Brake is a mechanical device which is used to absorb the energy from a moving system by means of friction. The main purpose of the brake is to slow down or completely stop the motion of the moving system like wheels of automobiles, rotating the drum and any kind of machinery. We can say that brakes are an important part of any moving system and work as a safety device also.

Braking is done due to the friction between two surfaces. Brakes can also be used to hold the objects in the rest position. Brake absorbers energy in two forms i.e. kinetic and potential energy. In case of running automobile brake absorb the kinetic energy of moving vehicles. In elevators and hoists brake absorbers the potential energy released during the braking.

The brakes are applied by means of friction so the energy absorbed by the brakes is converted into heat energy which is dissipating to the surrounding. The heat generated during the braking is a major problem in brake applications. Now a day’s different types of brake are used where this heating problem is resolved up to some extent. Generally, brakes are classified in three main categories these are a mechanical brake, hydraulic and pneumatic brakes and electric brakes.

Here we will study about the main differences between the drum bake and disc brakes. Both the brakes come under the category of mechanical brakes. The braking capacity of different types of brakes is depended upon the various factors like pressure between the braking surfaces, area of contact between braking surfaces, diameter/radius of the brake drum, coefficient of friction between contact surfaces and the rate of heat dissipation.

Difference between disc brake and drum brake

   DRUM BRAKE                          DISC BRAKE
The drum brake is a small drum which rotates with the wheel in case of automobile and has a pair of shoes known as brake shoes inside it. When the brake paddle is pressed then the brake shoes are forced against the side of the walls of the drum and apply brake by means of friction.

The disc brake has a disc-shaped metal plate and a calliper which is attached to the wheel and disc is rotates with the wheel of an automobile. The calliper is used to exert force on the pads.  The friction lining of the calliper comes in contact with a small portion of the disc. The reaming portion of disc helps in dissipation of the heat to the surrounding. Two pads on either side of the disc are used and the friction lining is attached to both pad. Calliper is attached to the non-rotating member and exerts force on both the pads. When brake paddle is pressed then pads are also pressed against the rotating disc then the friction between the disc and pads retards the speed and stop the disc.
Drum brakes are pure mechanically operated.Disc brakes are mechanically operated but they can also be linked with ABS system and some other advanced technologies.
In the drum, brake water is collected inside the drum when the vehicle runs in water or at washing time. This water accumulating affects the efficiency of braking.They work efficiently in adverse conditions like in heavy rains and there is no such effect of water in case of disc brakes.
Drum brakes are not effective at high speed because at high speed when the brake is applied then due to friction lager amount of heat generates due to this overheating occurs. As temperature increases the coefficient of friction decreases due to this friction lining fade away and loss of torque transmitting capacity of friction lining at a higher temperature.In case of disc brakes, no overheating occurs because only a small portion of the disc comes in contact with the friction pads and rest area of disc helps in better dissipation of heat. So they can be used in high-speed applications. The coefficient of friction is not changed very easily and the friction lining does not fade away easily.
Drum brakes have less torque transmitting capacity.Disc brakes have high torque transmitting capacity in a small volume.
Its response time is high as compared to disc brakesDisc brakes are as easy to control and have fast response time as compared to drum brake.
This may be self-lockingDisc brakes never be self-locking
Drum brakes are used in heavy vehicles due to the self-actuating properties i.e. when the corner edges of the brake pad come in contact with outer cover then the rest of brake pad comes in contact itself so less effect is required by the driver.Disc brakes generally used in medium and low vehicles because there is no self-actuating property.
Less effective in different applications and heavy in weight as compared to disc brakesMore effective in different applications and light in weight.
Here is no fluid is used so it does not require any kind of maintenance when the vehicle is used after a long time.When a vehicle is not in use for a long time then the chances of damage of brake fluid pipe increases which causes failure in braking and require maintenance and braking fluid may lose its viscosity which should be replaced.
In case of drum brakes for inspections and service of the brake; wheel and drum are dissembled first because brake parts like pad brake shoes etc are attached inside the drum.Disc brakes are easily inspected without removal of the wheel because it is mounted with the wheel so the defaults in the brake visually inspected very easily.
Drum brakes are not completely self-adjusting and less efficient than disc brakes.Disc brakes are better stopping power than drum brake and completely self-adjusting, so overall performance of the disc brake is better than the drum brake.
The maintenance of drum brake is cheaper than disc brakeMaintenance cost is high if we used disc brakes.


This is all about the main difference between disc brake and drum brake. If you have any query regarding this article, ask by commenting. If you like this article, don’t forget to share it on social networks. Subscribe our website for more informative articles. Thanks for reading it.

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