Lecture 12 Final

CE-363

Lecture 12: Rail Fastenings

Dr. Ankit Gupta, Assistant Professor

Department of Civil Engineering

National Institute of Technology Hamirpur

Lecture Outline

Track Fittings

Rail to Rail Fittings

Rail to Sleeper Fittings

Fastenings - Types

Rail to rail joining

Rail to wooden sleeper fitting

Rail to steel trough sleeper

Rail to CI sleeper

Elastic fastenings

Fish plates, bolts, nuts

Dog spike, Fang bolts,

screw spikes, bearing

plates

Loose jaws, keys and

liners

Tie bars, cotters

Elastic or Pandrol clip,

IRN 202 clip, rubber pads,

HM fastening, MCI insert,

nylon liners

Fastenings Rail to Rail

Fish Plates

IRS T-1/57

UTS Min 58 67 kg / mm2

Min elongation 20%

Sectional area = rail

section

Strength = 55% of

rail section


Fish Plates


Combination Fish Plates

Join two different rail sections

Additional thickening of joint

Elimination of expansion gap

Fish plates marked as right in / out, left in /

out depending upon direction from lighter

rail to heavier rail

Fastenings Rail to Wooden Sleeper

Spikes

Dog spikes


Spikes

Round spikes (with anti-creep bearing plates; chairs of BH rails)


Spikes

Screw spikes (for high speed trunk routes, Plate screw, Rail screw)


Bolts

Fang bolts (for slide chairs / sleepers, under switches)


Bearing Plates

MS canted BP (for joints and curves, 1 in

20)

Flat MS BP (for points and crossings, with

dog spike)

CI anti-creep BP (ACB plate) (for creep

affected locations, 1 in 20, round spikes)

Special CI BP for BH rail (with spring key)


Bearing Plates MS canted BP


CI Bearing Plate for BH rail


Chair and Slide Chair

Fastenings Rail /Steel Sleepers

Loose jaws

Spring steel loose

jaws with keys, No

problem of

damaging,

cracking or

deforming, easily

replaceable.


Two way keys

Taper 1 in 32, for trough sleepers, pot

sleepers, CST-9 sleeper.

190mm long, 1 in 32 taper


Rubber coated / Epoxy coated fish plates

Rubber coated used on insulated joint,

damages early.

Now epoxy coated fish plates are used


Mota Singh Liner

For loose jaws to overcome the problem of

elongated holes.

Fastenings Rail with CI sleeper

Cotters

Fixing tie bars with CI sleepers

Central split cotter

Side split cotter

Solid end split cotter

Bent plate cotter

Fastenings Rail with CI sleeper

MS Tie Bars

Hold two plates of CST-9 sleeper together

Length 2720 mm, section 50 mm x 13 mm

for BG

Fastenings Elastic: Requirements

Adequate toe load

Sufficient elasticity to absorb shocks and

vibrations

Should hold gauge and maintain track

Resist lateral forces

Fit and Forget type, least maintenance

Reusable, cheap and long life

Universal type, sabotage free

Fastenings Elastic: Types

Pandrol / Elastic clip (PR 401 clip)

Fit and forget type

Toe load 710 kg for nominal deflection of 11.4 mm

Universal

Use base plate and CI inserts

Gauge adjustment difficult

Point contact causes indentation on rail foot

Theft prone


IRN 202 clip

For two block RCC sleeper

Toe load 1000 kg for deflection of 18.5 mm,

Creep resistance ~ 50% of toe load

Bolts and clamps required

Removal of rail easy

But not fit and forget type

Costlier

Heavier and problem of corrosion


Elastic Rail clip (MK III)

Used with rubber pads, 2 liners of 6mm with

60 kg rail and 1 liner each of 16 mm on non-

gauge side and 10 mm on gauge side with 52

kg rail.

Toe load 900 1100 kg with deflection 15.5 mm.

But not interchangeable

Theft prone

Loosening of toe load, jamming / rusting.


Interchangeable Fastening H.M. Fastening

Clip wt. 510 gm

Toe load 1t

Provide dampening effect and resistance to

lateral movement

Used with grooved rubber pads, insulator,

plastic dowel and angled guide plate.

Maintains gauge.


FASTCLIP FD

This is a simplified system for railways

operating low or medium density

operations, on rail sections of 50kg or

below and at speeds generally less than

120km/hr.


Malleable CI Inserts

Fixed directly into the concrete sleeper during manufacturing.

Stem type for normal pre-tension concrete sleepers, wt. 1.6 kg per piece.

Gate type for post-tension concrete sleepers, wt 1.7 kg per piece.


Rubber Pads

Absorb shocks

Damp and absorb vibrations

Resist lateral movement of rails

Prevent abrasion of bottom surface of rail

Provide electrical insulation.


Composite Liners

With malleable CI and nylon components

or with MS and nylon components.

Glass Filled Nylon Liners

Used for track circuiting areas, sections

subjected to severe corrosion, superior,

single piece, long life, corrosion free.


GFC 66 Liner

Rust free surface of rail with 1 in 6 slope of

rail flange, 6mm thick, used with ERC clip,

may damage due to rusting, uneven

seating or in yards

Material Requirement on Track

Computed as per km

Rails (in Nos. and weight)

Sleepers (Nos., based on sleeper density)

Fish Plates (@ 2 per rail)

Fish Bolts / Holes (@ 4 per rail)

Bearing Plates (@ 2 per sleepers)

Spikes Dog spike (@ 4-6 per sleeper on straight track; 6-8 per sleeper on curved

track)

Documents

Lecture 12 Final