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Up Topic Welding Industry / Technical Discussions / CVN API 1104
- - By Toey TNDT (**) Date 01-16-2016 17:15
Dear All ,
I confused about Specimens on CVN Test.
What the number for test CVN.
in API 1104 stated Three specimen shall have the V-notch placed in  the weld centerline and
and the other three shall have the V-notch placed in the HAZ. but one word is total of 18 specimen
Weld Zone used 3 specimens
HAZ used 9 specimens
total 12 specimens
18-12 = 6
6 Specimens ?
Parent - - By Toey TNDT (**) Date 01-16-2016 17:20
If my language wrong i'm so sorry
Parent - - By js55 (*****) Date 01-18-2016 13:06
Hopefully you aren't working to the 21st Edition. In any case, I won't reconcile any math. I'll just say you will need 18 specimens. 9 weld metal. At the varying positions around the pipe, 6, 12, and 3/9 o'clock.
And be cognizant of other variables. Hopefully you don't have extreme ranges of thickness and diameter or it can get very expensive. I played with some numbers once on a project and hypothetically considered compliance to the 21st Edition. The impact testing was going to cost around a 1/4 million dollars. These people are insane.
Parent - - By Toey TNDT (**) Date 01-18-2016 15:42
Dear Sir ,
I'm reading API 1104 21 Edition 2013 only
Sometime if i have project about pipeline .
I will know for testing of CVN
Parent - - By js55 (*****) Date 01-18-2016 19:00
The problem with the 21st Edition is the Addendum for CVN's is insanely narrow pertaining to variables requiring requalification.
The 21st has not been accepted by DOT as yet so I would stay away from it if I could. Its bad enough with repair qualifications, its absolutely out of control on CVN's.
Parent - By Toey TNDT (**) Date 01-18-2016 23:45
Thank you for reply
I read ASME B 31.4 and B31.8 .
Welding for pipeline have to use API 1104 or ASME Section IX only.
Parent - - By mwmw (**) Date 01-18-2016 17:39
6 specimens shall be removed from 12, 6 and EITHER 3 or 9oclock =18
Parent - - By Toey TNDT (**) Date 01-18-2016 23:38 Edited 01-18-2016 23:54
Total 24 specimen ?
18 Specimens form Position 3 or 9
I have to prepare many pipe for testing CVN .

If i have 6" diameter i must have at least  3 pipe for testing

Regards,
Parent - - By mwmw (**) Date 01-19-2016 00:07
Its a total of 18 specimens
6 from 12oclock
6 from 6 occlock
and another 6 from either 3 or 9 oclock

Can you use B31.1 instead of Api 1104
Parent - - By Toey TNDT (**) Date 01-19-2016 01:36
B31.1 doesn't state impact test

Regards ,
Parent - - By mwmw (**) Date 01-19-2016 01:50
Does the contract state impact tests are required?
Parent - - By Toey TNDT (**) Date 01-19-2016 01:53
I just read api 1104 only don't have project spec.
Parent - By js55 (*****) Date 01-19-2016 12:58
Toey,
You are correct. There are no impact requirments in B31.1 since power piping is by definition a high temperature service. I have seen impact testing imposed on some alloys such as Grade 91 due to cold weather shipping and start up concerns predominantly. These would be handled by either customer specs or B31T.
On the other hand all you need for each set of variables is 18 specimens. 3 ea from the 3 positions for the weld metal and 3 ea from the 3 positions for the HAZ. The confusion usually lies in the fact that they give you a 3 o'clock/9 o'clcock choice.
However, once again be aware of variables and the possibility of having to do additional testing.
Up Topic Welding Industry / Technical Discussions / CVN API 1104

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