The required spring force is calculated by putting the actual values in the following formula :
F1 = ( ( (X x Y) / (2 N Z) )+ 5 ) x 9.81 = Gas spring pressure in Newtons
F1 = spring force
N = quantity of gas springs needed
X = weight of moving part
Y = length of moving part
Z = distance (in meters) from fixation point of the gas spring on the moving part to the axis of rotation of the moving part (pivoting point on moving part).
The value 5 = the force of 5 Kg/p engendered by the constant friction movements.
Example:
For a moving part with the following values :
N=2
X = 50 kg
Y = 1,50 m
Z = 0,25 m
F1 = ( ( (50 x 1,5) / (2 x 2 x 0,25) )+ 5 ) x 9.81 = 784,8N
In this case the margin of tolerance being +/- 30 N, we recommend two gas springs of 810 N
2 - Other spring dimension
The stroke and the diameter of the gas spring are chosen with regards to the required distance between the point of fixation of the gas spring on the moving part and the point of fixation of the gas spring on the fixed part.
The stroke is directly related to the angle of rotation of the moving part.
For an opening of 90°, we generally recommend the following ratio :
(Stroke / Z) = (1 / 0,8)
3 - Once all the dimensions have been determined you can find the gas spring reference you need by checking it in our catalog.
4 - Important recommendations :
Always install in a vertical position with piston rod pointing down
