The Gaslift® spring consists of a cylinder, piston and rod assembly able to extend and contract telescopically.
The cylinder is filled with nitrogen gas at a very high pressure. It is this gas pressure which creates the lifting ability of the Gaslift® and the force exerted is proportional to the gas pressure.
A measured quantity of oil inside the Gaslift® lubricates the piston assembly and provides damping at the end of the extension movement. The damping imparts a more gentle action to the object being moved. Therefore, the Gaslift® should always be mounted with the rod in a downward position, when the door is fully opened.
|CALCULATING THE FORCE (F1)||DIAGRAM OF TYPICAL APPLICATION|
Calculating the force required to hold the lid in the Open position.
Refer to the diagram:
F1 – Force exerted by Gaslift® in Fully Extended Condition
U – Upper Mounting PointL – Lower Mounting Point
If the position of the CG of the lid is not known, then a spring balance or similar can be used to measure the force required to hold the door open.
If the force is measured at the upper mounting point U this force plus 10 – 15% safety factor is the F1 required. If the force is measured at any other point, use the perpendicular distance from the pivot point P to the attachment point of the spring balance as A and the spring balance reading as W in the formula.
GASLIFT APPLICATION (A SELECTION OF EXAMPLES)