Although not a major component of an automobile, the gas struts are still incredibly important. Like many things in life, you only notice them when they are not working properly, so it is worthwhile being are aware of what they are and what to do when they stop working.
Gas struts serve many different purposes and can be used for anything where you need to control the speed of movement. For automobiles, this is lifting/closing the tailgate or boot. We are able to lift this heavy piece of metal with very little force thanks to these struts, plus they can then lock in place so that you can easily access the boot area. They then also control the force with which the boot shuts, stopping any damage from occurring to the car.
How They Work
So, what are gas struts exactly? Essentially, it is a piston rod which slides in and out of a pressurized tube. The rod is attached to the piston so that the piston is controlled by the energy applied to the rod, which is where force will be applied to the spring. The piston pushes gas in the strut, which causes it to compress and holes in the piston allow gas to flow either side. The piston is contained in a housing tube, which is filled with compressed gas and completely sealed to prevent any loss of gas.
One way of looking at their design is to compare them to a bicycle pump. Gas is compressed by forcing the piston rod and piston into the cylinder, but the key difference is that a gas strut is completely sealed so there is no escape. This creates gas pressure (up to 170 times normal atmosphere pressure), which becomes stored energy.
Replacing Gas Struts
Gas struts are a superb way to lift and support different components, but they do have a lifespan. Usually, you will encounter a very gradual loss of gas pressure – this results in them being unable to support the weight. They can be re-gassed, but many motorists find it easier and more reliable to replace the struts. You can find the right struts for your particular vehicle at suppliers, like SGS. Many suppliers also provide simple to follow fitting instructions.
Gas struts are fantastic devices that often go unnoticed until they are not working properly. The next time you need to get something out the back of your car, take a moment to think about just how useful the struts are and how difficult it would be to access your boot without them.