Re: [PipingDesign] which one is better to use SS studs or LAS studs

From: <bbullough@foth.com>
Date: Wed Jan 30 2008 - 08:58:00 EST

Ashok Yargol (if that is your name):

you do not supply much detail regarding service (process chemistry, pressure, temperature, etc.), but in general, SS bolts (studs) and nuts are more brittle, much more prone to galling, and in gnerlamore difficult to use. Regardless of which you decide to use, you must (and this is an absolute MUST) use insulators (sometimes called isolators) to prevent galvanic corrosion. This means insulating washers and sleeves around the studs or bolts. Then, care must be taken in tightening the nuts to prevent damaging the insulator washers and sleeves. This therefore means that the washer material must be selected with care and consideration of its mechanical properties. This is all very common practice in the underground and underwater pipeline industry.

Also, next post, please identify yourself, not just your question!

... Bruce D. Bullough ...
Lead Process Engineer
Foth Production Systems, LLC
8550 Hudson Boulevard North, Suite 100
Lake Elmo, MN 55042
Direct: +651-288-8598 Fax: +651-288-8551 http://www.foth.com

IMPORTANT NOTICE
This communication including any attachments, (E-mail) is confidential and may be proprietary, privileged or otherwise protected from disclosure. If you are not the intended recipient, please notify the sender, permanently delete this E-mail from your system and destroy any copies. Any use of the E-mail, including disclosure, distribution or replication, by someone other than its intended recipient is prohibited.

This E-mail has the potential to have been altered or corrupted due to transmission or conversion. It may not be appropriate to rely upon this E-mail in the same manner as hard copy materials bearing the author's original signature or seal.

"ashok_yargol2000" <ashok_yargol2000@yahoo.com> Sent by: PipingDesign@yahoogroups.com
01/29/2008 09:47 PM
Please respond to
PipingDesign@yahoogroups.com

To
PipingDesign@yahoogroups.com
cc

Subject
[PipingDesign] which one is better to use SS studs or LAS studs

here is a heat exchanger u-tye at the flange joint are of two material one is SS and other is low Alloy steel and for this joint we use studs, which one will be better either using SS studs or LAS studs as here the corrosion rate is high Received on Wed Jan 30 08:58:00 2008

This archive was generated by hypermail 2.1.8 : Tue Mar 09 2010 - 00:21:23 EST