular Break
 Split Heads
 SplitWeb
 Horizontal Fissures
 Transverse Fissures
 Flowing Metal in Heads
 Horizontal Cracks

Crushed Head

Split Heads

Horizontal and Transverse Fissures

Flowing Metal in Heads

Rail Joints
 Supported Rail Joint
 Suspended Rail Joint
 Bridge Joint
 Base Joint
 Welded Rail Joint
 Staggered or Broken Joint
 Square or Even Joint
 Compromise Joint
 Insulated Joint
 Expansion Joint`

Rail Joint

Insulated Joint

Expansion Joint

Creep of Rails
Creep is defined as the longitudinal movement
of the rail with respect to the sleepers.

Theories of creep
1. Wave action or wave theory:
Wave motion is set up by moving loads of wheels.
The vertical reverse curve ABC is formed in the
rail ahead of wheels, resulting from the rail
deflection under the load.

2. Drag (or) Dragging theory:
✓ Backward thrust on driving wheels of locomotive of train
push the rail off track backward.
✓ Mean while other wheel of locomotive and vehicles push
the rail in the direction of travel.
✓ Since drag effect is more as explained in Wave Action Theory
resultant creep of rails in forward direction.
3.. Percussion Theory:
This theory states that the creep is due to impact of wheels at
the rail end ahead at joints. Hence as and when wheel leave
the trailing rail and strike the facing rail end at each joint it
pushes the rail in forward direction resulting in creep.

4. Starting, accelerating, Slowing down (or)
stopping of a train:
✓Backward thrust of the engine driving wheels
push the rails backward when a train is
starting and accelerating.
✓When slowing down or stop the vehicle
braking forces are push the rail forward.

5. UnbalancedTraffic:
a) Single line:
✓ Heavy equal loads pass in both direction, the
creep is balanced. If not creep takes place in
the heavy load direction.
b) Double line:
✓ Since loads are in unidirectional creep occurs
in both directions.

Factors effecting the magnitude & direction of
creep.
 Alignment of track: Creep is more on curves than
on tangent tracks.
 Grade of track: More in case of steep curves,
particularly while train moving downwardwith
heavy loads.
 Type of rails: older rail have more tendency than
new one.
 Direction of heaviest traffic: In heavier load
moving direction occurs more creep.

Effects of creep
• Most serious effect of creep is being buckling of track.
• Common effects of creep:
• Sleepers move out of square and out of position, affects
the gauge and alignment of track. As sleepers move
surface is disturbed results uncomfortable riding.
• When joints are opened out beyond the permissible
stress in bolts and fish plates tendency to occurrence of
failure in them.
• Rails ends also battered due to occurrence of excessive
gaps at joints. While at other places , joints are jammed
and prevent required expansion due to thermal
stresses.

Contd..
• Points and crossings get distorted, its too
difficult to set them to correct gauge and
alignment. Movement of switches is made
difficult and interlocking is thrown out of gear.

• Its difficult to fix the removed rail at proper
position during repair works since the time gap
becomes too short or too long due to creep.
• Smashing of fish plates, bolts, bending of bars,
kinks at joints of rails and forging of ballast
ahead, common effects of creep.
• If creep is not prevented in time it will results
derailment.

Remedies of creep:
1. Pulling back the rails:
✓ pull back the rail to its original position. By means of crow
bars and hooks provided through the fish bolts wholes of
rails
✓ By considering the position of joints relative to sleepers
and both rails should be in respective position.
2. Provision of anchors or anticreepers:
✓ By use of anchors and sufficient crib ballast.
✓ For creep 7.5 cm-15 cm 4 anchors per rail
✓ For creep 22.5 to 25 cm 6 anchors.
3. Use of steel sleepers:
✓ Sleepers should be made up of good material with proper
fitting. Sleepers should provide good grip with ballast to
resist the movement of sleepers. Increase in no. of
sleepers.

Coning of Wheels
 The wheels of locomotive are not flat but
sloped or coned at a slope of 1 in 20.
 The distance between inside edges of wheel
flanges (B) is generally kept less than the
gauge (G). This results in a gap of 1 cm
between flange and running face of rail.

Coning of Wheel on Level-trackBy,T.Ravi Prakash,KEC

Theory of coning
Advantages of coning:
✓ Reduce the wear and tear of wheel flanges and rails.
✓ To provide possibility of lateral movement of the axle with its
wheels.
✓ To prevent the slipping of wheels.
Theory of coning:
✓ On level track, as soon as the axle moves towards one rail, the
dia of the wheel tread over the rail increases, while it
decreases over the other rail. This prevents the further
movement and axle get back to its original position.
✓ Due to rigidity of the wheel base either the wheel must slip by
an amount equal to the difference of length or the axle move
slightly outwards to provide a tread of longer diameter over
the outer rail and smaller diameter over the inner rail.

Theory of coning

If the tread dia. on both the rails is same then amount
of slip is:
Slip=θ (R₂-R₁)
Where, outer radius, R₂= R+(G/2)
R₁= R- (G/2)
G=Gauge
θ= angle at centre in radians.
Slip= θ×G
G=1.676 meters for B.G
Slip= (2πθ˚/360)×1.676
θ˚=angle at centre (degree)
Therefore, Slip = 0.029 m per degree of central angle

Track fittings and rail fastenings are used to keep the rails in
the proper position and to set the points and crossings
properly.
They link the rails endwise and fix the rails either on chairs
fixed to sleepers or directly on to the sleepers.
The important fittings commonly used are:
1. Fish plates
2. Spikes
3. Bolts
4. Chairs
5. Blocks
6. Keys
7. plates
Track Fittings and Fastenings

Track Fittings & Fastenings
 Fish plates
 Spikes
◦ Dog spikes
◦ Screw spikes
◦ Round spikes
◦ Standard spikes
◦ Elastic spikes
• Bolts
– Dog or Hook bolt
– Fish bolt
– Rag bolt
– Fang nut and bolt
• Keys
– Wooden key for C.I. Chair
– M.S. key and steel trough
sleepers
– Stuart’s key
– Morgan key
– Cotter and tie bars
• Chairs
– Cast steel chairs
– Mild steel and Cast Iron
Slide Chairs

Spikes
For holding the rails to the wooden
Sleepers various types of spikes are used.
Requirements of spikes:
Spikes should be strong enough to hold the rail in
position and it should have enough resistance against
motion to retain its original position.
The spikes should be deep for better holding power.
It should be easy in fixing and removal from the
sleepers.
The spikes should cheap in cost and it should capable
of maintaining the gauge.

Types of spikes
Dog spikes.
Screw spikes.
Round spikes.
Standard spikes.
Elastic spikes.

Dog Spike

Screw spikes

Round spikes:
The head shape is either cylindrical or hemi
spherical.
These are used for fixing chairs of B.H. rails to
wooden sleepers and also fixing slide chairs of
points and crossing.

1.Fish plate joint
2.Fasteners joint
3.Slide chaiars joint
4. Junction plate joint
5.Bearing plate joint
6.Chairs
Rail Joints

Fish plates: these are used in rail joints to maintain the
continuity of the rails and to allow expansion and
contraction.
Requirements of fish plates:
• Fish plates should maintain the correct alignment both
horizontally and vertically.
• They should support the underside of the rail and top of
the foot.
• Provide proper space for the expansion and contraction
• They should be made up of such a section to withstand
shocks and heavy stresses due to lateral and vertical B.M
Sections of fish plates:
Various sections have been designed to bear the stresses due
to lateral vertical bending.
Standard section is bone shaped

Fish Plate

Fish plates

FASTENERS JOINT

SLIDE CHAIARS JOINT

JUNCTION PLATE

Bolts
(i) Dog or hook bolt.
(ii) Fish bolts.
(iii) Fang nut bolts.

Chairs
(i) Cast iron chair (C.I chairs).
(ii) Slide chairs.

Blocks: when two rails run very close as in case of
check rails, etc. small blocks are inserted in
between the two rails and bolted to maintain the
required distance.
Bolts: used for fixing various track components in position.
Dog or hook bolt: when sleepers rest directly on
girder they are fastened to top flange top flange of
the girder by bolts called dog bolts.
Fish bolt: made up of medium or high carbon steel.
For a 44.7 kg rail, a bolt of 2.5 cm. dia. and 12.7
cm length is used. With each fish plate standard
practice is to use four bolts. Generally, a
projection of 6 mm of the shank is left out after
the nut is tightened.

Keys:
Keys are small tapered pieces of timber on steel to fix rails
to chairs on metal sleepers.
Morgan key:
This is about 18 cm long and tapered 1 in 32. these are suit
the C.I chair, plate sleepers and steel sleepers with the
rail.
The advantages of morgan keys are
• They can be used as left hand or right hand keys.
• They are light in weight due to double recess on either
side.
• They are versatile in nature.

Bearing plates:
Bearing plates are rectangular plates of mild steel or
cast iron used below F.F rails to distribute the load
on larger area of timber sleeper.
Advantages:
• To distribute the load coming on rails to the sleepers
over a larger area and to prevent skidding of the rail
in the soft wooden sleepers.
• Prevent the destruction of the sleeper due to
rubbing action of the rail.
• Adzing of sleeper can be avoided by bearing plates.

Bearing Plate

Sleepers
Sleepers are the transverse ties that are laid to
support the rails. They transmit wheel load from
the rails to the ballast.

Functions of sleepers:
▪ To hold the rails to correct gauge.
▪ To act an elastic medium between the
ballast and rail to absorb the blows and
vibrations due to moving loads.
▪ To distribute load from the rail to the
index area of ballast or to the girders in
case of bridges.
▪ To support rails - at proper level in
straight tracks
- at proper super
elevation on curveBy,T.Ravi Prakash,KEC

• Sleepers also provide longitudinaland lateral
stability of the permanent track on the whole.
Requirements of sleepers: an ideal sleeper
should possess the following characteristics.
• Sleeper should be economical i.e, minimum
initial and maintenance cost.
• Fitting of the sleepers should be easily
adjustable during maintenance operations.
Such as
✓Lifting
✓Packing,
✓Removal and replacements.

✓The weight of the sleeper should not be too
heavy or excessively light i.e. with moderate
weight they should be for ease of handling.
✓Design of sleepers should be such a way that the
gauge and alignment of track and levels of the
rails can easily adjusted and maintained.
✓The bearing area of sleepers below the rail seat
and over the ballast should be enough to resist
the crushing due to rail seat and crushing of
ballast under sleepers.
✓Design and spacing such a way to facilitate easy
removal and replacement of ballast.

• Sleepers should be capable of resisting shocks
and vibrations due to passage of heavy loads of
high speed trains.
• Sleepers design should be such a way they are
not damaged during packing process.
• Design should be strong enough so that they are
not pushed out easily due to the moving trains
especially in case of steel sleepers with rounded
ends.
• An ideal sleeper should be anti-sabotage and
anti-theft qualities.

Classification of sleepers
(i) Wooden sleeper
(ii) Metal sleeper
Cast iron sleeper
Steel sleeper
(iii) Concrete sleeper
Reinforced concrete
Sleeper (R.C.C)
Prestressed Concrete
Sleeper .

Wooden Sleepers
 Hard wood such as, sal and teak
 Soft wood such as, chir and deodar

 Classificationof sleepers.
1. Wooden sleepers:
✓ Wooden sleepers regarded to be best as they are fulfill all
the requirements of ideal sleeper.
✓ Life of timber sleepers depends on their ability to resist
wear, decay, attack by vermin, and quality of timber.
✓ Easily available ( Sal, teak, chir and deodar).
✓ Fittings to the wooden sleepers are few and simple in
design.
✓ Resist shock and vibrations.
✓ But it is difficult to maintain gauge in case of wooden
sleepers.
✓ Service life is minimum (12 to 15 years) and maintenance
cost is also high as compared to other sleepers.

2. Metal sleepers:
✓ These are either steel or cast iron, mostly cast
iron since it is less prone to corrosion.
Requirements of metal sleepers:
✓ They should be capable of the tensile and
compression stress due to the moving loads.
Cast iron sleepers:
a. Pot or bowl sleepers
b. Plate sleepers
c. Box sleepers
d. C.S.T 9(Central standard trial)sleepers
e. Rail free duplex sleepers

Metal Sleepers

Pots or bowl sleepers:
✓They consists of two bowls placed inverted on
the ballast.
✓Effective bearing area 0.232 sq.m is provided
under each rail support.
✓On top of the pot, a rail seat or chair is provided
to hold the F.F rail or B.H rail with cant of 1 in
20.
✓Weight of sleeper is 114 kg. it can be used on
curves, sharper than 4˚ on B.G.

Steel sleepers:
Various types of steel sleepers
1. Key type a) lugs or jaw pressed out of metal
b) with loose lugs or jaws
2. Clip bolt type
3. Saddle or spring type.
Features
 Fastening to the sleepers are less in numbers and
simple in nature.
 Gauge by use of steel sleepers can be easily adjusted
and maintained.
 Life of sleepers is much more than wooden sleepers.
 Cost is relatively more than wooden sleepers.

3. Concrete sleepers:
Two types of concrete sleepers
i. Reinforced concrete sleepers
ii. Pre-stressed concrete sleepers.
Concrete material is called as ideal sleeper due to
i. They made up of strong homogeneous material.
ii. Impervious to effect of moisture.
iii. Unaffected by the chemical effect of atmospheric
gases or sub soil salts.
iv. Easy to mould into required shapes to withstand
the stresses developed by moving loads.

Reinforced concrete sleeper: these are 2 types
1. Through type: in this type when concrete sleepers is
stressed, cracks on the tension side are inevitable.
Though these cracks are very small they tend to
enlarge with repetition of the impact loadings of fast
trains. This is the major reason for the failure of this
sleeper.
2. Composite tie type
Prestressed concrete sleepers:
drawbacks of previous one can be eliminated by this type of
sleepers,.
1. In this concrete is put under very high initial compression.
2. The max permissible compressive strength of 211 kg/cm2.
3. Max. cube crushing strength of concrete in the sleeper is
422 kg/cm2 at 28 days.
4. Pre-stressed wires are stressed to an initial stress of 8.82
kg/cm2.

Wooden sleepers
Reinforced concrete sleepers
Prestressed concrete structures Anchors

Concrete Sleepers

Metal Sleeper

Adzing of Sleepers:
In order to obtain an inward slope of 1 in 20 for the rail,
sleepers are adzed to form a table at this slope at the rail
seat.
This process is known as adzing of sleepers. Generally
adzing is done for wooden sleepers.
For smooth and comfortable journey accurate adzing is
required.
1 in 20
slope
1 in 20
slope

Sleeper Density
Sleeper density is the number of sleepers
Per rail length. It is specified as (M+x) or
(N+x), where M or N is the length of the
rail in meters and x is a number that varies
according to factors such as axle load,
speed,type & section of the rail etc.
It varies in India from M+4 to M+7 for main
tracks.

Ballast
Ballast is the granular material usually broken
stone or bricks single and kanker, gravel and
sand placed and packed and around the sleeper
to transmit Load from sleeper to formation
Layer.. Generally has a nominal size of 63mm
or 53mm. Can be used as a very coarse
drainage material.

Ballast
To provide structural support for
the track, holding it in good line
and surface
To distribute the load evenly to the
subballast and subgrade and thus
help to provide stability
Provide for drainage
Ballast in railroad terminology is durable granular material placed between
the crosstie and the sub ballast to hold the track in line and grade.
The primarypurposes of ballast are:

BALLAST
SUBBALLAST SUBGRADE
BALLAST SECTION

Types of Ballast
 Broken Stone
 Gravel or River Pebbles or Shingle
 Ashes or Cinders
 Sand
 Mooram
 Kankar
 Brick Ballast
 Blast Furnace Slag
 Selected Earth

Ballast material:
1. Broken stone:
✓ It is the best material for the ballast. Mostly stone
ballast is used in all important tracks.
✓ The best stone for ballast is a nonporous, hard and
angular. Igneous rocks such as hard trap, quartzite and
granite are good material and are used in large
quantities for high speed tracks in India.
✓ For stability , graded broken stone ballast is better than
ungraded one.
✓ The size of stone ballast should be 5 cm for wooden
sleepers and 4 cm for metal sleepers.

Broken stone:

3. Ashes or cinders:
Earlier this is available in large scale on railways since coal been
used in locomotives.
It can provide excellent properties since it is very porous in nature
and has good drainage property
It is very cheap and can be used in sidings but not in main lines as
it is very soft and gets reduced due the wheel load pressure
and make the track very dusty.
Due to its corrosive quality it corrodes the steel sleepers and foot
of the rail.
But in emergency such as floods ashes or cinders can be used for
the repairing formation or packing tracks.

It is a lime agglomerate. It can be used where stone is not available.
It can be used in road and railways as well.

8. Blast furnace slag:
It is a by-product in the manufacture of pig iron forms.
The material should be hard and with high density
and these are free from gas holes.
9. Selected earth

Size of ballast:
The broken stones either of too big size or too small size
are found unsuitable for railway ballast.
Size of ballast depends upon
▪ Type of sleepers
▪ Maintenance method
▪ Location of the track.
The size of the ballast used varies from 20mm to 50mm with
reasonable proportion of intermediate sizes. The exact size
of the ballast depends upon the type of sleepers.
▪ For wooden sleepers-51mm
▪ For steel sleepers-38mm
▪ For under switches,points and crossings-25.4mm

Points & Crossings
 Points and crossings provide flexibility of
movement by connecting one line to
another according to requirements.
 They also help for imposing restrictions over
turnouts which necessarily retard the
movements.
 From safety aspect, it is also important as
points and crossings are weak kinks or
points in the track and vehicles are
susceptible to derailments at these places.

Turnouts
 It’s the simplest combination of points and crossings which
enables one track either a branch line or a siding, to take
off from another track.
 Parts of a turnout:
◦ A pair of points or switches
◦ A pair of stockrails
◦ AVee crossing
◦ Two check rails
◦ Four lead rails
◦ Switch tie plate
◦ Studs or stops
◦ Bearing plates, slide chairs, stretcher bars etc.
◦ For operating the points – rods, cranks, levers etc.
◦ For locking system – locking box, lock bar, plunger bar etc.

POINT OF CROSSING
Point , crossing , turnout , cross-overs
and such related terms are arrangement
by which different routes either parallel
are connected and offered the means
for terms to move from one route to
another route is called POINT OF
CROSSING .

1. A pair of stock rail.
2. A Pair of tongue rail.
3. Heel Block.
4. Stretcher bar.
5. Slide Chair.
COMPONENTS OF SWITCH

A pair of stock rail

A Pair of tongue rail

Heel Block

Stretcher bar

POINT OF SWITCH
A SWITCH Consist of stock
rail and tongue rail.
A point is consist of left hand And
right hand switch

Slide Chair

Types of Switches

Crossings
A crossing or a frog is a device which provides two flangeways
through which the wheels of the flanges may move, when two
rails intersect each other at an angle.

Acute Angle Crossing

Diamond Crossing

Square Crossing

Track Junctions
 Turnouts
 Symmetrical split
 Three throw switch
 Double turnout or Tandem
 Diamond crossing
 Cross overs
 Single slip and double slip
 Gauntlet track and ladder tracks
 Temporary diversion
 Triangle
 Double junctions

Symmetrical split

https://www.youtube.com/watch?v=L_wOPY5Pu-A
How Railway Track Changes

Signalling
It consists of the systems,devices and means by
which trains are operated efficiently and tracks
are used to maximum extent,maintaining the
safety of the passengers,the staff and the rolling
stock.

On the basis of Operating
Characteristics:
 Detonating Signals (Fog or audible signals)
 Hand signals (Visual Indication signals)
 Fixed signals (Visual Indication signals)

Detonating Signal

Hand Signals

Fixed Signals

 Stop or Semaphore type Signals
 Warner Signals
 Shunting Signals (Disc or Ground Signals)
 Coloured-light Signals
On the basis of Functional
Characteristics:

Semaphore type signals

Warner Signals

Shunting Signals

Coloured-light Signals

 Reception Signals
◦ Outer signals
◦ Home signals
 Departure Signals
◦ Starter
◦ Advance Starter
On the basis of Locational
Characteristics:

Departure Signals

 Repeater or Co-acting signals
 Routing Signals
 Calling on signals
 Point indicator
 Modified lower quadrant semaphore
signal
 Miscellaneous signals
On the basis of Special
Characteristics:

High Speed Bullet Train
https://www.youtube.com/watch?v=2-_yS60NhyM

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Railway engineering By T.Ravi Prakash/Kongu Engineering College

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