The trim8 mean wedge sealing surface overlaying 13Cr, not the whole wedge 13Cr. Just like the seat ring stellite, not the whole seat stellite material.Moreover, casting material code of 13Cr is CA15.
Bruce | https://www.ntgdvalve.com
another point need to concern, the work pressure is the one pipe work stably, but we need to consider instantaneous pressure, caused in the open or close process. So require a safety coefficient.
