Dave:
                For wave soldering and reflow oven  the 99.5 % would be more
than necessary. Ambient air which is about 40 percent O2 is all around the
machine and very quickly will mix with the injected N2. If it was for a
close chamber such as it is used on semiconductor fabs, then it would make a
difference if O2 was not desirable in a particular process. Your decision
should be based on what is more economical.
        Regards,
        Ramon

> -----Original Message-----
> From: Dave Hillman [SMTP:[log in to unmask]]
> Sent: Tuesday, March 09, 2004 1:00 PM
> To:   [log in to unmask]
> Subject:      [TN] Nitrogen Purity Question/Survey
>
> Hi folks! Question for those folks using nitrogen for an inert atmosphere
> in their reflow processes or as a blanket gas on their wave solder
> processes. Cryogenic nitrogen is typically 99.998% purity (in terms of O2
> content). On-site nitrogen generation equipment can deliver N2 gas ranging
> from 99.5% to 99.99% purity (again, in terms of O2 content). What gas
> purity level are you using in your processes and do you have a rationale
> for selecting that purity level?  The reason for the question is that I am
> involved in an exercise of comparing on-site nitrogen generation versus
> cryogenic nitrogen supplies.
>
> Thanks in advance for you assistance.
>
> Dave Hillman
> Rockwell Collins
> [log in to unmask]
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e
> 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
847-509-9700 ext.5315
> -----------------------------------------------------

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
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 847-509-9700 ext.5315
-----------------------------------------------------