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04:17 Feb-19-2004

Mehmet BAL

Consultant,
Turkey,
Joined Nov 2003
7
 1395 views
RT Interpretation of ASME VIII Div.1
Hi Everybody,
Can any one help to interpret the acceptance criteria of ASME Section VIII Div.1 (UW-51) given below:
For full examination, any group of aligned indications that have an aggregate length greater than Â“tÂ” in a length of 12 Â“tÂ”, except when the distance between the successive imperfections exceed 6L where Â“LÂ” is the length of the longest imperfection in the group.
Question:
1. From the above criteria what will be the distance between two close indications, or is there any maximum or minimum distance restriction?
2. How do you interpret when the distance between indications exceed 6L?
3. How do you interpret when the distance between indications less than 6L?
Thanks
Mehmet BAL

00:24 Feb-20-2004
Ed T.
Re: RT Interpretation of ASME VIII Div.1
----------- Start Original Message -----------
: Hi Everybody,
: Can any one help to interpret the acceptance criteria of ASME Section VIII Div.1 (UW-51) given below:
: For full examination, any group of aligned indications that have an aggregate length greater than Â“tÂ” in a length of 12 Â“tÂ”, except when the distance between the successive imperfections exceed 6L where Â“LÂ” is the length of the longest imperfection in the group.
: Question:
: 1. From the above criteria what will be the distance between two close indications, or is there any maximum or minimum distance restriction?
: 2. How do you interpret when the distance between indications exceed 6L?
: 3. How do you interpret when the distance between indications less than 6L?
: Your help will be appreciated.
: Thanks
: Mehmet BAL
------------ End Original Message ------------

You would consider a group of aligned indications as, just that, a group. If this group length is greater than Â“tÂ” or the wall thickness in any 12t it is rejectable.
For example, if the wall thickness is 2Â” and you have a group of aligned indications that are 2.5Â” long and is contained within 24", it is rejectable. (2Â” x 12=24Â”)
Now if these indications are separated by more than 6L it would not be considered as part of the same group and evaluated seperately. 6L indicates 6 times the length of the longest indication.
For example if you have a group of aligned indications 2mm each. One indication is 3mm. 6x3=18. If successive indications are separated by more than 18mm then they are not part of the same group. This would also be cause to evaluate seperately.
It can be confusing, but I hope this helps.

00:59 Feb-21-2004

N.Kuppusamy
Consultant, NDT Level-III Engineer,
Advanced Inspection & Testing (S) Pte Ltd,
Singapore,
Joined Dec 2003
34
Re: RT Interpretation of ASME VIII Div.1
Interpretation of UW-51
ASME Section VIII Div.1 UW-51Paragraphg(b)(3)is appliacble to agroup of aligned indications.

1. In any group of indications if the aggregate length is less than Â“tÂ” over the length of 12t, it is acceptable (irrespective of distance between successive indications) provided none of the indications in the group exceed the limitations given in UW-51 Paragraph (b)(2).

2. When the aggregate length exceeds Â“tÂ” over the lenght of 12t & the distance between successive indications more than 6L of the largest indication it is acceptable. They may be evaluated as two individual groups over next 12t length from each group.

3. It is rejectable if the distance between successive indications less than 6L of the largest indication and the aggregate length exceed Â“tÂ” over 12t weld length.

N.Kuppusamy
----------- Start Original Message -----------
: Hi Everybody,
: Can any one help to interpret the acceptance criteria of ASME Section VIII Div.1 (UW-51) given below:
: For full examination, any group of aligned indications that have an aggregate length greater than Â“tÂ” in a length of 12 Â“tÂ”, except when the distance between the successive imperfections exceed 6L where Â“LÂ” is the length of the longest imperfection in the group.
: Question:
: 1. From the above criteria what will be the distance between two close indications, or is there any maximum or minimum distance restriction?
: 2. How do you interpret when the distance between indications exceed 6L?
: 3. How do you interpret when the distance between indications less than 6L?
: Your help will be appreciated.
: Thanks
: Mehmet BAL
------------ End Original Message ------------

04:22 Feb-21-2004

Mehmet BAL

Consultant,
Turkey,
Joined Nov 2003
7
Re: RT Interpretation of ASME VIII Div.1
Thank you very much for your clear explanation.
Mehmet BAL
----------- Start Original Message -----------
: Interpretation of UW-51
: ASME Section VIII Div.1 UW-51Paragraphg(b)(3)is appliacble to agroup of aligned indications.
: 1. In any group of indications if the aggregate length is less than Â“tÂ” over the length of 12t, it is acceptable (irrespective of distance between successive indications) provided none of the indications in the group exceed the limitations given in UW-51 Paragraph (b)(2).
: 2. When the aggregate length exceeds Â“tÂ” over the lenght of 12t & the distance between successive indications more than 6L of the largest indication it is acceptable. They may be evaluated as two individual groups over next 12t length from each group.
: 3. It is rejectable if the distance between successive indications less than 6L of the largest indication and the aggregate length exceed Â“tÂ” over 12t weld length.
: N.Kuppusamy
: : Hi Everybody,
: : Can any one help to interpret the acceptance criteria of ASME Section VIII Div.1 (UW-51) given below:
: : For full examination, any group of aligned indications that have an aggregate length greater than Â“tÂ” in a length of 12 Â“tÂ”, except when the distance between the successive imperfections exceed 6L where Â“LÂ” is the length of the longest imperfection in the group.
: : Question:
: : 1. From the above criteria what will be the distance between two close indications, or is there any maximum or minimum distance restriction?
: : 2. How do you interpret when the distance between indications exceed 6L?
: : 3. How do you interpret when the distance between indications less than 6L?
: : Your help will be appreciated.
: : Thanks
: : Mehmet BAL
------------ End Original Message ------------

04:23 Jul-27-2005

# You may find it interesting to take a look at the sites in the field of...

20:27 Jul-09-2014
Re: RT Interpretation of ASME VIII Div.1
In Reply to Mehmet BAL on 04:17 Feb-19-2004 (Opening).

Suppost the Thickness of the Weld is 10 mm and We have to see in the Film of 12t means 120 mm... and It is Written the Aligned Indication Greater than T means Indication Legth is more than 10 mm, Suppose 13 mm (Supposte 4 Indication are there 4mm, 5mm, 6 mm,) but the Differnce Between the Indication Shall be Checked According to the Largest Indication ... 6T means the gap bwetween the Indication shall be of 6t atleast or greater otherwise its a repari

05:08 Feb-09-2015

LanhHuyet

NDT Inspector, ,
Vietnam,
Joined Jun 2013
22
Re: RT Interpretation of ASME VIII Div.1
In Reply to N.Kuppusamy on 00:59 Feb-21-2004 .

Please explain me : What is aggregate length ? Is the sum of the length of indications or the length from starting point of first indication and the end point of second indication.For example first indication has the length 3mm,the second has the length 2 mm? the distance between them are 2mm.What is the aggregate length in this case ? 3+2 =5 or 3+2+2 = 7 ?

10:23 Feb-10-2015

Lanh Huyet

NDT Inspector, ,
Vietnam,
Joined Jun 2013
22
Re: RT Interpretation of ASME VIII Div.1
In Reply to LanhHuyet on 05:08 Feb-09-2015 .

Hope to have the help from all of you for this problem.