Conditions and Recommendations

Definitions and recommendations for use of BM Gas springs

Important information Please read carefully

A gas spring is not a security device

1- Dimension and pressure units

All dimensions are shown in millimetres (mm), all pressures/ forces in Newtons (N / F1) and all temperatures are in degrees Celsius (C°).

2- Installation conditions

The devices MUST be mounted with the rod facing downwards (with a minimum incline of 15°);

for horizontal installation or with rod dacing upwards, please contact us.

  • The gas springs must not be under any lateral pressure.
  • Warning: for devices with a welded clevis of between 0.5 and 1mm.
  • In the event of particle release, be sure to protect the rod.
  • If possible, avoid using the device at the maximum calibration.
  • If the device is to be painted, protect the completely. Do not use solvents to clean the rod.
  • The attachment points should be in line. There should be some margin allowed so that the rod is not put under lateral pressure.
  • Avoid all impacts on the gas spring.
  • Never take a gas spring apart: pressurised gas.
  • Do not allow any point to get on the piston / rod as this may cause a gas leak.


3- Installation warnings

Protect the rod against impacts, electric arc flashes, grinding sparks, paint and corrosive products. Do not tighten the rods with pliers or in a clamp without using protective lead, aluminium or copper grips.

4- Conditions of use

Number of returns / minute: maximum 5. For a higher rate, please contact us.

  • Endurance level: 30000 cycles. Loss of durability after cycles: maximum 15% (the endurance level varies according to the stroke length and calibration).
  • Working temperature: from -30°C to +80°C (at maximum stroke).
  • Recommended working temperature: +20°C output force variation due to temperature: 1% per 3°C.

5- Storage conditions before use

  • For a maximum duration of three months, the devices may be stored horizontally, in an ambient temperature.
  • For a longer storage time, or in a hot country, store them vertically, with the rod facing down.

6- Guarantee

  • 1 year starting form the date marked on the device. Example of date marking: 1011 (10th week of 2011).
  • For the guarentee to remain, if the device is to be repainted the manufacturing date must remain visible.

7- Neutralization

Gas springs hold a pressure of between 20 and 250 bar, and so it is necessary to release the gas before disposal. For your safety, please adhere to the following procedure:

  • Grip the tube lightly in a clamp
  • Split the tube at right angles to the axis in an area of between 30 and 35mm from the base of the tube.

To carry this out:

  • It is essential to wear safety glasses.
  • Use a metal handsaw
  • Place a cloth over the blade
  • As soon as a whistling sound is heard, stop sawing.
  • The gas removal will be complete when the rode can easily be moved by hand.

8- Tolerance margins

Force in Newtons   Margin of tolerance
50 < N < 250   + ou - 20 N
250 < N < 750   + ou - 30 N
750 < N   + ou - 40 N


1 rue de la gravière
(France metropolitaine)
Phone : 0033.(0)
Fax : 0033.(0)
EMail :

Berthold Marx

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