Gas springs offer a reliable and long-lasting alternative to traditional mechanical springs. They are characterized by the use of a gas-filled cylinder. Gas springs use compressed gas — typically nitrogen — to exert a pushing or pull force via a piston. In addition to a gas-filled cylinder and piston, however, gas springs also contain seals.
What Are Gas Spring Seals?
Gas spring seals are components that isolate and prevent the stored gas from leaking. While available in different types, such as extension and compression, all gas springs feature a gas-filled cylinder; it’s what distinguishes them from mechanical springs.
Seals are used to maintain the cylinder pressure. They allow the piston to move in and out of the cylinder while simultaneously creating a barrier against leaks and environmental contaminants.
How Gas Spring Seals Work
Gas spring seals work by pressing against the piston rod to create an airtight mating surface. The piston rod moves in and out of the cylinder during usage. Without a seal, gas springs would lose pressure and, thus, no longer exert a pushing or pull force. The seal around the piston rod prevents this from happening by trapping gas within the cylinder.
In addition to gas, many gas springs contain oil. Oil is used to coat the seals, as well as the piston rod, so that the rubber remains pliable. At the same time, it helps to minimize friction while extending the lifespan of gas springs.
Common Types of Gas Spring Seals
Not all gas spring seals are the same. While they are designed to prevent leaks, they are available in different styles. Rod styles are the most common. They sit around the piston rod, allowing the piston rod to move without leaking gas.
Many gas springs feature piston seals. As the name suggests, they are found around the piston. Piston seals are located inside of the cylinder where they help to control damping.
There are also O-rings. O-rings, of course, are characterized by a ring-like shape. They are commonly found around shafts where they prevent gas and fluid from leaking.
How Long Do Gas Spring Seals Last?
Gas spring seals don’t last forever. Over time, they will degrade and lose their ability to protect against leaks.
With that said, high-quality gas spring seals last a very long time. Many of them will last for over five years or tens of thousands of spring cycles.