Thanks for the information. I am familiar with alkaline ammonium sulfate 
  etchant and how SS survives incredibly well in this environment. In 
fact SS 316 is used as an inert anode when electrowinning from this 
solution.  As Brian also pointed out the corrosiveness of chloride ions 
towards SS, I think a new and better pump will save me headaches later on.

Adam


Mike Fenner wrote:
> Long ago in another life I was involved with PCB Fab machines. Our etching
> systems used Titanium whenever metal parts were to be exposed to etchant.
> Pumps though would have been impossibly expensive in titanium, they were
> made of polymer or polymer coated SS. Any metal parts that could not be so
> coated were made of SS and designed to be easily replaced in routine
> servicing. Overall the designs specifically went out of their way to avoid
> this, especially fixings, even if it meant that the pumps were less
> efficient than they otherwise could have been. 
> 
> 
> Regards 
> 
> Mike

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------