where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -
126291 views
Technical Discussions
Sanjay Nath
Sanjay Nath
09:06 Jul-11-2012
ASME B31.3 ACCEPTANCE CRITERIA

Dear All,


Please refer below for ASME B31.3 acceptance criteria. To reject any indication i need to comply 3 rules :-

1. It must be linear indication
2. The indication level must be above reference level
3. Comply with Rejectable length.

If i never comply with one of the above criteria i cant reject any indcation. How about Lack of sidewall fusion , lack of penetration and crack which is consider as a serious indication? Do i still need to follow this 3 rules or can i reject this indication since its a serious indication? I am just concern about small thickness and please advice. I just found one lack of sidewall fusion which is :-

Length :4mm
Amplitude level : 50% DAC
Material thickness : 5.49 ( 3" sch 40)



ASME B31.3-ACCEPTANCE CRITERIA

344.6.2 Acceptance Criteria. A linear-type discontinuity
is unacceptable if the amplitude of the indication
exceeds the reference level and its length exceeds
(a) 6 mm (1⁄4 in.) for Tw ≤ 19 mm (3⁄4 in.)
(b) Tw/3 for 19 mm < Tw ≤ 57 mm (21⁄4 in.)
(c) 19 mm for Tw > 57 mm


Sanjay Nath

 
 Reply 
 
Ed T.
Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III, Saudi Arabia, Joined Sep 2011, 169

Ed T.

Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III,
Saudi Arabia,
Joined Sep 2011
169
16:57 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

1. It must be linear indication
2. The indication level must be above reference level
3. Comply with Rejectable length.

First of all, where does it state in ASME B31.3 that an indication has to be linear to be rejected?

If you have Lack of Fusion or a crack or Lack of Penetration, it is rejected anyway, regardless of length. If you don't reject it, you're not doing your job.

 
 Reply 
 
Ed T.
Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III, Saudi Arabia, Joined Sep 2011, 169

Ed T.

Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III,
Saudi Arabia,
Joined Sep 2011
169
17:03 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed T. at 16:57 Jul-12-2012 .

The Acceptance criteria you quoted is for slag incusions. LOP, LOF ad cracks are all rejectable.

 
 Reply 
 
Bill
USA, Joined Jan 2010, 52

Bill

USA,
Joined Jan 2010
52
18:51 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed T. at 17:03 Jul-12-2012 .

Sanjay

You are correct. The other replys may be misking the code for B31.1 or posibly the RT acceptance in B31.1.

In any case 341.3.2 (acceptance criteria) states Ut acceptance will be 344.6.2. Normal fluid service states Ut will be 344.6 as does Server cyclic and Category M. So as long as it is metal pipe in a pressure class below 2500#, the UT acceptance criteria for B31.3 is as you stated, 344.6.2.

 
 Reply 
 
Ed T.
Ed T.
19:03 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Bill at 18:51 Jul-12-2012 .

Bill,

I am not mistaken. B31.3 does not permit Inomplete Fusion, cracks or Incompete Penetration. Nobody mentioned B31.1.

 
 Reply 
 
Bill
USA, Joined Jan 2010, 52

Bill

USA,
Joined Jan 2010
52
19:24 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed T. at 19:03 Jul-12-2012 .

Ed T.

Just words, please state your referance. I stated mine, 341.3.4 (Acceptance criteria), 341.4.3 (b)(1) (normal fluid service), 341.4.3(b) (severe cyclic), M344 (Category M),as did Sanjay in the original question, read it for your self.

My real hope is that Sanjay is working to an approved procedure that state exactly what his acceptance criteria is.

 
 Reply 
 
Ed T.
Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III, Saudi Arabia, Joined Sep 2011, 169

Ed T.

Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III,
Saudi Arabia,
Joined Sep 2011
169
20:20 Jul-12-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Bill at 19:24 Jul-12-2012 .

Well he didn't say if it was normal, sever cyclic or Cat M.
That makes a big difference.
I'm looking at the same refernce as you.

 
 Reply 
 
Jon Wallis
NDT Inspector, -
Netherlands, Joined Feb 2010, 626

Jon Wallis

NDT Inspector, -
Netherlands,
Joined Feb 2010
626
07:27 Jul-13-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

Does B31.3 allow UT examination with material 5,5mm thick? (RT I would have thought), also, Sanjay can you really determine a lack of fusion defect in 4mm length indication?

 
 Reply 
 
Sanjay Nath
Sanjay Nath
08:29 Jul-13-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Jon Wallis at 07:27 Jul-13-2012 .

Dear All,


In a first place my reference point is 341.3.3. My understanding of below statement is I need refer to 344.6.2 for ultrasonic examination for welds and elsewhere in the code. The 344.6.2 only mention about linear type indication is unacceptable and how about indication like porosity. When I refer to my Level 3, his answer is I need to refer table 341.3.2 normal and category M fluid service and the examination method should be RT. According to him we are doing UT in lieu of RT and that’s the reason we need to refer RT column. When refer to table 341.3.2-RT normal and category fluid service it is reject. This gave us confusion and we are just following whatever stated in the procedure.


Dear ED,

Please refer my first mail and I copy and paste ASME B31.3 acceptance criteria stated that a linear-type discontinuity is unacceptable if the amplitude of the indication exceeds the reference level and its length exceeds. If according to 344.6.2 the indication is acceptable and if refer to Table 341.3.2 its reject. Please correct me if I am wrong.


Dear Bill,

What you said is true. I am working to an approved procedure that state exactly what his acceptance criteria is.


Dear Jon,


As per my understanding, there is no thickness limitation given by ASME B31.3 for UT examination. If you refer to 344.6.2 it’s stated that 6mm length linear indication unacceptable for below 19mm thickness. Appreciated if you could provide me section at ASME B31.3 for thickness limitation for UT.

In a first place we perform phased array on the pipe and crosscheck with UT for our reference. After we post-processing our C-Scan view we found that the length is almost 4mm.


Sanjay Nath

 
 Reply 
 
Jon Wallis
NDT Inspector, -
Netherlands, Joined Feb 2010, 626

Jon Wallis

NDT Inspector, -
Netherlands,
Joined Feb 2010
626
09:30 Jul-13-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 08:29 Jul-13-2012 .

I admit that my version of B31.3 is from 2002 and maybe a later revision says different, but isn't UT method is according to ASME V? If this is the case, isn't the minimum thickness 8mm? Apologies Sanjay if I am out of date with ASME / B31.3.
What I meant with my other comment was not to doubt the measured length but to question the interpretation of LOF in an indication 4mm long. In other words, how do you know it's LOF and not a wormhole for instance?

 
 Reply 
 
Sanjay
Sanjay
11:15 Jul-13-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Jon Wallis at 09:30 Jul-13-2012 .

Dear Jon,

We are using Omniscan MX2 which come with overlay ( Bevel Configuration drawing) and able to pick up the inidication at full skip distance at one side only. Is it possible for you to let me know which part of ASME SEC V stated minimum thickness for UT is 8mm ? Maybe i can go thorugh ASME SEC V and it can be a good reference for me too. Appreciated your kind help.


Sanjay

 
 Reply 
 
Sanjay Nath
Sanjay Nath
07:53 Jul-18-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay at 11:15 Jul-13-2012 .

Dear All,

Kindly advice me and i still havent get any answers for my questions.


Sanjay Nath

 
 Reply 
 
Ed T.
Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III, Saudi Arabia, Joined Sep 2011, 169

Ed T.

Other, ASNT Level III, UT, RT, MT, PT, VT
NDT Level III,
Saudi Arabia,
Joined Sep 2011
169
12:36 Jul-18-2012
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 07:53 Jul-18-2012 .

I already told you.f it's Incomplete Fusion, Incomplete Penetration or a crack in accordance with B31.3, it is unacceptable regardless of length.

 
 Reply 
 
Michael Cunningjham
Michael Cunningjham
03:14 Jan-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 07:53 Jul-18-2012 .

Table 341.3.2 of B31.3 (2010) gives the acceptance criteria for VI, RT, MT & PT

With regard to where UT is applied in lieu of RT, Table 341.3.2 note (a) states "Weld imperfections are evaluated by one or more of the types of examination methods given, as specified in paras 341.4.1 etc." The "one or more" includes UT.

This seems to imply that for Linear indications that 344.6.2 is the acceptance criteria and that for all other indications that Table 341.3.2 applies.

 
 Reply 
 
azmath
azmath
10:50 Jan-26-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

what is acceptance criteria for overlap as per asme b31.3

 
 Reply 
 
michael cunningham
michael cunningham
21:59 Jan-28-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to azmath at 10:50 Jan-26-2013 .

It is section 341.3.2

 
 Reply 
 
cmaloney
NDT Inspector, - Plant Inspector
Applus RTD, Australia, Joined Nov 2000, 147

cmaloney

NDT Inspector, - Plant Inspector
Applus RTD,
Australia,
Joined Nov 2000
147
07:15 Jan-29-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to michael cunningham at 21:59 Jan-28-2013 .

At the risk of opening a very large can of worms, Sanjay is quoting the correct part of B31.3, (344.6.2) quoting from 341 is trying to enforce a RT acceptance on a UT acceptance! so Sanjay the real answer is exactly as the code says, any linear indication regardless of its type is rejectable if it exceeds the length parameter for thickness range if it exceeds the reference amplitude. Extract from B31.3 2010 below

344.6.2 Acceptance Criteria. A linear-type discontinuity
is unacceptable if the amplitude of the indication
exceeds the reference level and its length exceeds
(a) 6 mm (1⁄4 in.) for Tw ≤ 19 mm (3⁄4 in.)
(b) Tw/3 for 19 mm < Tw ≤ 57 mm (21⁄4 in.)
(c) 19 mm for Tw > 57 mm

Please note, I personaaly believe that this is a poor acceptace method as there is no consideration for discontinuity type. I mean how many cracks have you left in lately!

Collin

 
 Reply 
 
swapnil Bhatawadekar
swapnil Bhatawadekar
08:22 May-14-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

Dear sanjay,

Can you tell me the acc criteria for RT UT MPT & LPT In ASME standard .

pls send me on my email id


swapnil

 
 Reply 
 
Steven Doc
Other, Quality Manager
Siemens Energy, Egypt, Joined Feb 2011, 187

Steven Doc

Other, Quality Manager
Siemens Energy,
Egypt,
Joined Feb 2011
187
18:58 Sep-04-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

Interesting discussion, however no consensus of agreement.

I am currently having this discussion on applying PAUT on B31.3 NFS piping.

Impossible for me to believe that the intent of the Code is to allow 6mm Cracks and Lack of Fusion to remain in place, where RT rejects them.

 
 Reply 
 
bill
USA, Joined Jan 2010, 52

bill

USA,
Joined Jan 2010
52
17:38 Sep-05-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Steven Doc at 18:58 Sep-04-2013 .

It’s not interesting; it’s hysterical on one hand and tragic on the other. Even when references are provided nonsensical conjecture continues to litter the landscape.

As to what you do or don’t find possible to believe, and I mean this I the most academic of ways, it does not matter because that IS what’s written. Should you struggle with that statement you need only look to the rest of ASME for acceptance criteria’s that care not what a defects is, rather reject based on size. There are no less than 5 (ref: cc181, cc2235, cc189, Sec 8 div 2, Sec 8 div 3).

Now what is interesting is that B31.3 UT criteria fits neither the fracture mechanics nor workmanship definitions given in Art 4, rather sits somewhere in-between. However one could postulate that the amplitude requirement is the ‘height’ corollary and that would seem to make sense, if not fitting the definition of FM exactly.

Or maybe I’m just having a stroke, and I’m the one that’s tragic. You be the judge.

 
 Reply 
 
Peter Grimes
Peter Grimes
22:43 Sep-06-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 17:38 Sep-05-2013 .

"It’s not interesting; it’s hysterical on one hand and tragic on the other. Even when references are provided nonsensical conjecture continues to litter the landscape."

"Or maybe I’m just having a stroke, and I’m the one that’s tragic. You be the judge."

These phrases border on the offensive and have no place in a technical discussion.

 
 Reply 
 
Ed Ginzel
R & D, -
Materials Research Institute, Canada, Joined Nov 1998, 1292

Ed Ginzel

R & D, -
Materials Research Institute,
Canada,
Joined Nov 1998
1292
13:47 Sep-07-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 17:38 Sep-05-2013 .

Bill, I think you are on the right track. The comments expressing "concern" that cracks and LoF are allowed seem to be missing a few points. Most importantly is the OPTION to use an alternative acceptance criteria as described in CC181-2. This option is based on a Tier 2 acceptance criterion (i.e. assumes a worst case fracture toughness for all the approved materials in ASME). It also assumes that all flaws are cracks (i.e. have very small tip radii). It is a reasonable approach for thicker dimensions but tends to over estimate on thin wall (probably why the change from Code Case 181-1 to Code Case 181-2).
As for the flaw characterisation issue, this has always been a problem for NDT. In a recent study (PANI3) it was interesting to see that less than 50% of the characterisations were correct and these characterisations were all made by "qualified" PCN Level 2 UT operators.
The people whining about the code permitting specific flaws are perhaps unaware of the intent of the workmanship acceptance criteria. It is to identify process problems...it is NOT intended to assure fitness for purpose! When a fitness for purpose approach is used it really does not matter what type of flaw it is, it is treated as equivalent to a crack and even cracks can be "tolerated" if the service conditions to not exceed the stated safety margins.

2
 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
14:56 Sep-09-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed Ginzel at 13:47 Sep-07-2013 .

Ed

Forum members expressing their opinion on technical matters is not "whining" in my opinion. I hope this is an isolated aberration on your part.

Whats your view on acceptance for transverse flaws as required by ASME V Article 4 para T-472 Distance Amplitude Technique, T-472.1.3. Reflectors transverse to the weld. Does the >6mm, >100% DAC before rejection apply to these as well?

 
 Reply 
 
Ed Ginzel
R & D, -
Materials Research Institute, Canada, Joined Nov 1998, 1292

Ed Ginzel

R & D, -
Materials Research Institute,
Canada,
Joined Nov 1998
1292
03:12 Sep-10-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Nigel Armstrong at 14:56 Sep-09-2013 .

Nigel, this thread goes back a long way (July 2012) but the situation seems to have gone off the tracks in January of 2013 when, after correctly identifying the details of acceptance criteria in Parqa. 344.6.2, the comment was made that inferred cracks were allowed. This from the misinterpretation of a "linear-type" indication. The response seemed to suggest that a crack was no to be interpreted as a linear-type indication.
Much later in the year a comment was posted (Sept 2013) "Impossible for me to believe that the intent of the Code is to allow 6mm Cracks and Lack of Fusion to remain in place, where RT rejects them"...this also made no connection to the details of the Code paragraph quoted. Then a new post moves on to the use of "hysterical", "tragic" and "having a stroke" and the examples of fracture-mechanics-based acceptance criteria from ASME were quoted.
Using an old thread to raise unrelated issues and then inserting incorrect statements (opinions) with disparaging and simply incorrect remarks about code requirements is, in my humble opinion, whining.
As for "acceptance for transverse flaws as required by ASME V Article 4 para T-472 Distance Amplitude Technique, T-472.1.3" I think you need to be more specific. ASME V does not have acceptance criteria, it merely describes how the inspection is carried out.
Flaws that are detected having a transverse nature can be of several types. There are provisions in the "referencing Code Sections" as to how to deal with these. My concern for the reliability of operator characterisation still remains.

 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
17:11 Sep-11-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed Ginzel at 03:12 Sep-10-2013 .

"ASME V does not have acceptance criteria" - yes I realise that Ed, viz last sentence

And I am surprised by how far you veer far off your usual high standard of impartiality and sanguinity with your following comment:

"Using an old thread to raise unrelated issues and then inserting incorrect statements (opinions) with disparaging and simply incorrect remarks about code requirements is, in my humble opinion, whining."the thread heading is ASME B31.3 Acceptance Criteria.

The thread heading is ASME B31.3 Acceptance Criteria.

Never mind - we all have off days!




 
 Reply 
 
Luis Montoya
NDT Inspector,
Tecnicontrol, Colombia, Joined Dec 2010, 9

Luis Montoya

NDT Inspector,
Tecnicontrol,
Colombia,
Joined Dec 2010
9
00:39 Sep-13-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

hi Sanjay

in my opinion, i work whit this criterial aroun 4 years ago, and for me is clear, the diference between UT and RT criterial is based on POD of each technique, so if you catch a lack of fusion whit RT is because you don´t catch around 2 o3 more. but if you used UT you have aroud 80% to catch all lack of fusions.

so if you ask me if i accepted this indication, i allways say yes and im sure that if you want to make a correlation whit RT you didn´s see anything.

the criterial are different beacuas tha techniques have diferent way to catch the indicacions.

Luis Montoya

 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
16:30 Sep-13-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Luis Montoya at 00:39 Sep-13-2013 .

Luis

The method of imaging the defect may change how the defect is perceived, but it will not change the defect itself. If modern imaging equipment and software cannot provide us with sufficient information to match the capabilities of radiographic film
then it has made no real advances and the equipment manufacturers are misleading us. I don't believe this to be true.

Now we have digital UT Phased Array systems with advanced imaging software offering numerous views and we still say the method is incapable of categorising a defect 6mm or less length! I'm sure that PA equipment manufacturers make different claims. Modern PA imaging systems (and TOFD) in the hands of well-trained and experienced personnel are quite capable of detecting, positioning, sizing and categorising accurately defects 6mm and less.

To resort to selecting one phrase from the Code (which is perhaps based on the perceived capabilities of a good technician operating a manual UT system) whilst neglecting what is unambiguously stated previously is a calumny.

 
 Reply 
 
Luis Montoya
NDT Inspector,
Tecnicontrol, Colombia, Joined Dec 2010, 9

Luis Montoya

NDT Inspector,
Tecnicontrol,
Colombia,
Joined Dec 2010
9
23:21 Sep-13-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Nigel Armstrong at 16:30 Sep-13-2013 .

Hello Nigel

I believe there was a problem with my English, as it seems my comment was misunderstood and I actually agree with your position that "The method of imaging the defect may change how the defect is perceived, but it will not change the defect itself".
Let me attempt to explain myself better.

I have been working with PA+TOFD inspection for the last 4 years, using the criteria stated in ASME B31.3. Every UT inspector has to live with the very inconvenient and inaccurate comparison to RT.

For me and my coworkers it is clear that it is much more difficult to detect a 6mm-LoF with RT. Whenever we have had to validate a UT system against RT results, we have always seen that PA+TOFD detects many more indications than those shown in the radiography film. If the acceptance criteria used for PA UT were the same as the one used for RT, the rejection rate would be too high.

I hope I have clarified my point of view a little. I maintain that due to the manner in which the information is acquired the criteria should not be the same for UT and RT; at least until people without a lot of NDT knowledge understand that UT has greater visualization and sensibility capabilities than those of RT.

It is always very interesting to participate in these forums, there is always something to learn from the experience of others. I apologize again for my English in the previous post.

Luis Montoya and patricia Salas

 
 Reply 
 
ali yousefi
ali yousefi
14:56 Sep-15-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

zoom image

ASME B31.3 Acceptance

dear sanjay
ASME B31.3-2010 clearly describe general acceptance criteria Table K341.3.2
and for High pressure Piping in Table K341.3.2
LOF are categorized in Class A & extent of imperfection= zero
 
 Reply 
 
ali yousefi
ali yousefi
15:07 Sep-15-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

zoom image



for information
 
 Reply 
 
Robert Howland
Canada, Joined Sep 2013, 9

Robert Howland

Canada,
Joined Sep 2013
9
19:17 Sep-15-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to ali yousefi at 14:56 Sep-15-2013 .

Table 431.3.2 is not applicable if UT method is used, this is a common error / misconception.

My question is with the UT acceptance... as per 344.6.2, if a LINEAR indication is unacceptable if greater than reference or longer than 6mm - all fine and dandy... but what about volumetric defects? or (the unlikely event of) thru wall defects 5mm long?

 
 Reply 
 
ali yousefi
ali yousefi
13:00 Sep-16-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Robert Howland at 19:17 Sep-15-2013 .

zoom image



zoom image



Robert
Ultrasonic method was added in version 2010 Table K341.3.2
344.6 paragraphs describe UT and some of acceptance. But the acceptance criteria for each separate section referred to 341.3.2.
 
 Reply 
 
Robert Howland
Canada, Joined Sep 2013, 9

Robert Howland

Canada,
Joined Sep 2013
9
17:03 Sep-16-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to ali yousefi at 13:00 Sep-16-2013 .

I was not referencing sever cyclic, or elevated temperature conditions... under normal service, Para 344.6.2 applies, but makes no reference to volumetric defects only "linear".

Not big big deal, business as usual.

 
 Reply 
 
bill
USA, Joined Jan 2010, 52

bill

USA,
Joined Jan 2010
52
23:41 Sep-16-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to ali yousefi at 13:00 Sep-16-2013 .

Incorrect.

First your not reading from the latest edition.

Second you fail to read the complete paragraphs you quote which do in fact give further requirements. If you did you would see your mistake ( see 341.4.3 (b) and 341.4.4 (b) for the volumetric examination requirements of severe cyclic and elevated temp respectively. You will see they both send you to 344.6 for UT).

Lastly I'm lost as to why you would post reference to "K" which is high pressure piping, and incomplete I might add (this thread is about welds), then repost a reply to Robert Howland with incomplete and outdated quotes of elevated temp and sever cyclic. May I respectfully suggested you continue reading the paragraphs you quoted.

So let's try this one more time. Excluding non metallic and high purity chapters there are 6 basic categories of piping in B31.3. All of them except 2 requires 344.6 for the volumetric examination of welds. The 2 that don't are Cat D and high pressure. High pressure (above 2500lb class) requires section 8 div 3, and Cat D has no volumetric requirement at all. In other words if you are inspecting a weld to b31.3 for any service sans cat D and high pressure than 344.6.2 is the acceptance period. Table 341.3.2 only apply for NDT other than UT. If you look at the table you will see under "methods" UT in NOT listed.

When reading the UT acceptance criteria you will see that it states that the indication must be greater than reference amplitude and be greater in length than what's listed based on the thickness of the weld. Both of these criteria's must be satisfied. This criteria applies for all defects detected by UT irrespective of what is, including traverse defects. Lastly the term " linear type discontinuity" is how the paragraph starts. This statement seams to cause confusion to some. It does not mean planar (i.e. 2 dimensional as in LOF). It only means to happen in a line. Slag is volumetric but often can happen in a line, hence the common term Slag line. LOP is volumetric but can happen in a line. You get the point I'm sure. Just remember linear does not mean 2 dimensional vs 3 dimensional defects and the criteria applies to all defect types the same.


References:
Normal service- 341.4.1 (b)
Category D-341.4.2
Severe cyclic - 341.4.3 (b)
Elevated temp - 341.4.4 (b) (1)
Category M - M341.4 (b) (1)
High pressure - K341.4.2 and K344.6.3
Definition of planar and linear - NDT lexicon



 
 Reply 
 
Robert Howlnd
Canada, Joined Sep 2013, 9

Robert Howlnd

Canada,
Joined Sep 2013
9
01:51 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 23:41 Sep-16-2013 .

Indeed... i think we all agree the code needs some updates. After all, as its currently written, you could technically drill a 5mm Dia hole through the weld, and its still acceptable to UT.

 
 Reply 
 
ali yousefi
ali yousefi
15:34 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 23:41 Sep-16-2013 .

zoom image



zoom image



First: linear type indication is not planar defect. Refer to definition:

Indication, linear: in magnetic particle, liquid penetrant, or similar examination, a closed surface area marking or denoting a discontinuity requiring evaluation, whose longest dimension is at least three times the width of the indication.

Second: in 341.3 Examination Requirements have 3 factors for minimum Requirements
1: a & b (“a" clearly referred to 341.3.2 without exception)
2: 344.6.2 (344.6.2 is part of minimum requirement)
3: elsewhere in the Code (other Requirements)

341.3.2 Acceptance Criteria.
Acceptance criteria shall be as stated in the engineering design and shall "at least" meet the applicable requirements stated below, in para. 344.6.2 for ultrasonic examination of welds, and elsewhere in the Code.
(a) Table 341.3.2 states acceptance criteria (limits on imperfections) for welds. See Fig. 341.3.2 for typical weld imperfections.
(b) Acceptance criteria for castings are specified in para. 302.3.3.

According to attachment for normal fluid services acceptance refer to Para. 341.3.2 , Table 341.3.2 and 344.6.2
for examination performing refer to 344.6
 
 Reply 
 
ali yousefi
ali yousefi
15:38 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Robert Howlnd at 01:51 Sep-17-2013 .

i'm agree .
the code needs some updates.

 
 Reply 
 
Robert Howland
Canada, Joined Sep 2013, 9

Robert Howland

Canada,
Joined Sep 2013
9
16:52 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to ali yousefi at 15:38 Sep-17-2013 .

Ali, you are STILL incorrect. I thought we were talking about UT inspection under B31.3N??? you are correct in that acceptance criteria IS per para 341.3.2... but keep reading....

341.3.2 Acceptance Criteria. Acceptance criteria
shall be as stated in the engineering design and shall at
least meet the applicable requirements stated below, in
para. 344.6.2 for ultrasonic examination of welds, and
elsewhere in the Code


If you try to apply RT based acceptance criteria to UT, you will have unnecessarily high repair rates.

 
 Reply 
 
bill
USA, Joined Jan 2010, 52

bill

USA,
Joined Jan 2010
52
18:42 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to ali yousefi at 15:34 Sep-17-2013 .

Im lost. Is it simply a language barrier?

The code pictures you inserted prove what i stated.

341.4.1-"Acceptance criteria are as stated in para. 341.3.1 and table 341.3.2, for normal fluid service UNLESS OTHERWISE STATED."
Did you miss the last part of that sentence? The UT acceptance in 344.6.2 IS OTHERWISE STATED. How is that not clear? Even if you missed reading the complete sentence when you go to table 341.3.2 what part of that table would you use for UT? The RT section? The MT section? Because there is no UT on that table!!!!!!!! Again how could that not be clear to you?

You wrote; " First: linear type indication is not planar defect. Refer to definition:”. Did you read what I wrote? I don’t think you did. Let me help: " It does not mean planar (i.e. 2 dimensional as in LOF). It only means to happen in a line." and yes the definition of a line is 3 times width. So what? Other than incorrectly comprehending what I wrote, and in reply affirm my statement, did you have a point?

You wrote; “Second: in 341.3 Examination Requirements have 3 factors for minimum Requirements
1: a & b (“a" clearly referred to 341.3.2 without exception)
2: 344.6.2 (344.6.2 is part of minimum requirement)
3: elsewhere in the Code (other Requirements)”

1-Yes there is an exception, its UT. Why may you ask? Because the table it sends you to (Table 341.3.2) HAS NO UT ON IT!!!!!! All roads in B31.3 point to 344.6.2 for UT! No way around this my friend so stop quoting the MT, PT, RT, and VT table 341.3.2.
2-344.6.2 is not just a part of it; it is the ONLY UT acceptance in B31.3, except high pressure which sends you to section 8 div 3.
3-You mean all the other places that tell you use 344.6, hmmm we might be on to something.

You wrote; ”According to attachment for normal fluid services acceptance refer to Para. 341.3.2 , Table 341.3.2 and 344.6.2 for examination performing refer to 344.6” Again, did you miss the last part of the sentence “UNLESS OTHERWISE STATED”. The UT acceptance in 344.6.2 IS the "otherwise stated" it is talking about. As is the section in high pressure service.

Does it make sence now? I hope so.




 
 Reply 
 
bill
USA, Joined Jan 2010, 52

bill

USA,
Joined Jan 2010
52
19:18 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Robert Howlnd at 01:51 Sep-17-2013 .

Robert,

I asume your talking about worm hole porrosity however there is no issue for a couple of resons.

First unless its a single pass weld its not going to happen. Ive never seen nor heard of a thru wall por on multi pass welding.

Second if it were to occur it would fail the VT requierment.

Lastly most lines get sqeezed for leaks

Ive heard others quote that same line before about a thruwall hole but concider that 95% of normal service Circ welds are not subject to NDT. I think its all a worry without a problem.

B31.3 is one of the most clearly written, easy to comply with ASME codes there is. If your a UT guy you should love B31.3. The code has been arround since the 50's or something like that, and even earlyer in other forms. I would say the engineering in it is pritty well tested.

 
 Reply 
 
Robert howland
Canada, Joined Sep 2013, 9

Robert howland

Canada,
Joined Sep 2013
9
20:03 Sep-17-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 19:18 Sep-17-2013 .

Agreed, anyone doing UT to B31.3 will have an easy day. and yes, a thru wall hole is just hypothetical... banter.

1
 
 Reply 
 
ali yousefi
ali yousefi
08:46 Sep-18-2013
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Robert howland at 20:03 Sep-17-2013 .

with your thought Also anyone doing welding to B31.3 will have an easy day ...

 
 Reply 
 
siva.g
siva.g
09:24 Feb-03-2015
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to swapnil Bhatawadekar at 08:22 May-14-2013 .

I need RTFI Defect acceptance critirea level ASME B31.1, B31.3, B31.3, B31.4, ASME SEC VIII DiV.1, Div.2, API 1104, API650, ASME D1.1, D1.2, ASME SEC IX, PLEASE SEND ME MY MAIL ID CLEARLY SHORT NOTES.

 
 Reply 
 
Rahul Singh
India, Joined Dec 2013, 1

Rahul Singh

India,
Joined Dec 2013
1
13:26 Jun-09-2015
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

Dear Sir,

Lack of sidewall Fusion , lack of penetration and cracks are linear Indication .

They defects are come into the first rule .

Second things your indication amplitude level is 50 % compare to FSH or related to the DAC .

IF its the subsurface indication then you can give it as recordable .

not only you have to check the pressure of pipe but also check the pipe is come into the Critical zone or not .

and if you are going to give as recordable every month you have to monitor the Indication .
I think your indication is fabrication indication and this an initial stage indication .you Repair this one indication

 
 Reply 
 
D sharma
D sharma
05:40 Jun-12-2015
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Jon Wallis at 09:30 Jul-13-2012 .

Dear sir.i would like to know that ..what is minimum thk of ut test what is the matter behind it.
according to asmeb31.1 and asme b31.3 .rounded indication acceptance limit..

 
 Reply 
 
bharat gohil
bharat gohil
11:23 Feb-11-2016
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to D sharma at 05:40 Jun-12-2015 .

what is the minnimum thickness for lpt and ut test?

 
 Reply 
 
PHAN HOANG DIEP
NDT Inspector,
Vietnam, Joined Aug 2011, 15

PHAN HOANG DIEP

NDT Inspector,
Vietnam,
Joined Aug 2011
15
06:10 May-05-2016
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Ed T. at 12:36 Jul-18-2012 .

Ed T.!
As you said all lack of fusion, lack of penetration or crack all are rejected regardless length. Please point out for me where paragraph in Asme B31.3 code mentioned this one.
Note: For Manual UT only. (not UT replaced RT)
Thanks!

 
 Reply 
 
Shane Feder
, Quality Co-ordinator (SubSea)
Thailand, Joined Dec 2014, 89

Shane Feder

, Quality Co-ordinator (SubSea)
Thailand,
Joined Dec 2014
89
06:34 May-28-2016
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to PHAN HOANG DIEP at 06:10 May-05-2016 .

Download

Guys,
I realise this is an old post but thought I would give anyone interested an update.
I have submitted the attached Request for Code Change last year and it is slowly making its way through the system.
Cheers,
Shane
 
 Reply 
 
massimo carminati
Consultant, AUT specialist
IMG Ultrasuoni Srl, Italy, Joined Apr 2007, 691

massimo carminati

Consultant, AUT specialist
IMG Ultrasuoni Srl,
Italy,
Joined Apr 2007
691
11:35 May-28-2016
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Shane Feder at 06:34 May-28-2016 .

Very interesting! I agree with all your points. Good job!

 
 Reply 
 
sarath
NDT Inspector,
mispahpipeline.inspection, India, Joined Aug 2016, 1

sarath

NDT Inspector,
mispahpipeline.inspection,
India,
Joined Aug 2016
1
03:29 Aug-27-2016
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Robert Howlnd at 01:51 Sep-17-2013 .

which block used to plota dac as.per asme.b31.3?

 
 Reply 
 
Erhan Turgut
,
Turkey, Joined Jul 2016, 7

Erhan Turgut

,
Turkey,
Joined Jul 2016
7
09:41 Jan-09-2017
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to bill at 18:42 Sep-17-2013 .

Intention of the Code is very clear with the 2014 version (actually it was also clear before imo). It states :

341.3.2 Acceptance Criteria. Acceptance criteria
shall be as stated in the engineering design and shall at
least meet the applicable requirements stated below.
(a) Welds
(1) For radiography and visual, see Table 341.3.2.
(2) For magnetic particle, see para. 344.3.2.
(3) For liquid penetrant, see para. 344.4.2.
(4) For ultrasonic, see para. 344.6.2.

And even for Category M, severe cyclic or elevated temperatures UT is not a replacement of RT, is an option (only for cyclic condition it states "if specified in the engineering design" but again not a replacement)

I didn't understand why being anxious about UT acceptance criteria. E.G.API 1104 is accepting 25 mm LoP in particular cases ! This is all about design conditions imo.

And Code is giving a flexibility here. Don't forget the first rule : "Acceptance criteria
shall be as stated in the engineering design", not the Code. So, Code is giving the minimum criteria, Engineering shall decide to reject any crack or LoF regardless of length if they see any risk about that. If they designate 344.6.2 for UT they accept the responsibility.

I think it is more confusing if you are performing UT as per Chapter IX. Please check below message and comment ?
http://www.ndt.net/forum/thread.php?msgID=66450#66450

Thank you

 
 Reply 
 
Arif Sarwar
Arif Sarwar
17:48 Jan-09-2017
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

If a pipe joint (RT joint as per specification) is to be repaired to remove the crack and crack only exists in filling/ capping of joint, then is there any requirement of performing the RT of repaired joint?
From which code we can refer it?

 
 Reply 
 
selvam
selvam
13:51 May-08-2018
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay at 11:15 Jul-13-2012 .

dear sir
Im selvam from india, now i working ndt fields now i learn some technics dpt,mt,ut,utg,bororscope eddycurent tue inspections. so i need to acceptance creteria in dpt,mpi in aws d1.1,asme b31.3, asme b31.1. then ut acceptance creteria same like that dpt.


 
 Reply 
 
Osaid Akhtar
Osaid Akhtar
21:54 Oct-02-2019
Re: ASME B31.3 ACCEPTANCE CRITERIA
In Reply to Sanjay Nath at 09:06 Jul-11-2012 (Opening).

Asme code QW 191.2.3
When thickness is more than 6 mm then we can apply this code

 
 Reply 
 

Product Spotlight

GUL QSR1® Scanning

How do you measure pipe wall thickness without direct access to the area? QSR® Scanning - Guide Wav
...
e Quantitative Short Range Scanning.
>

Conformable wedge transducer

The conformability is obtained with a flexible membrane filled with water between the transducer and
...
the inspected component. The coupling between the membrane and the component requires a small quantity of water or couplant. The conformable wedge combines the acoustic performance of immersion technique with good coupling and low attenuation.
>

Robotic laser shearography enables 100% inspection of complex, flight-critical composite structures

An article in “Composites World Magazine” showcases Non Destructive Testing of aero-structures
...
with Laser Shearography. Over the years Dantec Dynamics has supplied many solutions for the aerospace industry. Referring to specific customer projects several of these cases are examined to outline the advantages of using Laser Shearography for automated defect detection.
>

YXLON Cougar EVO

Scalable small footprint X-ray inspection systems for assembly and laboratory applications. The
...
YXLON Cougar EVO series was designed to provide the "best-in- class" inspection solutions for SMT, semiconductor, and laboratory assembly applications, while maintaining a small system footprint for maximum convenience. With optimized software and hardware, these systems produce higher quality and more consistent results than other electronics inspection systems currently on the market.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window