Gas Struts
Gas Springs for Industry, Mechanical Engineering and Vehicle Applications
Gas springs support controlled linear movements and are used to open, close, lift, lower, hold or position movable components. Typical applications include flaps, hoods, doors, covers, machine guards, furniture, vehicle components, medical equipment and technical devices.
Febrotec offers gas compression springs in numerous sizes and force ratings as well as traction gas springs, locking gas springs and matching accessories. Many standard versions are available directly from stock.
The correct gas spring is selected primarily according to extended length, stroke, required force, direction of movement and mounting points.
Which Gas Spring Is the Right One?
Gas Compression Springs with Threaded Connections
Conventional gas compression springs generate an extending force. They can support the lifting of a flap and partially or completely counterbalance its weight.
Our gas compression springs with threaded connections can be combined with different end fittings and mounting components. This allows flexible adaptation to the respective design.
Selection is based mainly on extended length, stroke, force and connection thread.
Gas Compression Springs with Welded Eyes
Gas compression springs with welded eye ends already have permanently integrated mounting eyes.
This version is particularly suitable where interchangeable end fittings are not required and a compact, ready-to-install connection is preferred. In addition to length, stroke and force, the eye dimensions must also be considered.
Traction Gas Springs
While a gas compression spring extends the piston rod automatically, a traction gas spring works in the opposite direction: the piston rod is pulled into the cylinder.
Traction gas springs are therefore suitable for designs that require a pulling force or where the available installation space does not permit the use of a conventional gas compression spring.
Locking Gas Springs
Locking gas springs not only support movement but can also be locked in a selected position.
They are used, for example, in adjustable seats, work surfaces, control panels, medical equipment and other height- or angle-adjustable constructions.
A suitable release system is required to unlock the gas spring.
End Fittings and Mounting Components
The gas spring should be connected to the surrounding structure so that it can move freely and without unnecessary stress. Various gas spring end fittings, such as rod eyes, clevises and ball sockets, are available for this purpose.
Matching gas spring mounting brackets allow connection to flaps, frames, housings and other components.
Ball joints can compensate for small angular misalignments during movement and are therefore particularly suitable for many applications.
For applications where an extended gas spring must be protected against unintended compression, locking tubes are available as a mechanical safety device.
How to Select the Correct Gas Spring
The following information should be known for an initial selection:
-
Extended length: Distance between the mounting points when the construction is fully open.
-
Stroke: Distance travelled by the piston rod between the retracted and extended positions.
-
Required force: The force depends on the weight, centre of gravity, lever arms and number of gas springs used.
-
Connection type: Threaded ends, eyes, ball joints or other fittings must match the design.
-
Installation position: The position of the mounting points has a major influence on the force curve and movement.
-
Operating conditions: Temperature, humidity, dirt and chemical media must be taken into account.
When replacing an existing gas spring, important information can often be found directly on the cylinder. Particularly useful are the extended length, stroke, force rating in Newtons and connection dimensions.
The force rating alone is not sufficient. Two gas springs with the same force can behave very differently if their lengths, strokes or mounting points are different.
Installation Recommendations
Gas compression springs should be installed without unnecessary lateral forces acting on the piston rod. Misalignment or permanent radial loads may stress the guide and sealing system.
For conventional gas compression springs, an installation position with the piston rod pointing downwards is advantageous in many applications. This helps keep the internal oil in the area of the seal and guide.
The piston rod should remain clean and free from damage. It must not be gripped with pliers, scratched, painted or otherwise mechanically damaged.
The full available stroke should not be used as the mechanical end stop of the application. Separate stops can prevent unnecessary loading of the gas spring and mounting components.
Selecting a Gas Spring as a Replacement Part
For vehicles, machines or older equipment, the original gas spring cannot always be identified clearly. Selection based on technical data is therefore often more reliable than using the machine or vehicle designation alone.
Check or measure:
-
fully extended length,
-
stroke,
-
piston rod and cylinder diameter,
-
force in Newtons,
-
connection thread or existing end fittings.
If an identical version is no longer available, a technically suitable alternative may be possible depending on the design.
Safety When Handling Gas Springs
Gas springs are pressurised components. They must not be opened, drilled, heated or mechanically modified.
A gas spring with significant loss of force, a damaged piston rod or a leaking cylinder should be replaced. Repair or refilling attempts should not be carried out without suitable technical equipment.
Gas and lubricants remain inside the cylinder, so defective gas springs must also be disposed of correctly.
Frequently Asked Questions About Gas Springs
What force do I need?
The required force depends not only on the weight of the flap but also on its centre of gravity, lever arm, mounting points and the number of gas springs used.
Can I use a gas spring with a slightly different length?
This may be possible, but it changes the opening angle and movement. Installation space and mounting points must be checked first.
What does the force rating in Newtons mean?
It describes the extending or pulling force of the gas spring. As a rough guide, 100 N corresponds to the weight force of approximately 10 kg.
Why does a gas spring lose force?
Over time, gas may gradually escape through the sealing system. As the internal pressure decreases, the spring force is reduced.
Which gas spring do I need for my application?
Our technical team can support you with the selection. A drawing or photo of the installation situation together with information on weight, dimensions, stroke, mounting points and the desired movement is particularly helpful.
Further information on function, selection and installation can be found in our gas spring FAQ.