Advantages & Disadvantages of Hydraulic Brake System

Perhaps the most important component of an automobile is its braking system. There are different types of braking systems available in the market which are based on different mechanisms. Most braking systems use the friction between two surfaces to stop the motion of the vehicle.

The brake system which uses the pressure of a fluid to operate is called a Hydraulic Brake System. This system is being used in automobiles for a long time. This mechanism uses fluid to transmit force to the system.

In this article, we will cover the Principle, components, working, advantages, and disadvantages of Hydraulic braking Systems.

Principle

The Hydraulic Braking system works on the principle of Pascals Law, which states that the pressure change in any confined incompressible fluid is uniformly distributed at every other point in the container.

In other words, when pressure is applied to a liquid at a point, then it travels equally in all other directions. The hydraulic Braking system uses this principle to its advantage by uniformly distributing the pressure applied by the brake pedal to all the wheels, thus reducing the speed of the vehicle.

Components of Hydraulic Braking Systems

Following are some of the components of the Hydraulic Braking System

1. Master Cylinder:- The role of this cylinder is to convert the force applied by the driver to fluid pressure. This is the most important component in a Hydraulic braking System. This is the cylinder that holds the fluid and sends it through the brake lines to activate the braking mechanism.
2. Brake lines:- These are the lines that are responsible for carrying fluid between the components of the system. These are generally made up of steel.
3. Wheel Cylinders:- These are present in all wheels of the vehicles. These cylinders help in converting the hydraulic pressure to mechanical pressure in the wheels to create friction.
4. Brake Fluid:- The fluid which is to be chosen to be filled in the system must have good lubrication, low freezing, and high boiling points. Moreover, the liquid used in this system should not be considerably compressible. Some common fluids which are used in this system are DOT2, DOT3, DOT4, DOT5, and DOT5.1 ESP.
5. Brake pedal:- This is the component that you push in the car to activate the braking mechanism of the vehicle.

Working of Hydraulic Brake systems

The brake pedal is connected to the master cylinder, which helps in transferring pressure to all the wheels. When the brake pedal is pressed, the fluids in the master cylinder compress due to the increased pressure. This pressure is then transferred to all four wheels by the master cylinder. This pressure is then transferred to the pistons which are present in all four wheels, which eventually force the brake shoes to make contact with the brake drums, to stop the motion of the wheels.

A similar process is involved while releasing the brakes. When released, the cylinder regains its original position, thus reducing the fluid pressure in the system and the wheels. This causes the pistons in the wheels to come back to their original positions, which in turn relaxes the brake shoes to return to their original position.

Advantages of Hydraulic System

Pressure Uniformity

In a basic mechanical brake system, the pressure is not distributed uniformly. However, in the Hydraulic Brake system, the pressure is uniformly distributed over all wheels which ensures that the braking mechanism is smooth and reliable.

Less force required

A hydraulic brake system can generate more force in less effort when compared to the mechanical braking system because the force applied by the driver is multiplied several times when passed through the cylinder.

Reduce Frictional Losses

Since the Hydraulic Braking system uses fluids to function, these act as lubricants and avoid wear and tear. This results in the longevity of this braking system as compared to other braking systems.

Simple Construction

The construction of a Hydraulic braking system is not very complex. This also reduces the construction costs of this system.

Disadvantages of Hydraulic System:

1. Fluid Leakage

The biggest disadvantage of this system is its complete reliability on fluids. The whole mechanism is based on the fluid-filled in the brake linings. If the fluid starts to leak out from the linings, the whole braking system might fail.

Vulnerability to Air and Extreme Heat

Preventive measures have to be taken to avoid the entry of gas into the fluids. The presence of gas in the system does not allow the fluid to pass the pressure uniformly, hence disrupting the system. Heat leads to the formation of air bubbles in the fluids and makes them ineffective in transmitting pressure from one place to another.

High Maintenance costs

Although the construction costs of this braking system are low, the maintenance cost of this system is high. This is because the system has to be checked often to prevent fluid leakage and entry of gases Into the system.

I hope this helps you understand the advantages and disadvantages of a Hydraulic brake system.