Passivate before or after lap
Passivate before or after lap
(OP)
We are having a discussions as whether it is better to passivate before or after performing final Lap / Polish of a metal seat. Material 300 series CRES, min 8 finish.
we perform the lap in house but the part is machined and passivated prior to our reciept.
Is there any spec that stipulates this order?
Certainly using iron lap tools leads me to believe the Passivation would occur post lap.
we perform the lap in house but the part is machined and passivated prior to our reciept.
Is there any spec that stipulates this order?
Certainly using iron lap tools leads me to believe the Passivation would occur post lap.





RE: Passivate before or after lap
If it was my choice I would eliminate the initial passivation step.
RE: Passivate before or after lap
The passivation process after lapping will add a process that can harm the lapped seat if is not very carefully done and will add one more inspection stage after the passivation.
300 Series are by nature stainless steel and naturally create a thin passivated layer. Be sure that at the lapping process you do not embed metal particles that can corrode.
RE: Passivate before or after lap
= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.
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