Air brake system in indian railways

It is intersecting topic in a mechanical engineering flied which will full fill the things relative to the air brake system and also doubt regarding the brake system in railways .
As we seen the brake system in rails in your day to day life.

1. By N.Ram kumar AIR BRAKE SYSTEM

2. History This fail-safe air brake system is based upon the a patented by George Westinghouse in 1872. An air brake is a conveyance braking system causes by compressed air. After 1872 by using air braking system baker’s used to brake the wheel.

3. Introduction A brake is a device by means of which artificial resistance is applied to a moving body, in order to slow or stop the motion of the body. Brakes applied with the help of air pressure are called air brakes and the system causes is called as Air brake system.

4. Working principle In the air brake's simplest form in which compressed air pushes on a piston in a cylinder . The piston is connected through mechanical linkage to brake shoes that can rub on the train wheels, using the resulting friction to slow the train. The mechanical linkage can become quite elaborate, as it evenly distributes force from one pressurized air cylinder to 8 or 12 wheels.

5. Types of air brake systems T he air brake system is mainly classified into three types on the base of method and design development. 1.Straight air brake system 2.Westinghouse air brake system 3.Modern systems

6. Straight air brake Compressed air pushes on a piston in a cylinder. The piston is connected through mechanical linkage to brake shoes that can rub on the train wheels, using the resulting friction to slow the train . The mechanical linkage can become quite elaborate, as it evenly distributes force from one pressurized air cylinder. The pressurized air comes from an air compressor in the locomotive.

7. Westinghouse air brake Westinghouse invented a system wherein each piece of railroad rolling stock was equipped with an air reservoir and a triple valve, also known as a control valve. Unlike the straight air system, the Westinghouse system uses a reduction in air pressure in the train line to apply the brakes.

8. Triple valve The triple valve is described as being so named as it performs three functions: 1.Charging air into an air tank ready to be used. 2.Applying the brakes 3.Releasing them . In so doing, it supports certain other actions

9. Modern systems Modern air brake systems serve two functions : The service brake system The emergency brake system The service brake system, which applies and releases the brakes during normal operations . The emergency brake system, which applies the brakes rapidly in the event of a brake pipe failure or an emergency application by the engine operator .

10. The principal parts of the air brake system

11. The air is drawn into a compressor and stored in a main reservoir at 7-10 bar. Compressed air from the main reservoir is distributed along the train through the main reservoir pipe. On each vehicle, the pipe is connected through a triple valve to an auxiliary reservoir. The flow of air between the auxiliary reservoir and the brake cylinders is controlled through the triple valve or distributor. The control of the distributor is achieved by varying the pressure in a second pipe called the brake pipe, which is connected to a brake valve in the drivers cab. Increasing the pressure in the brake pipe causes the brakes to release, while decreasing the pressure causes the brakes to apply.

12. Brake in Release position

13. Brake in Application

14. TWO PIPES AIR BRAKE SYSTEM

15. The second pipe of the two-pipe system is the main reservoir pipe. This is simply a supply pipe running the length of the train which is fed from the compressor and main reservoir. It performs no control function but it is used to overcome the problem of critical loss of pressure in the auxiliary reservoirs on each car. A connecting pipe, with a one-way valve, is provided between the main reservoir pipe and the auxiliary reservoir. The one-way valve allows air from the main reservoir pipe to top up the auxiliary reservoir. The one-way feature of the valve prevents a loss of auxiliary reservoir air if the main reservoir pressure is lost.

16. Functions of components Compressor The pump which draws air from atmosphere and compresses it on the train. Main reservoir Storage tank for compressed air for braking and other pneumatic system. Feed pipe and Breaking pipe To ensure that the brake pipe pleasure remains at the required level.

17. Auxiliary Reservoir It is continuously charged through feed pipe. This ensures full break force during emergency in case of leakage in break cylinder. Distributor A distributor is simply a sophisticated triple valve. It is connected to Brake Pipe,Auxiliary Reservoir and Brake Cylinder . Triple valve The orientation of the brake on each vehicle is controlled by tripled valve.

18. Advantages The supply of air is unlimited, so the brake system can never run out of its operating fluid, as hydraulic brakes can . Air line couplings are easier to attach and detach than hydraulic lines. Air brakes are effective even with considerable leakage

19. Disadvantages Whole braking system fails due to leakage of fluid from brake linings. Additional cost is required to install this arrangement in the vehicle. Complex construction.