I think we can not tell what is the exact reason for this crack .Because
many cases interfere in this matter. Such as :
1- Because the wrong process for backing of electrode it's possible to delay
cracking.
2- After root pass welder didn't do the second pass in the correct time &
the shrinkage causes the root crack.
3- Wrong grinding after root pass on the connection point could make the
small crack & because the shrinkage stress that crack propagated.
4- If the heat input became more than your WPS & cooling rate also high then
transformation of martensite phase is possible . This matter also could
cause the brittleness.
So my suggestion is you control these all items then sure you have not any
crack.
REGARDS
-----Original Message-----
From: materials-welding@googlegroups.com
[mailto:materials-welding@googlegroups.com] On Behalf Of Yadav Shiva
Sent: Wednesday, July 22, 2009 9:14 AM
To: materials-welding@googlegroups.com
Subject: [MW:2762] Re: 2742] Weld Crack at Root trough weld metal
We had done all the test HIC, SSCC. and the electrode is < 5ml/100gm
deposited weld. We can use 6010 or 7010 electrode for root and 8018
for fill and cap . But Is there any solution where it went wrong??
On 7/22/09, Sujeet Sangle <sujeetsangle@gmail.com> wrote:
> Dear Shiva,
>
> As said by Mr Ali , you must do all the NACE test HIC , SSCC .
>
> This 8010 Electrodes are with high level of Hydrogen more then 15 ml / 100
> gm .
>
> The weld has cracked due to delay cracking .
>
> Hope you have done the batch test of the consumable you are using for NACE
> tests ,
>
> AS suggested you can use 7010 Electrode's after batch testing .
>
> The other optin is also to go for 7016 down hand electrode .
>
> Regards,
>
> Sujeet Sangle
>
> 0091 9987781204
>
>
> On 7/22/09, Ali Varmazyar <av-ssg@msa.ir> wrote:
>>
>>
>> Surry, I forget to talk about your service. if your service is sour then
>> you
>> must consider Nace MR0175/ISO15156-2 requirements too.
>>
>> Best Regards
>>
>> A. Varmazyar
>>
>> MSA -Welding Engineering Department
>> Msa,Arak,Markazi,IRAN - P.O. 148
>> Tel.: +988612172725~6
>> Fax: +988612172702
>>
>>
>> -----Original Message-----
>> From: materials-welding@googlegroups.com
>> [mailto:materials-welding@googlegroups.com] On Behalf Of shiva
>> Sent: Tuesday, July 21, 2009 6:04 PM
>> To: Materials & Welding
>> Subject: [MW:2742] Weld Crack at Root trough weld metal
>>
>>
>> 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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