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[MW:2953] Re: Weld Crack at Root trough weld metal

By Materials & Welding
I fully agree, only 3.2mm dia low hydrogen electrodes should be used for the root pass, minimum pre heat should be 100 dec C max interpass temp should be 150 deg C maintained throughout the welding cycle, cellulosic electrodes should never be used on sour service,
 
 
Nick Davies
Quality Engineer
Damaq Ltd
 
 
 


 
On Mon, Aug 17, 2009 at 12:00 PM, kayvan alyari <k.alyari@gmail.com> wrote:
Dear Friend
 
If the welding rate is not important for you, It is recommended to use E7016-G electrode for root pass to avoid cold cracking. As you know, E8010 is an cellulosic electrode and shall not be used in sour services. It has the high risk of hydrogen cracking!
 
Yours truly
Keyvan

 
On 7/21/09, shiva <luvshiv2002@gmail.com> wrote:

We are using API 5L X65 grade material for sour environment. With
reference to our WPS we used (Ador electrodes) e 8010 for root and
8018 for hot fill pass.
We took NDT and its okay. But after 1 month 4 weld joints crack. We
checked the macro hardness for existing and cracked joint . There was
a high hardness eg 351, 329 on root and in weld metal cap side 280
above. Which is very high.

Can you please tell me for this material what type of electrodes to be
used? And why this occoured ?? And what may be possible reason for
this occourance?

Regards,
Y.C.Shiva,
QA/QC Engineer,
+974 6166465
Doha Qatar.



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