Air Brake System Of Indian Railways

Definition

The most vital factor in the running and control of any vehicle whether it is a cycle, scooter, car, bus, or train is the breaking system. In order slow down the moving vehicle in a shorter possible time, the energy of motion possessed by vehicle must be converted in to other forms. During break application in any vehicle the energy of motion is converted in to heat. This u might have noticed at the rim when you apply brakes repeatedly at short intervals.

Brake: brake is an arrangement provided in the vehicle for slowing down or bringing to rest a moving vehicle in the shortest possible distance.

Factor affecting the brake: The various factor that governs braking action in any vehicle are :-
1. pressure
2. surface area in contact
3. kind of material
4. heat generation.

Basic Requirements of brake:-

Keeping in the view the safety of human life and physical resources the basic requirements of brake are:

1. brake must be strong enough to stop the vehicle during an emergency with in a shorter possible distance.

2. there should be no skidding during brake application &driver must have proper control over the vehicle during the emergency.

3. effectivness of brakes should remain constant even on prolonged application or during descending on a down gradient.

4. brake must keep the vehicle in a stationary position even when the driver is not present

VACUUM BRAKE-

Brake application takes place when vacuum is destroyed by allowing air to enter to the system. During brake application piston is pushed inward.

LIMITATIONS OF VACCUM BRAKE SYSTEM:-

# Brake cylinder piston takes longer time to release after each application of brakes because single train pipe.

# successive brake application on gradients are not effective as piston takes longer time for release.

# vacuum brakes are not suitable for high speed trains the maximum pressure available for brake application is only atmospheric. Thebrake power is inadequate for higher loads and speed.

# brake power destroyed over the period of time as train run over long period.

AIR BRAKE

1. Brake application is takes place when pressure is dropped in brake pipe

2. during brake application the piston is pushed outward.

GRADUATED RELEASE AIR BRAKE SYSTEM

Graduated release air brake system is most suitable for Indian railways. Operation of graduated release air brake system consists of following stages:

*Charging
*Graduated Application and Emergency application
*Graduated Release
*For application of brakes pressure in brake pipe is dropped .
* Magnitude of braking force is proportional to reduction in brake pipe pressure.

Various stages of brake application are

- Minimum application 
- Service application
- Full service application
- Emergency application

* As compared to single pipe graduated release air brake system twin pipe graduated release air brake system is more suitable for passenger coaches.