Notes on the use of gas springs


1. What is the role of gas springs?
Gas spring is an industrial accessory that can play the functions of support, cushioning, braking, height adjustment and angle adjustment, etc. In construction machinery, it is mainly used in the cover, door and other parts. It consists of the following parts: pressure cylinder, piston rod, piston, sealing guide sleeve, filling (inert gas or oil-gas mixture), in-cylinder control element and out-cylinder control element (meaning controllable gas spring) and joint, etc.

2. What is the working principle of gas springs?
The working principle of gas spring is to fill the closed pressure cylinder with inert gas or oil-gas mixture, so that the pressure inside the chamber is several times or tens of times higher than the atmospheric pressure, and the piston rod’s cross-sectional area is smaller than the piston’s cross-sectional area, thus creating a pressure difference to achieve the movement of the piston rod.
Due to the fundamental difference in principle, gas springs have significant advantages over ordinary springs: the speed is relatively slow, the dynamic force does not vary much, and it is easy to control. The disadvantage is that the relative volume is not as small as the coil spring, and the cost is high and the life is relatively short.
3. What should I pay attention to when using gas springs?
3.1 Because of the harsh environment of construction machinery, the sealing of the gas spring is required to be high, and dust and other debris should be avoided to enter the gas spring when it is used. In addition, prevent sharp tools from scratching or damaging the surface of the gas spring piston rod, and do not apply paint and corrosive chemicals to the piston rod.
3.2 The gas spring stroke should be added to the working stroke with a certain margin (about 10 mm) to avoid errors due to the installation process, which can affect the life of the gas spring and its use performance.
3.3 Gas springs configured in construction machinery generally have a short service life due to the outdoor environment, and should be considered in the design.
3.4 The ambient temperature range of gas springs is generally -35~+60℃.
3.5 The gas spring cannot withstand lateral or oblique forces during operation, otherwise the phenomenon of deflection wear will occur, leading to early failure of the gas spring, which should also be considered in the design.
3.6 For door structures with lighter mass and no latching device, the design should ensure that after the door is closed, the line between the fixed support point of the gas spring and the movable support point passes through the center of rotation to ensure that the elasticity of the gas spring can close the door tightly, otherwise the gas spring will often push the door open; for door structures with heavier mass (the hood of the machine), it is better to equip a latching device.
3.7 The gas spring cannot have relative motion when it is in the closed and working state, and its continuous expansion and contraction should be controlled within the required range.
3.8 The door structure of construction machinery (such as the hood of the machine) is generally heavy. When choosing gas springs, gas springs with safety devices should be considered to avoid safety hazards due to the failure of gas springs.
3.9 The gas spring should not be used as a limiting device, additional limiting devices are required, and rubber heads are generally used for limiting.