where expertise comes together - since 1996

Web's Largest Portal of Nondestructive Testing (NDT)
Open Access Database (Conference Proceedings, Articles, News), Exhibition, Forum, Network

All Forum Boards
Technical Discussions >
Cladding Question
Career Discussions
Job Offers
Job Seeks
Classified Ads
About NDT.net
Articles & News

Vidisco Ltd.
Vidisco Ltd. is the leading designer and manufacturer of state-of-the-art Digital Radiography systems.

707 views
20:13 Oct-20-2009
Mark
Cladding Question

Hi All,

Basically I have an interview on Friday and I know they are having a problem welding inconnel to carbon steel (I don't know the grades, but they are to be used off shore and sub sea), they are having up to 5% dilution problems with the inconnel.

Has anyone ever come across this or a similar problem?

It would be a good topic to talk about at the interview and i'm struggling to find anything from the web

Mark

 
20:44 Oct-20-2009

Roger Duwe

NDT Inspector, API-510, 570, 653
MISTRAS,
USA,
Joined Jan 2009
148
Re: Cladding Question In Reply to Mark at 20:13 Oct-20-2009 (Opening).

5% dilution sounds like a submerged-arc SAW overlay. A 'colder' weld process will decrease the dilution. I would try GMAW / MAG in the short-circuiting mode. It has the least penetration, and thus least dilution, of the common welding processes.

 
21:06 Oct-20-2009
Mark
Re: Cladding Question In Reply to Roger Duwe at 20:44 Oct-20-2009 .

Hi Roger,

Yeah they are using sub arc (I should have said before). They make sub surface christmas trees and apparently spent a fortune on getting 4 very expensive machines so I would imagine they will try like hell to make them viable.

I've only seen pictures of these christmas trees, so i'm not sure if they used MAG and then got these machines to help with the work load or had old sub arc machines there and replaced them.

Not used much sub arc, could polarity be a factor? ie using AC instead of DC?

 
15:40 Oct-21-2009

Roger Duwe

NDT Inspector, API-510, 570, 653
MISTRAS,
USA,
Joined Jan 2009
148
Re: Cladding Question In Reply to Mark at 21:06 Oct-20-2009 .

AC is an excellent idea. Hopefully, the new machines have that option.

SAW is run DC-Electrode Positive, putting the bulk of the heat on the wire [and flux pile]. Going to DC-Electrode Negative would put the bulk of the heat onto the base metal, a VERY bad idea. I expect that this would more than double the dilution rate.

 


© NDT.net - The Web's Largest Portal of Nondestructive Testing (NDT) ISSN 1435-4934

Open Access Database, |Conference Proceedings| |Articles| |News| |Exhibition| |Forum| |Professional Network|