# How do I find a replacement gas spring?

Before you try to find a replacement gas spring type it is necessary to find out how strong the ‘old’ gas strut or gas springs are.

Usually there is printed information on the gas spring (or on a label affixed to the housing) in which something is reported such as…. N.
The ‘N’ stands for Newton and the numbers that are in front then represent the number of Newtons.

For example:
300 N = 300 Newton
0300 N = 300 Newton

Once you know how strong (how many newtons) the gas springs must be, you can proceed to Step 1.

Step 1. With the ‘old’ gas strut measure: (Note: in millimeters!)

• the thickness of the rod (the thin part)
• the thickness of the housing (the thick part)

We sell the following types of gas spring:

Type       thickness of rod      thickness of housing
4-12             4mm                  12mm
6-15             6mm                  15mm
8-19            8mm                  19mm
10-23        10mm                  23mm
14-28        14mm                  28mm

• Choose a replacement gas strut type from this table that comes closest to the just-measured thickness of the rod and the thickness of the cylinder.

# Note down for the replacement gas spring: ‘gas spring type =  … –  … ‘

It may be that you can unscrew the attachment (screw eye, ball head, etc.) of the ‘old’ gas strut, at one or both ends. In so far that you want to reuse those make sure that the screw thread size matches the screw thread size of the replacement gas spring type.

You can check this as follows:

• On our website click on the tab ‘Configurator’ and choose a gas spring of the replacement gas spring type in the middle column (the length is unimportant at this time).
• Choose ‘None’ in the left and right column.
• Move the mouse/ cursor over the gas spring so that information is displayed about the screw threads that are on both ends of the gas spring.

You can select end fittings which you have to buy new, in the left and/or right column.•

• Move the mouse cursor over the selected connection so that a dimensional drawing of it is displayed.
• This way, you can check whether the end fittings can be suitably mounted in the existing gas spring application.

If it appears that the connections will not be a problem, you can proceed with Step 2.

Step 2. Measure the maximum length of the ‘old’ gas spring

For instance if we open a cover completely, then the gas spring extends completely into its maximum length. We must now determine this maximum length, measured center-to-center:

• fully open the cover and measure the distance from the centre of one end fitting to the centre of the other end Fitting

Write down for the replacement gas spring: ‘Length ‘max’ = …… mm.’

Step 3. Measure the shortest length of the ‘old’ gas spring.

If we close the cover , the gas strut is pushed in to a certain length. It is almost never the case that the gas spring is then completely (until the end of its stroke length) pushed in. A piece of unused stroke length is almost always left over. By taking into account this fact we are more likely to find a suitable gas spring (in terms of length) as a replacement for the ‘old’ gas strut. Therefore determine, with the ‘old’ gas spring still mounted, the shortest occurring centre to centre distance between the end fitting of the gas spring:

• Close the cover and measure the distance from the centre of one end fitting to the centre of the other end fitting of the ‘old’ gas spring.

If this measurement, however, is not feasible because, for example, the space under or behind the cover is insufficient to measure there, you can read below how you can determine the shortest occurring centre to centre distance:

• Open the cover or the hatch.
• Tie a thin rope tightly around the rod (the thin part of the gas spring).
• Move the rope until it is against the cylinder (the thick part of the gas spring).
• Close the cover or the hatch so that the gas spring gets its shortest occurring length.
• Open the cover or the hatch completely and measure the distance between the moved rope up to against the cylinder.
• Subtract this measurement from the previously measured ‘Length ‘max’’.

# Write down for the replacement gas spring: ‘Length ‘in’ = …… mm.’

The replacement gas spring must, when fully retracted, measured centre to centre between the connections, be able to become a bit shorter than the ‘Length ‘in’’ value found.

Step 4. Choosing the most suitable stroke length for the replacement type gas spring:

• On our website click on the tab ‘Configurator’ and choose a gas spring of the replacement gas spring type in the middle column (the length is unimportant at this time).

When you are re-using an already existing attachment at one or both ends, proceed with step 5.

• Choose the new end fittings to apply in the left and right column (the maximum centre to centre measurement between connection is shown)
• Push the gas spring in completely with the mouse/cursor in order to read the shortest possible centre to centre measurement
• In the middle column choose a stroke length that is as close as possible to ‘Length ‘in’ from below, that is associated with the replacement gas spring type.

Now compare the extendend lenght of the selected gas strut with the previously measured ‘Length ‘max’’ and assess the result of this with a possible difference in length (cover opens slightly less far or slightly farther).

If this seems acceptable then you have  succeeded in your attempt to find a replacement gas spring!

Posted in: Configurator