No registration or passwords; no pop-up ads -- just aloha, fun, & answers.
(as an eBay Partner & Amazon Affiliate earns from qualifying purchases).
Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Advertise
 
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

Aluminum tubing corrosion in stainless flange




My application is in a nuclear plant on the N-16 monitoring system. We have 6061-T6 aluminum tubing, 3/8-in OD, attached to a 316 stainless flange with a stainless male NPT Swagelok fitting. We are experiencing what appears to be galvanic corrosion right above the ferrule of the fitting. The tubing line is subjected to stagnant flows the majority of the time. If we used an aluminum fitting, would this just transfer our corrosion problem to a different area...perhaps the threads of the fitting, or is there a better solution. Using stainless tubing is not an option.

Rob Howard
Design Engineer - Idaho Falls, Idaho, USA
September 27, 2010



A few more details are necessary, but the starting point is that, yes, galvanic corrosion is a serious issue. I assume the aluminum is finished: hardcoated, perhaps, to give it wear resistance? An anodized finish will give it some electrical insulation, as well: the thicker, the better.

Any number of conditions can allow for electrical conductivity in this system, which allows for galvanic corrosion. Isolating them all would be like Hercules facing the Hydra! Therefore, your goal is to insure that all components are grounded in addition to being insulated.

Mike Burnson
- Chicago, Illinois, USA
October 9, 2010


Just a question: Would it be possible to use an ultra thin film corrosion preventative compound between the 6061 and the stainless steel. The CPC would have to be a non-harding "self-healing" cpc and have a high dialectric.

Larry Clark
- Brunswick, Georgia
October 11, 2010




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"