Compression gas springs

It is the simplest, most popular and the larges quantity of gas telescope produced. Normal, standard… etc. names also cover this type.
Normally open, compression needs strenght. It runs continuosly from end to end, restores to reset without load.

Size range:

Within the range shown in the table below, we produce compression gas springs , even in individual sizes.
The ends of the gas springs are threaded in principle, but can be chosen from a large variety of end fittings as required.


Type A B C Stroke x F1 max. D E
Rod Ø [mm] Cylinder Ø [mm] Stroke [mm] Basic lenght calculation [mm] Extended lenght calculation [mm]
FBA06 6 15 20 – 300 60 000 (C x2) +35 (C x2) +35 +G +H
FBA08 8 18 25 – 400 150 000 (C x2) +45 (C x2) +45 +G +H
FBA10 10 22 30 – 500 300 000 (C x2) +50 (C x2) +50 +G +H
FBA10/27 10 27 50 – 700 300 000 (C x2) +50 (C x2) +50 +G +H
FBA14 14 28 50 – 800 800 000 (C x2) +50 (C x2) +50 +G +H
FBA20 20 40 50 – 800 2 000 000 (C x2) +75 (C x2) +75 +G +H

For each type, the stroke and the maximum value of F1 are determined to avoid bending of the rod. If the gas spring you are looking for exceeds this value, it can only be made with a smaller stroke or force, or it can be made only from bigger type.

The value of G and H are different for each fitting type.

Force characteristics and dampering:

The force of the compression gas spring is not constant, depending on the position of the piston rod and the direction of movement. The force is required for compression is always greater than the extension froce of the gas spring.

Of the 4 different forces, only one can be definite, preferably the the smallest thrust, F1. This force is called as the force of the gas spring, this is indicated on the nameplate. The F2, F3, F4 force are indicative, may differ from the theoretical values. The force of the gas spring can be affacted by the ambient temperature. When fabricated, the F1 is measured at 20±2 °C. With the change of the temperature, the force change rate is about 3,3% for every 10 °C deviation.


Type P Fs max F1 Possible damperings
Progression Friction force max [N]. Smallest extension force [N] Extension Compression Both direction Without dampering
FBA06 1,30 30 30 – 400 X X X X
FBA08 1,35 30 50 – 800 X X X X
FBA10 1,40 35 50 – 1200 X X X X
FBA10/27 1,20 40 100 – 1200 X X X X
FBA14 1,50 50 250 – 2500 X X X X
FBA20 1,45 60 500 – 5000 X X X

During the damping of the gas springs, it is the stroke end damping, braking can be mean, which is slows down the speed of movement before reaching the entire open and/or closed lenght, thus saving the structure and the telescope. The compression gas springs can be ordered with normla or increased damping lenghts.

Function and structure:

The compression gas spring is a cylinder filled with high pressure nitrogen, which is divided by the piston rod into two interlocked internal chambers. The two sides of the piston, due to the different size surfaces, has differnt force of the gas charge, lower on the lower side than the top. The difference of the two forces is the force of the gas telescope,which pushes the rod outwards.

Parts of compression gas springs:
1, End fitting 2, Piston rod 3, Guiding element 4, Seal 5, Piston 6, Gas and lubrication 7, Cylinder


It is used in the automotive industry to open buses, cars, trailers, motorhomes, engine compartments, and luggage compartments. In the enginering industry it is used for heavier enclosures, for convenient handling, storing, serving and display cabinets, refrigerated counters, solariums and photocopiers, as well as all the equipment, devices where you want to use a component of the product to be user-friendly and convenient. In building engineering, it is used to facilitate the opertation of roof windows, awnings and ladders, cover sheets, cellar doors, and manhole covers. In furniture industry, opening and lifting of bed linens, beds, tables, or cupboards.


The Fedbaer gas springs can be ordered with the following appearances and materials

Fedbaer Basic series

Standard version, black rod and tube

Fedbaer Silver series

Chrome plated rod, silver metallic tube

Fedbaer Inox series

Stainless steel rod and tube



Accessories for Fedbaer gas springs

End fittings

List of optional fittings

Protective cover

Protect the rod from damage

Safety lock

Locks in open position


Operating temperature

The Fedbar gas springs can be ordered for the following temperature conditions:

Coldproof gas spring

max.: +80 °C
min.: -45 °C

Recommended below -20 °C

max.: +80 °C
min.: -30 °C

Recommended for normal use

max.: +200 °C
min.: -30 °C

Recommended above +80 °C