Alkali-resistant O-ring
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The material contains alkalis; what material should be used for the O-ring in the mechanical seal?
This post was last edited by foam_ZPTK on 2018-1-5 at 12:29. EPDM is resistant to alkalis, but not to mineral oils； PTFE or PTFE-lined tubes could be considered; these two types of rings are just too hard
The question is: what base? What temperature? What concentration? ~~~~At room temperature, saturated NaOH poses no major problem for either EPDM or NBR ；
For ordinary alkaline liquids, EPDM-H is sufficient; however, in cases where the temperature is greater than 120°C and the concentration of caustic soda is greater than 40%, it is best to use perfluoroether (FFKM) rubber.
EPDM, AFLAS tetrafluoropropylene, KALREZ perfluoroether. Any of these alkali-resistant options will work; choose based on temperature and the specific material