Disc Brake vs Drum Brakes, Which is the Best Braking System?
In recent years, brake technology has advanced significantly. What began as a genuine endeavour around the middle of the 20th century to provide appropriate braking for fast cars has evolved into a sector where brakes range from highly reasonable to exceptional. Components like carbon fibre, pressed metal, ultra-light steel, and the use of ABS have all resulted in shorter stopping distances and overall safe and secure automobiles.
In the early 1970s, manufacturers shifted from drum to disc brakes on a large scale, which was one of the first moves to improve braking. Because the front wheels carry most of a vehicle's halting force, only the front brakes were updated to disc and drum brakes for the back of the automobile to save money on manufacturing and purchase expenses.
How braking works
The pace at which a tire can be halted is determined by several elements such as vehicle weight, stopping force, and overall braking surface area. It also depends on how successfully a braking system transforms wheel motion into heat (by friction) and then releases that heat from the brake components fast. This is where the distinction between the drum and disc brakes becomes clear.
Drum brakes
Drum brakes got their name because the mechanisms were contained in a round drum that spun with the wheel. When the brake pedal was pressed, the shoes were forced against the drum, slowing the spin. The brake shoes were made of a heat-resistant friction substance, and fluid was used to translate the brake pedal's action into the brake shoes' motion. Under most circumstances, this fundamental concept worked well, but it had one big drawback. Drum brakes typically fade and lose efficacy in extreme braking situations, such as descending a steep hill with a large load or slowing down at high speeds. This fading was generally caused by the generation of heat within the drum. As a result, drum brakes can only operate for as long as the heat generated by a slowing vehicle can be absorbed. When the brake module becomes saturated with heat, they gradually lose its ability to stop an automobile, which can be alarming for the driver.
Disc Brakes
Disc brakes use the same fundamental concept as drum brakes to decelerate an automobile (friction and heat); its layout is significantly superior. Disc brakes employ a thin rotor and a small calliper to stop tire motion. When the brake pedal is applied, two brake pads on either side of the rotor clasp together within the calliper. Fluid is again utilised to control brake pad motion through the brake pedal. Unlike drum brakes, which permit heat to ramp up inside the drum during severe braking, disc brakes' rotor is wholly exposed to the outside air. This exposure keeps the rotor cool continuously, lowering the chances of it overheating or fading.
Drum vs Disc
Most new automobiles still use front-disc/rear-drum brake systems. Today's disc/drum brake systems are more than adequate for most new-age cars. This combination works well overall as Drum brakes are cheaper and help reduce the vehicle's overall price.
Drum brakes have some design problems. They overheat fast, take longer to dry, and are often heavier than disc brakes. At the same time, because disc brakes expand when hot and shrink when cold, they cannot be utilised as a parking brake. We'd have challenges.
It's only that the two brakes aren't the same. Disc brakes are the most effective and reliable option, but they are not without drawbacks. Drum brakes are inconvenient, but they are necessary for parking a car.
Pros – Drum Brakes
- Drum brakes are inexpensive to produce since the components are simple to fabricate. This also keeps the vehicle's final price low.
- Parking brakes can be housed in drum brakes without taking any additional space.
- Refurbishing a wheel cylinder is simpler than reconditioning disc brake callipers.
- Drum brakes require lesser force to apply brakes due to their design.
Cons- Disc Brakes
- Disc brakes are expensive to set up and manufacture, which raises the overall vehicle price.
- A small amount of air in the master cylinder might cause the disc brakes to malfunction altogether, resulting in significant accidents, which is why brake bleeding is recommended during vehicle maintenance.
- Brake fluid must be changed frequently to avoid becoming less dense.
- A disc brake without an anti-lock braking system (ABS) has a very high risk of slipping and locking the tires.
Pros – Disc Brakes
- Despite their compact design, Disc brakes have tremendous power and can halt high-speed cars better than drum brakes.
- The open design of the disc brakes allows for excellent heat absorption, guaranteeing that they never overheat.
- Since they are open, they do not accumulate any undesired particles and hence do not rust or deteriorate performance.
- Disc brakes with ABS do not lock up when used for high-speed braking. Previously, they had concerns with the vehicle locking up and losing control. Their biggest flaw has now become a strength, thanks to ABS.
Cons – Drum Brakes
- Drum brakes have poor heat dissipation, resulting in metal parts overheating and minor expansion.
- Since it is closed, it can gather undesired particles, causing problems like corrosion and lowering piston efficiency.
- They wear down quickly due to the quantity of heat they release. Most parts do not have a long life due to severe heat and significant friction.
- Since so many components are involved, the risk of failure is relatively significant.
Disc brakes are still the best choice, even though both are now employed in most cars, with disc brakes in the front and drum brakes in the rear. Drum brakes, on the other hand, cannot be ruled out. They can be an excellent long-term investment due to their low cost and ease of maintenance. As discussed earlier, in normal Indian conditions, a combination of disc-drum brakes works fine, though, for high speeds and ultimate braking performance, disc brakes serve the purpose better.