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Dwell Time Before Seal Test?

Is there a standard dwell time anodizers wait after completion of seal and rinse before performing the seal test (nitric/black dye)? Our current procedures specify a 5-24 hour wait time, which is quite inconvenient from a lean manufacturing perspective, but I can't find where that came from. Was just wondering what others' practice/procedures were.

Thanks,

Wayne VanTassell
metal finishing - Salt Lake City, Utah
2006

I presume you are using conventional HOT sealing, in that case there is no dwelling time - you can conduct your test after the process. On the other hand if you are using cold sealing then you may have to as per the recommendation of the chemical supplier. Hope this answers to your question.

Srimay Basu
Dubai Aluminium - Dubai, U.A.E.
2006

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After sealing, there is no dwell time before testing except to cool to room temperature. Some dye may need time to reach peak stability, especially if cold sealed.
Your best resolve would be to discuss with the client for the reason, if any, behind 5-24 hour wait in the procedure.

Kas Amadi
- Dayton, Ohio
2006

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The practice with the wait time was inherited, so I don't have the originator to ask, but we have begun performing the seal test immediately after the parts cool, with very good results.

Thanks for the feedback.

Wayne VanTassell
- Salt Lake City, UT, USA
2006