From: Hegde, Gireesh [mailto:Gireesh.Hegde@petrofac.com]
Sent: Wednesday, April 08, 2009 10:22 AM
To: materials-welding@googlegroups.com
Subject: RE: 1889] RE: 1881] Welding of Magnetised material
The first and easiest way is to weld this material with the SMAW (stick) process with AC POLARITY and use an AC welding rod. Secondly, attach the work clamp as CLOSE AS POSSIBLE as possible to the welding joint. Use good judgment not to damage or overheat the clamp. Third attempt would be to MINIMISE CURRENT and reduce the diameter of the welding rod. This will require welding the project with an increased number of passes. Last try would be to TIGHTLY WRAP the material to be welded with the work cable. Keep the wraps tight and use a clockwise rotation, the more wraps you put on, the stronger the magnetic field you will generate. The magnetic field you create by wrapping the work cable should generate a counter magnetic force which will hopefully reduce your welding problem. If the magnetic field problem increases, wrap the material to be welded using a counter clockwise rotation.
Another last solution is to BUILD/BUY the special equipment -Refer to link <http://www.patentstorm.us/patents/5345058/fulltext.html> http://www.patentstorm.us/patents/5345058/fulltext.html related to equipment which nullifies the magnetic field with US Patent 5345058 - Magnetic field negating system for weldments.
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From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Bathula Raghuram (Mumbai - PIPING)
Sent: 08 April, 2009 08:37
To: materials-welding@googlegroups.com
Subject: [MW:1889] RE: 1881] Welding of Magnetised material
Dear Fernando
In my opinion it is not possible to weld with a magnetic field strength of 60G.
FYI field strength required for Magnetic particle testing it should be 30G-60G, and as far as I know for welding it should be less than 3G
If you can able to achieve in any way please share your experience here for our knowledge
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From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of kataiah@bilfal.com
Sent: Sunday, April 05, 2009 1:07 PM
To: materials-welding@googlegroups.com
Subject: [MW:1881] Welding of Magnetised material
Hi,
Preheating the material upto certain temperature(dempends on material) will reduce residual magnetism in the material.
This will reduce the Arc blow problem & can be welded with conventional methods.
Regards
P.K
K.S.A
"ashish bhate" <ashishbhate22@gmail.com>
Sent by: materials-welding@googlegroups.com
04/04/2009 12:29 م
Please respond to materials-welding
To: <materials-welding@googlegroups.com>
cc:
Subject: [MW:1875] Re: [MW:1865]
HI !.
One of the way to reduce the effect of magnetic perturbation is to use AC welding machine.
On Fri, Apr 3, 2009 at 8:29 AM, Fernando <fernando@grupolabmat.com.br> wrote:
Dear all,
My name is Fernando, marine engineer from Brazil and, next week, I will have to develop a welding procedure in carbon steel in a closed ambient with magnetic field of 60 Gauss.
Do you have some tip / information about how would be possible minimize the effects of this magnetic perturbation?
Thanks
Fernando
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