Shock Absorbers

Shock Absorbers

For the smooth running of your car, a lot of action goes on underneath. Taking center stage in your car’s hydraulic system is what we call dampers or in other words shock absorbers. But what makes them such a fuss for your vehicle’s needs?

Role of a Shock Absorber

Simply put, a shock absorber is a hydraulic device that absorbs impulses from your car’s suspension and spring. It reduces the recoiling factor that occurs when driving on a bumpy road.

Contrary to belief, a shock absorber doesn’t aid in weight support. It, however, is in charge of maintaining wheel contact on the road at all times. Your damper does this by resisting upward motion through viscous friction.

How shock absorbers work

In its basic form, a shock absorber works like an oil pump located between the wheels and the car frame. The upper mount of the damper joins to sprung weight (car shell supported by the springs) while the lower mount connects to the unsprung weight (wheel axle).

In the conventional twin-tube shock absorber (a design that features two tubes in the hydraulic fluid chamber), the upper mount contains a piston rod that is connected to a piston located inside the hydraulic fluid chamber. This chamber consists of a pressure tube (interior chamber) and a reserve tube (outer chamber).

During bumpy drives, the upper shock mount forces the piston rod down pushing the piston further in the pressure tube. The tiny opening in the pressure tube let out small amounts of hydraulic fluid under high pressure into the reserve tube. The resistant flow is what brings about the slowdown of the damper hence a stop in the spring oscillation.

A shock absorber thus converts the kinetic energy generated by your car's spring constant expanding and contracting into heat (thermal) energy. It then disposes of the heat energy to the atmosphere through heat exchange.

A shock absorber works in two cycles: compression and extension. During compression, the piston moves down while in extension state, it moves up the pressure tube. With that said, the compression cycle is in charge of the movement of your unsprung weight (wheel effects during a bump) while the extension cycle is left to handle the motion of the sprung weight (your car’s body).

Types of Shock absorbers

Today's shocks are design with motion-sensitive capability – how fast your spring action is and the resistance your shocks need to provide. This advancement makes shocks adjustable to different road conditions thereby controlling unwanted motions that result from bouncing, swaying, braking, and accelerating.

The types of shocks available also differ mostly in terms of design and application. They include:

How to identify a damaged shock absorber

After years of use, your shocks tend to wear out. When they do so, they are certain alarms that you need to watch out for, they include:

If your car is experiencing these indications, it might be time to replace your shock absorber with a new one.