本SAE航空航天推荐规程（ARP）概述了液压和气动流体动力应用中各种类型的聚四氟乙烯（PTFE和TFE）支承环，包括它们的优缺点。

This SAE Aerospace Recommended Practice (ARP) provides an overview of the various types of polytetrafluoroethylene (PTFE and TFE) back up rings for hydraulic and pneumatic fluid power applications, including their advantages and disadvantages.