Air Brake System: Diagram, Parts, Function, and Application [PDF] (2023)

In this article you will find outWhat is the air brake system?They areparts diagram,job benefits,jto shapeeverything is explained with pictures.

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What is the air brake system?

Drivers rely heavily on their brakes when hauling thousands of pounds in trucks. Himbreaking systemOn large trucks, buses and tractor units, it consists of air brakes. Air brakes are the safest option for large vehicles.hydraulic fluidscan leak and cause accidents.

Like a friction brake, an air brake uses compressed air to put pressure on youPistonsto apply the necessary pressure to the brake pad or shoe to stop the vehicle. Air brakes are used on large and heavy vehicles, especially those with multiple trailers that need to be connected to the braking system.

Em 1872,George Westinghousedeveloped a safe compressed air brake for use in rail traffic for the first time. He made several changes to improve his invention of an air brake, resulting in several automatic brakes.

Being a major part of diesel vehicles, you need to know how air brakes work and what parts they are in order to service an air brake system. So let's start.

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parts of the air brake system

The following are the important parts of the air brake system:

1. Air compressor
2. storage tank
3. brake pedal
4. brake drum
5. safety valve
6. break the lining
7. mud flaps
8. brake actuator
9. triple valve
10. air filter or dryer

See Also

Air Brake System - Parts, How It Works, Diagram, Principle, Benefits | learn mechanical engineering

Air compressor No. 1

HimAir compressorhelps draw atmospheric air into the storage tank or holding tank. It compresses air to the desired pressure and sends it to the storage tank. An air compressor is driven by the engine via aTrain belts. A compressor can be air-cooled or air-cooled.engine cooling system.

Storage Tank #2

The purpose of a storage tank is to safely store the compressed air supplied by the compressor. It is an essential part of the air brake system, since compressed air is responsible for its correct operation.

It stores enough air and allows multiple stops if the engine stalls or the compressor fails. On a vehicle, the size and quantity of the reservoir depends on how many brake cylinders there are, their size, and how the parking brake is configured.

#3 Brake Pedal

An air braking system is operated by driver input. The brake pedal is the main part that activates the brakes to stop or slow the vehicle. It is a type of mechanical linkage that transmits input motion to the feed mechanism. When the brakes are applied, compressed air is sucked into the tires, which in turn brings the vehicle to a standstill.

#4 Brake drum

The brake drum is the only part of the system that performs the braking process. When the vehicle stops or brakes, the brake drum transmits the braking force to the wheel in the form of friction between the brake pads and the drum lining.

The outer part of the brake drum has a drum lining that rotates with the wheel, and the inner part, which contains the brake shoes, stays still when the brake pedal is not depressed. A brake drum is generally used in air brake systems, but with the correct arrangement.

#5 safety valve

A safety valve is usually installed in the accumulator near the compressor. A safety valve prevents the accumulator from being over pressurized as the compressor works continuously to supply air.

It consists of a spring-loaded ball that allows air to escape from the reservoir to atmosphere. When the air pressure reaches certain values, the safety valves release the air.

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Foot valve No. 6

The function of the foot valve is to draw compressed air from the reservoir when braking. Depending on the pedal travel or the brake pedal, the driver regulates the amount of air supplied to the brakes.

By moving the foot valve pedal, the rider controls the amount of air pressure applied, but the maximum pressure must not exceed that of the reservoir. Releasing the foot valve pedal releases the brakes.

#7 brake pad

These are called umbilicals. The transfer of compressed air from the reservoir to the brake drum is accomplished simply by interrupting the brake lines connecting the reservoir to the brake drum.

#8 Mud Flaps

Typically, a mud flap is placed in the brake line and branch pipe. Collects dirt particles that are separated by theair filter. This helps separate dust from the compressed air flowing through the brake line, allowing only clean air to enter the valve and reservoir.

Brake actuator #9

A brake actuator is a device consisting of a piston and cylinder assembly that is directly connected to the brake pedal. When the rider presses the pedal, pressure builds up across the entire assembly.

#10 triple valve

A triple valve is also an important part of the air brake system. It is used to apply and release the brakes, which requires a continuous apply and release mechanism. It applies pressure as soon as the pedal is pressed and releases pressure immediately when the pedal is released.

No. 11 air filter and dryer

As the name suggests, air filters remove dust particles from the atmospheric air while the dryer inlet removes moisture. If the compressed air brake system does not have a dryer, condensation will form in the lines and air reservoirs, which will lead to brake failure in winter due to condensation icing.

Also read:Drum Brakes vs. Disc Brakes: Which Brake is Better?

Structure of the compressed air brake system

An air braking system consists of a two-stage air compressor driven by thecrankshaftÖtransmissionAxis. In this braking system, air is taken from the atmosphere, compressed and fed through an exhaust valve into the reservoir.

When the tank pressure reaches the maximum level, the exhaust valve opens to atmosphere. The compressed air is then released directly into the atmosphere.

Every vehicle wheel equipped with brake chambers has a diaphragm to which air pressure is applied and pressed. This action creates a force that actuates thehe takessteering lever and operates the brake. There is an air filter between the brake valve and the reservoir of each brake chamber, and the chambers are connected to the brake pedal.

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Operation of the air brake system

The figure above shows the layout diagram of the air brake system. These brakes typically consist of an air filter, wastegate, air compressor, air reservoir, brake valve and brake cylinder.

First, the compressor draws in air from the atmosphere through an air filter. The air filter filters the air and sends it to the compressor, where it is compressed. This pressurized air is then routed to the tank through a relief valve, which opens at a predetermined tank pressure and is connected to a brake valve.

From the brake valve, the pipe leads to the front and rear brake cylinders. Air is supplied to the brake chambers of each wheel through brake valves. It is controlled by the driver, who can determine how hard to brake.

applied brake

In the diagram above, full system pressure air is routed through the dark (red) shading into the brake line connecting the reservoir to the foot valve. The driver takes over the braking work. This can be seen in the lightly shaded (pink) connection lines between the foot valves and the air chambers.

When the pedal is depressed, air from the reservoir is compressed and directed through the brake valves evenly in all directions to further apply the brakes.

brake released

In the image above, the driver's foot is off the brake pedal and releasing the brake. This opened the exhaust port at the bottom of the foot valve, allowing air to escape from the brake cylinders.

As soon as the brake pedal is released, the return spring does itmaster cylinderThe piston returns to its original position and reduces the pressure. Now the brake shoe return spring has pushed the brake pad away from the brake drum.

Also read:10 Common Brake Problems Every Driver Should Know

Advantages of the air brake system

1. These brakes contain an air tank that stores enough energy to stop the vehicle if the compressor dies.
2. Air brakes are more effective than other brakes.
3. They are also effective in the event of a leak, so an air braking system can be designed with sufficient capacity to safely stop the vehicle even in the event of a leak.
4. All that is needed to actuate the brake is air, which is readily available.
5. Compressed air can be used for ancillary applications that are not suitable for hydraulic systems, such as B. Air horns and seat adjusters.
6. Air line couplings are less expensive to connect and disconnect than hydraulic lines.
7. Offers greater braking power and better control over the system.
8. With this system, the wear of its parts is less.

Disadvantages of the air brake system

1. Air brakes are generally more expensive thanhydraulic brakes.
2. This compresses the air, creating moisture that must be removed with an air dryer, making the system more expensive and potentially leading to high maintenance and repair costs.
3. A defective tumble dryer leads to ice formation on the pneumatic brake system in winter.
4. Air brakes produce noise in the 95 to 115 dB (decibels) range, with levels approaching 115 to 120 dB for a typical noise level range that can cause immediate hearing damage.
5. If a leak is found en route, the entire system will fail, making it very difficult to seal the air.
6. Air brakes will not work underwater or in extreme temperatures.

Application of the air brake system

1. The use of air brakes is becoming necessary for many trailers, high-speed long-distance buses, military vehicles and tractor-trailers.
2. George Westinghouse invented air brakes for trains.
3. After proving their effectiveness on trains, air brakes were later adapted for heavy vehicles.
4. They are also used on small vehicles, but there is less room to operate the air brakes.
5. There are also air brakes used on buses for braking.

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