E -7018 (TAPPER BURNING)

[Jignesh Desai]

Can anybody write some technical reasons behind tapper burning of subject electrodes with high fluctuations of current and wastage of excessive stub length because of red hot (@ 30%)?

 

Also with above, what could be the possible defects in the weld joints?

 

Regds/Jignesh

[manish kulkarni]

Dear Jignesh,   when electrode is manufacured, if the cake ( wet flux) is not concentic to core wire, this problem is possible.Hence you get problem like taper buring.Problem is weld- is porosity .   Better to replace. Regards,   Manish Kulkarni --- On Wed, 29/12/10, Jignesh Desai <jignesh....@gmail.com> wrote:

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[ESN]

Dear Jignesh,

 

The possible reasons are:

1)      Manufacturing defect i.e the flux coating and the core wire are not concentric that leads to excess coating at once side

2)      The core wire is not straightened properly in the manufacturing process.

3)      Influence of magnetic flux in the welding area which gives arc blow that gives a feeling of one-side burning.

 

Regards,

Shankar Narayan

 

 

From: material...@googlegroups.com [mailto:material...@googlegroups.com] On Behalf Of Jignesh Desai
Sent: Wednesday, December 29, 2010 8:33 PM
To: material...@googlegroups.com
Subject: [MW:8989] E -7018 (TAPPER BURNING)

 

Can anybody write some technical reasons behind tapper burning of subject electrodes with high fluctuations of current and wastage of excessive stub length because of red hot (@ 30%)?

 

Also with above, what could be the possible defects in the weld joints?

 

Regds/Jignesh

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[maghreb soudure]

Dear Jignesh

 

THis problem is due to bad quality of coating that can't support the continous energy to the limit and this makes difference between brands .I guess the problem appears most on hig alloyed electrodes .

 

Best regards

 

Moez

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