Why don't train wheels slip on rails, whether metal or metal drives metal? This is probably the most frequently asked question about rail functionality.

Remember the law of friction.

Friction is the force that resists the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.

wheel set

Put one of your palms on the other. Now start kneading. It may slide easily. Now apply pressure with both hands and start rubbing. This time it wasn't easy.

What was the difference the second time? The pressure applied by the hand increases friction. And this friction is the opposite of sliding.

In the field of railway practice.

Come to the railway. The heavy weight of the carriage can be seen as a great force. This force creates friction between the wheel and the rail. Therefore, when pulled by a locomotive, the wheels do not slip on the rails.

How does friction actually act on the wheels and tracks to make the train run on the truck?

According to Ammonton's first law of friction, "the force of friction is proportional to the applied load". The force applied here refers to the weight of the wagon, passenger car or locomotive itself.

This load (force) passes through the wheel and eventually reaches the track. This gravitational force of a carriage, carriage, or locomotive creates an imaginary force.

The weight of the wagon is transferred to the railroad tracks via ball bearings mounted on the axles. Two frictional forces are created here.

 One is in the ball bearing and the other is between the wheel and the track. In ball bearings, the friction is the lubricating friction.

The friction between the wheel and the track is dry friction. Usually dry friction is greater than lubricated friction.

When the locomotive starts to pull, the train starts to travel through the rolling motion of the wheels because the friction of the ball bearing is less than the friction between the wheels and the track.

But in practice, wheel slip occurs in various situations.

Yes, wheel slip happens on rails too. The locomotive driver has to control wheel slip through some technical application as well as his own experience.

 We locomotive drivers use three activities to reduce wheel spin during the rainy season.

1. We used to blast the rails with two sandboxes mounted on either side of the front wheels.

These sandboxes must be filled with sand, and it is the responsibility of the Loco driver to check that the sandbox is full of sand and that the sanding system is in working order before taking charge of the Loco.

Locomotive drivers can sandblast the track with a paddle switch in the locomotive cab. Sandblasting is very useful to create more friction between the track and the wheels, reducing wheel slip.

2. We reduce the current in the traction motor through the main controller.

The Loco driver presses a special pushbutton switch mounted in the cab to reduce the current differential between all traction motors by connecting a temporary resistor to each traction motor.

It reduces the current differential between the traction motors, thereby reducing wheel slip.

3. It is practical experience. When wheel slip begins, we use local braking to effectively reduce wheel slip.

If after all these techniques the wheel slip does not stop, the locomotive driver must stop his train. After a while, when things return to normal, he should start his train.

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