TECHNET Archives

January 2001

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Brian Ellis <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Wed, 3 Jan 2001 10:11:47 +0200
Content-Type:
text/plain
Parts/Attachments:
text/plain (63 lines)
Barry

Assuming you start with tap water, a single stage RO removes about 90 -
95% of the impurities with good membranes, so, typically, a 500 uS-cm
water will come out with a conductivity of about 35 uS-cm and a double
stage RO about 2 - 3 uS-cm. This would be adequate for most W/S
flux/paste removal. An adequately designed double-bed DI purification
will produce water with a conductivity of typically 0.3 - 1 uS-cm which
is usually perfect for the job. A mixed bed DI system, often used for
polishing double bed systems, will produce down to 0.056 uS-cm, which is
almost too good and can attack stainless steel welds if the flux is
halide-activated! What you choose depends on a) how much water you need
b) the purity you need and c) whether you recycle it in a closed loop.
In the latter case, more precautions are necessary for successful
operation.

In many cases of small requirements (< 100 l/day) in open circuit,
provided a reasonable quality tap water is available, a single mixed bed
system is often used. The capital costs are very low but the running
costs are higher. If the tap water contains dissolved iron or some other
impurities, you cannot run RO without a pre-treatment, otherwise the
membranes will clog.

If you care to e-mail me privately, I can guide you further as to the
best choice of system, telling me the details of your equipment and
process.

My recommendation regarding temps is 50°C for the wash (WARNING! a
higher temp may result in insoluble residues with many W/S systems) and
somewhat higher, progressively, for rinsing.

HNY

Brian

> Barry Gallegos wrote:
>
> Happy New Years Netters.
>
> What is the difference between RO water and DI Water and Is RO only a
> viable option for a Water Soluble process only.
>
> Also am wondering what would be a standard wash and rinse temp to use.
>
> Thank you in advance.
>
> Barry Gallegos, PE
> Western Electronics, LLC
> 110 E. 43rd st. Boise, ID. 83714
> P-208-377-1557
> F-208-377-9836
>

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
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 delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------

ATOM RSS1 RSS2