What is that pad that comes behind an O-ring like this called?
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This post was last edited by zhangke668 on 2021-12-4 at 18:53. What is the name of that pad that comes after an O-ring like this? What is its function, and what is its typical material?
In English, this is called a back ring; we refer to it as a back ring as well. It is usually made of polytetrafluoroethylene (used in natural gas compressors) and serves to prevent the O-ring from being pushed out by high pressure. Refer to Appendix II of GB1235__O-ring Seals for more details
This should be called a guide ring, which serves a guiding purpose.
Thank you, big bro. What material is this usually made of?
I’m not sure of the exact name; search for “tetrafluoro wear-resistant guide ring” on Taobao, where similar terms can be found, and choose according to your needs. For reference.
The domestic standard term is anti-extrusion ring or retaining ring, while it is commonly referred to as back ring or open ring in practice. It is more commonly used in foreign products; no such standard has been found in China. It was not until 2020 that a standard was finally established.
The retaining ring is primarily used to prevent the O-ring from being squeezed into the sealing gap； The material is usually PTFE; when installing, care must be taken to ensure the correct pressure direction, as it must not be installed in the wrong way.