One kilometre of Indian broad gauge main line holds up to 1,660 sleepers. With elastic fastenings, that means roughly 6,600 rail clips, 6,600 liners and 3,300 rail pads, all before you count fish plates, bolts and turnout fittings. A railway track is not two steel rails on stones. It is a system of thousands of parts sharing one load.
This guide explains each component of railway track: rails, sleepers, fastenings, ballast, formation and turnouts. We cover what each part does, the common types, and how they work together. It is written by a manufacturer of track fastenings, steel sleepers, turnouts and rolled sections.
What Is a Railway Track (Permanent Way)
Railway track is also called the permanent way. It is made of rails fixed to sleepers with fastenings, resting on a ballast bed laid over a prepared formation.
The track has three jobs:
- Guide the wheels along a fixed path
- Spread heavy wheel loads safely into the ground
- Hold gauge, line and level under repeated traffic
Track Gauge
Gauge is the clear distance between the inner faces of the two rail heads. India uses:
- Broad gauge: 1,676 mm, the main network standard
- Metre gauge: 1,000 mm
- Narrow gauge: 762 mm or 610 mm, mostly on hill and heritage lines
Main Component Parts of Railway Track
Every ballasted track is built from the same core parts:
- Rails
- Sleepers
- Fastenings and fittings
- Ballast
- Formation or sub-grade
- Turnouts and special components
Rails
Functions of Rails
Rails give wheels a hard, smooth running surface. They carry the vertical wheel load, resist lateral forces on curves, and pass the load down to the sleepers. On electrified and signalled routes, rails also carry return current and track circuit signals.
Types and Sections
Modern track uses flat-footed rails. Indian Railways main lines use 52 kg/m and 60 kg/m sections, with head-hardened rails on heavy haul and high-wear locations. Light rails serve industrial sidings, mines and crane tracks.
Rail Joints and Welding
Rails are joined either with fish plates and bolts or by welding. Long welded rails remove most joints, which cuts maintenance and gives a smoother ride. Insulated joints, often glued, separate track circuits for signalling.
Sleepers
Functions of Sleepers
Sleepers sit under the rails at right angles. They hold the gauge, spread the load into the ballast and keep the track in line and level.
Types of Sleepers
- Prestressed concrete (PSC): Standard for Indian main lines today
- Steel sleepers: Light, durable and easy to handle, used on bridges, sidings and industrial track
- H-beam steel sleepers: Used on bridges and special locations
- Wooden sleepers: Now limited to special uses
- Cast iron sleepers: Largely phased out
Sleeper Density
Sleeper density is the number of sleepers per kilometre. Indian broad gauge main lines typically use 1,540 to 1,660 sleepers per km. Higher density spreads the load over more ballast and suits heavier, faster traffic.
Fastenings and Fittings
Fastenings lock the rail to the sleeper. They look small, but they control gauge, absorb vibration and stop rails from creeping.
Fish Plates and Bolts
Fish plates are a pair of steel bars bolted to the rail web at a joint. They keep rail ends aligned and transfer load across the gap.
Base Plates
Base plates sit between the rail and the sleeper, especially on steel and wooden sleepers and in turnouts. Cast base plates are used heavily in turnout areas.
Elastic Rail Clips, Liners and Rail Pads
Elastic rail clips press down on the rail foot with a constant spring force. Metal or nylon liners position the rail and insulate it. Rubber rail pads under the rail foot absorb impact and protect the sleeper.
Here is the part most project teams underestimate. The total value of clips, liners and pads on a kilometre of track is small next to rails and sleepers. Yet loose or worn fastenings are one of the most common sources of gauge and alignment defects.
Anchors and Screws
Rail anchors resist creep, the slow lengthwise movement of rails under braking and temperature change. Rail screws fix rails or base plates on certain sleeper types.
Ballast
Functions of Ballast
Ballast is the bed of crushed, angular stone under and around the sleepers. It:
- Spreads load from sleepers to the formation
- Holds sleepers in place against lateral and longitudinal forces
- Drains rainwater away quickly
- Allows the track to be lifted and levelled by tamping
Ballast Depth and Quality
Indian broad gauge track typically has 250 to 300 mm of ballast below the sleeper, with a clean cushion of about 300 mm on heavy haul routes. Hard, angular stone is used so the pieces lock together. Rounded stone rolls and lets the track drift.
Formation and Sub-Grade
The formation is the prepared ground that carries the ballast. A blanket layer of coarse soil is often laid on top to stop water rising into the ballast. A weak formation causes recurring track settlement, no matter how good the components above it are.
Turnouts and Special Track Components
Turnouts let trains move between tracks. Their main parts include:
- Stock rails and tongue rails
- Lead rails and check rails
- Crossings, often cast manganese steel
- Slide chairs, stretcher bars and spring setting devices
Other special components include expansion joints at the ends of long welded rails and on bridges, and glued insulated rail joints for signalling.
Ballasted vs Ballastless Track
Most Indian track is ballasted, but ballastless track is growing on metros, tunnels, bridges and some high-speed corridors. India laid its first 1 km trial of ballastless track on a main line near Delhi in 2006.
| Point | Ballasted Track | Ballastless Track |
| Base | Crushed stone bed | Concrete slab |
| First cost | Lower | Higher |
| Maintenance | Regular tamping and cleaning | Very low |
| Adjustment | Easy to lift and realign | Limited, done through fastenings |
| Typical use | Main lines, sidings, yards | Metros, tunnels, bridges |
On ballastless track, the fastening system does even more work. With no ballast to absorb shocks, rail pads and base plates carry the job of elasticity.
How the Track Carries a Train’s Load
- The wheel presses on the rail head over a tiny contact patch
- The rail spreads that load over several sleepers
- Rail pads cushion the impact at each rail seat
- The sleeper spreads the load into the ballast
- The ballast spreads it further into the formation
At each step, pressure drops. By the time it reaches the ground, a very high contact stress at the wheel has been reduced to a level the soil can carry.
How to Source Track Components
When buying track materials, check:
- Specification and approval match for each item
- In-house manufacturing of fish plates, base plates, sleepers and turnouts
- Material traceability through heat numbers and test certificates
- Testing labs for chemical, mechanical and metallurgical checks
- Single-source supply to reduce coordination across vendors
- Export experience for overseas projects
Frequently Asked Questions
What are the five main parts of railway track?
Rails, sleepers, fastenings, ballast and formation. Turnouts are added wherever trains need to change tracks.
Why are steel sleepers still used when concrete is the main-line standard?
Steel sleepers are light, quick to lay and need less ballast depth. They suit bridges, sidings, industrial yards, mines and locations where handling heavy concrete sleepers is difficult.
What is the purpose of a rail pad?
A rail pad sits between the rail and sleeper to absorb vibration and impact. It protects the sleeper and reduces noise and wear on fastenings.
What is rail creep?
Creep is the gradual lengthwise movement of rails caused by braking, acceleration and temperature changes. Anchors and elastic fastenings resist it.
Conclusion
Railway track works as one system. Rails carry the wheels, sleepers hold the gauge, fastenings lock everything together, ballast spreads the load and drains water, and the formation carries it all. Turnouts and special components handle the points where the track changes direction or expands. Weakness in any one part shows up as defects in the others.
If you are planning a new line, siding or track renewal, send us your bill of materials for a single-source quotation.
Complete Track Solutions from Jekay International
Jekay International Track Pvt. Ltd. has supplied railway developers, governments and private operators in India and 27 countries since 1980. We manufacture fish plates, base plates, elastic fastenings, liners, rail pads, anchors, steel and H-beam sleepers, glued insulated rail joints, expansion joints and complete turnouts. Our 1,00,000 MT rolling mill rolls the fish plate, liner and sleeper sections behind these products.
We promise a single, accountable source for your track components, from rolled section to finished fitting.