While O-rings help you create seals on pipes, taps, machines and parts, there might be times when you need to take extra measures to get the most effective results. For example, you might want to use O-rings that have backup seals.
How do these seals work and why should you use them?
What Are Backup Seals?
O-rings help you create seals on parts that contain materials that could otherwise escape. For example, an O-ring can seal gaps around pipes that carry gases or liquids.
Backup seals are designed to work alongside O-rings. While O-rings are typically flexible and soft, their backup seals are usually more rigid and stiff.
These seals sit on one or both sides of an O-ring to give it extra support in difficult situations. They allow the O-ring to do its job as effectively as possible by holding it in place or by extending its sealing reach.
Why Use Backup O-Ring Seals?
While some O-rings work fine on their own, they sometimes work better with a backup seal. They might not be able to create a perfect seal in some configurations or under some working conditions.
For example, a sole O-ring solution works well when the ring simply has to seal a small extrusion gap. However, if this gap is bigger than the norm, then you might struggle to find an O-ring that is big enough for the application.
Here, you can give the O-ring some help to plug the gap completely. You can put a backup seal on one side of the ring, or on either side if you need to. The seals hold the O-ring securely in the right place and effectively gives it a wider area of coverage. So, you seal the gap more effectively.
O-rings also sometimes run into problems if they are put under regular or high levels of stress. For example, rings might move out of position if they have to deal with a lot of regular vibrations or pulsing movements. They might also struggle if they have to put up with lots of pressure or temperature changes.
If you add backup seals in these situations, then you strengthen the O-ring. The seal keeps it in the right position so that it can't move; it also absorbs some of the pressure in the area.
Like O-rings and other hydraulic seals, backup seals come in various sizes, shapes and materials. To find the right match for your job, ask your O-ring supplier for advice.