Gauges of a railway track is defined as the clear distance between inner faces of two track. The distance between the inner faces of a pair of wheels is called the “wheel gauge”.

Different gauges in India and Abroad

• In 18th century, the British railways were using flanges on the outside of rails and the gauge was defined as the distance between the outer faces of the rails. The gauge then was 1.524 m. Subsequently, the adoption of flanges inside the wheel on rails, changed the definition of gauge.
• In India, the East India Company adopted 1.676 m i.e. broad gauge or standard gauge.
• In 1871, in order to build cheap railways for the development of the country (India), the govt. adopted a metre gauge i.e. 1 m.
• In hilly areas or poor areas, generally narrow gauge and feeder gauge is adopted.

Gauges in India

Gauges in different Countries

Selection of Gauge

How the choice of gauges is done, depends upon the following factors –

1. Cost of Construction – there is little increase in initial cost if we select B.G. This is due to the increase in land acquisition, wider construction of tunnel, bridges, cabins, level crossings etc. Cost of earthwork, ballast, sleepers, rails etc. increases also.
2. Volume and nature of traffic – For heavier loads and high speed, the wider gauges are required because subsequently the operating cost per ton-km is less for higher carrying capacity.
3. Development of the areas – Narrow gauges can be used to develop the thinly populated areas by joining the under developed areas with the developed areas.
4. Physical features of the country – In hilly areas, poor areas, light traffic areas use of N.G. is right choice.
5. Speed of movement – Speed of train is proportional to the gauge. Speed is the function of wheel diameter. The wheel diameter is generally 0.75 times that of gauge. So for maintenance of high speeds, the B.G. is preferred.

We can also have multiple gauges on a single rail track. Let us see an example of Dual gauge on a rail track –

Uniformity of Gauge

Gauge used in particular country should be uniform as far as possible. Because it will avoid many difficulties. The uniformity of gauges results in the following advantages –

1. The delay, cost and hardships in transshipping passengers / goods due to uniformity, thus avoided.
2. As the transshipping is not required; there is no breakage of goods.
3. Difficulties of loading and unloading will not be there.
4. Possibilities of theft and misplacement also will not be there.
5. Elimination of large sheds to store goods.
6. Labour strike etc. will not affect the service and operation of trains.
7. Due to uniformity, locomotives can be effectively used.
8. During military movements, there is no time waste in changing personnel and equipments.
9. It is quite expensive to convert one gauge to another on later stage.
10. The porter charges are increased; when passengers have to change compartment due to a different gauge. Thus avoided if gauge is uniform.