What is a gas spring?
Gas springs can be defined as hydro-pneumatic, energy storage elements. Nitrogen gas and oil are utilized for providing compressible and damping (motion control) mediums. Gas springs can be configured to meet a wide range of requirements.
Gas springs consist of a precision rod attached to a piston, moving within a sealed cylinder containing pressurized nitrogen gas and oil. Their force (F) is equal to the pressure differential (P) between internal and external (environment) pressures, acting on the cross-sectional area of the rod (A).
While for most applications ∆P (pressure differential) can be approximated by the spring’s internal pressure (P), ∆P must be taken into consideration for gas springs used in high-pressure environments (e.g. Sub-sea applications).
How do gas springs work?
As the piston rod is introduced into the cylinder (compression stroke), the internal gas volume decreases resulting in a proportional increase in pressure (Boyle’s Law). Consequently, the force of a gas spring is higher when the rod is compressed (see Figure 1).
The difference between the forces seen at the two extreme rod positions- named P1-force and P2-force respectively- is an important gas spring characteristic and called K-factor (IGS) or gas spring progression. When compared to mechanical springs, gas springs can achieve very low K-Factors, typically ranging from 1.05 to 1.8 (or %-80% progression). Unlike coil springs, gas springs are pre-loaded (pressurized) at the required P1-force which is available immediately.
For this reason, P1 force must be taken in account when calculating the force of a gas spring at a given position:
Where F is the force of a gas spring, k is the spring constant expressed in N/mm (force change per unit of compression) and X is the deflection distance in mm.
Figure 1- Gas Spring schematic - Pressure/ Volume vs. stroke diagram. As the piston moves from the fully extended position (P1) to the fully compressed position (P2), the pressure (solid line) rises and the volume (dashed line) reduces.
What is the difference between a gas spring and a regular spring?
Gas springs contain pressurized nitrogen gas and oil to create varying pressures. While a “regular spring,” typically referred to as a mechanical spring, uses physical deformation of a material to store potential energy. Picture a compressing coil spring, instead of the cylindrical gas springs. A gas spring is designed to offer a more consistent force output than mechanical springs. Using pressurized gas and oil, springs can create smoother or slower movements.
What are the parts of a gas spring?
The parts of a gas spring include a road, rod seal, nose bearing, piston and end plug. In addition to the pieces used to construct each gas spring, they are filled with pressurized nitrogen gas and a small amount of oil.
What are the different types of gas springs?
When exploring solutions for motion control, it's clear that not all applications are the same, which is why a diverse range of gas springs—also known as gas struts or gas shocks—is essential. As a premier manufacturer, Industrial Gas Springs offers a comprehensive lineup designed to meet any challenge. The primary types available include versatile compression gas springs, safety shroud gas springs, adjustable locking springs, stainless steel gas springs, specialized tension gas springs, and smooth-motion dampers. This selection of standard, in-stock products ensures that solutions are readily available for a wide variety of common applications.
Beyond the standard offerings, true innovation lies in customization. Industrial Gas Springs excels in creating custom spring solutions. The dedicated engineering staff assists with the design and engineering of custom gas springs tailored to meet exact specifications. This allows for an impressive array of specialized features, such as a reduced compression ratio for unique force requirements, high-temperature seals for harsh environments, and food-grade oil fill for sanitary applications. Furthermore, options for high-speed extension, low-friction operation, and custom sizing ensure the final product is a perfect fit. To complete the package, a full line of mounting hardware, including various end fittings, brackets, and ball studs, is available to ensure seamless integration of the gas springs into any product or application. Contact Industrial Gas Springs today to find the right gas springs for your application today.