Encapsulated O-ring contains a silicone or Viton O-ring inside and the thin FEP or PFA covered outside, so Encapsulated O-ring has the elasticity and tightness of the rubber and the chemical resistance of the PTFE. And Encapsulated O-ring also has the excellent sealing property. Rubber O-rings are easy to abrasion, and not good resistance to chemical and gas permeation. PTFE O-rings are hard that can resist to compression but less elastic.
FEP/PFA Encapsulated O-rings have good resistance to swelling and chemical stability (unless attack by alkali metals, fluorine and some halides at high temperatures) with good resilience. FEP/ PFA Encapsulated O-rings have a very low coefficient of friction (only 0.1 to 0.2) and excellent resistance to gas permeation. These properties allow Encapsulated O-rings to be used in harsh environments. |