What are compression gas spring?
Compression gas springs are versatile hydro-pneumatic (containing both gas and liquid) lifting mechanisms that help us raise, lower and support heavy or cumbersome objects more easily. They’re most widely seen in various configurations of door hardware, but the potential uses are near limitless. In everyday use, gas springs are now very commonly found in vehicle compartments, supporting adjustable chairs and tables, on all manner of easy-open hatches and panels, and even in small electronic devices. As the name suggests, these close assist gas springs rely on pressurised gas along with some oil-based lubricant to support or oppose a range of external forces. The compressed gas offers a controlled way of storing and releasing energy as smooth, cushioned movement, transferred via a sliding piston and rod.
Compression gas springs also commonly referred to as gas struts, rams or dampers, although some of these terms imply a specific set of gas spring components, configurations and intended uses. Technically speaking, a standard gas spring is used to support objects as they move, a gas damper is used to control or limit that motion, and a damped gas spring tends to handle a bit of both.
With this in mind, how exactly do gas struts and dampers work in practice? Which types are most appropriate in which roles, and what’s the ideal setup for the job you have in mind? In the sections below we’ll explore these and other questions about gas springs, starting with a closer look at how most lifts, struts and dampers function.
What are extension gas springs used for?
Given the myriad door types that benefit from gas spring applications, it’s no surprise that there are almost as many options for which sort of strut will fit which scenario.
Household, school or workplace doors usually incorporate some sort of traction or door care gas spring, to help them open easily under pressure but return quickly to a closed position when not in use. Conversely, cabinet doors and access hatches often require the exact opposite function, allowing considerable weight to be lifted easily, and remain fully open until manually pulled shut again.
In either scenario, a locking gas spring might also be useful, enabling the door to hold itself in place midway between fully open or closed. Certain doors - such as those with folding mechanisms - may even require a variable speed gas strut, to allow for smooth operation as different parts of the door move at different rates, and to dampen movement as partitions slide into one another. As with all such fixtures, the correct type of door gas struts to choose will depend entirely on what job you want them to do once mounted. Gaining a clear idea of the desired action and activation force is always the best place to start when figuring out which gas spring product will best suit your needs.
Gas springs for cars
Some cars will incorporate multiple sets of car spring damper into the design of their various hoods, panels and compartments, but by far the most common usage is in boot-lifting mechanisms. In particular, nearly all hatchbacks and estate cars will have gas struts affixed to the rear assembly, helping to lift, support and lower their heavy tailgates smoothly and effortlessly.
In fact, the action on most car spring damper is subtle enough that many drivers don’t realise they’re actually helping to raise the tailgate, as opposed to just holding it in place once it’s up. It’s easy to tell how much heavy lifting these fixtures do once they start to wear and degrade, though - especially with some estate-type rear doors, which can feel remarkably heavy if their gas struts are overdue for replacement.
Gas springs for chairs
The compression gas springs commonly used for office chairs are generally arranged in more of a ‘damping’ configuration, where greater resistance is met as the chair is lowered, and less as it’s raised. This cushions the downward movement of the seat when you’re in it, but allows it to spring back to its starting position with no manual force when empty.
Office chair gas struts are nearly always lockable one way or another, although it’s worth noting that the locking mechanism is sometimes entirely separate from the spring itself. In these cases, rather than being a built-in feature of the strut, the lockable component functions more like a quick-release clamp positioned around the sliding central column. Both types tend to be equally effective at holding a comfortable position, and are similarly easy to adjust for the user.
