12. Materials of the Wetted Parts

The materials of the wetted parts depend on the purpose. SUS and PEEK have high pressure resistance and are used for highly pressurized parts. SUS is superior to PEEK in terms of pressure resistance, however, PEEK can be more easily bent and this enables easy handling. PEEK is also used when contamination of metal ions should be avoided. For weakly pressurized parts, PTFE is used because of the excellent chemical resistance.

SUS: Steel special Use Stainless, defined in Japanese Industrial Standards (JIS). SUS316 is widely used for wetted parts in HPLC.
PEEK: Polyetheretherketone
PTFE: polytetrafluoroethylene