Incomplete Penetration Acceptance Criteria B31.3 1

[WBH]

Is incomplete penetration rejectable by radiographic examination for normal fluid service to B31.3 Table 341.3.2 if the depth can not be measured (ex. inaccessible weld where depth can not be measured)? The length is acceptable. Depth can not be determined by radiographs

Acceptance criteria are given for length 1.5" long and 1/32" for depth

I have searched the ASME B31.3 interpretations back to 1987 with no results.

Any information would be helpful, thanks

WBH

 

[ijzer]

you could try to compaire the desity on the film at several locations and with that determine the depth of the incomplete penetration. Or use a step plate on the film.

 

[ndeguy]

Or have a length of flat ground on the weld cap part of which is directly above the region of IP so that the depth to the top of the indication can be measured with ultrasonics. If its a flat root bead (e.g. TIG) then a comparison from a radiographically-sound area can also be made.

Nigel Armstrong
Karachaganak Petroleum
Kazakhstan

 

[WBH]

Thanks for your responses,

I was more interested in the interpretation of the code in regards to acceptance/rejection criteria, when internal surfaces of the weld is not accessible by direct visual inspection.

My interpretation of the code is if the depth cannot be determined by direct visual measurement, then the incomplete penetration should be rejected as both criteria of the code have not been meet.

I am aware UT may be useful in this application, but no always practical.

 

[APIEric]

The interpretation of IF according to RT would be by length only, since RT is only practical in 2D.

 

[ndeguy]

One other parameter to consider is the root face dimension. if the root gap was too tight or the welder was not accurate in positioning of his root pass then quite likely the IP will be that height. Thus if the root face is greater than 1/32" then one should assume the worst case scenarion and repair even if less than 1,5" length.

Nigel Armstrong
Karachaganak Petroleum
Kazakhstan

 

[WBH]

APIEric

You are correct that it would be practical as it is 2D,

The code does not allow this practical assumption. It is clearly stated that both criteria must be meet regardless of the location of the weld. This is my quandary, as the code does not clearly address.

The undercut or ip is clearly present but the extent can not be measured. Either one could be defined as a defect by code if depth is exceeded, regardless of access.

Thanks for you input, this would clearly be debatable from both sides.

WBH

 

[WBH]

NDE Guy

I agree with your assessment and I would reject unless fabricator could prove the undercut or ip is less than 1/32". It is the fabricators responsibility to prove that the code requirements have been meet.

WHB