Add an additional weld layer 2

[jakov11000]

Hi,

A nozzle has been welded to a flat cover (fillet weld).
After measuring throat thickness of this fillet weld (two days after welding) it was discovered that there is 1mm less than required thickness.

Can additional layer of weld be simply added to fulfill required (per UW16) throat thickness without removing the nozzle?
Would additional WPS or some procedure be required in that case?

Thanks

 

[metengr]

Yes, a weld pass to increase the fillet weld leg length and throat can be added using the same WPS.

 

[r6155]

1mm ???!!
1mm is nothing, let the weld as built.

Regards
r6155

 

[DekDee]

r6155,
If a minimum or maximum measurement is given by the code / standard it must be complied with no matter how pedantic it may seem to you.
If left up to you where do you draw the line ? 1.2 mm, 1.5 mm, 1.8 mm, 2.0 mm ??????
I agree that 1 mm is a miniscule measurement but if jakov11000 has measured an undersized weld (or the inspector has) then it is non compliant and requires rectification - exactly what he was requesting in his original post,
Regards,
DD

 

[r6155]

Please see
1)

http://www.eng-tips.com/viewthread.cfm?qid=231375

2) Asme III 2015
RULES FOR CONSTRUCTION OF NUCLEAR FACILITY COMPONENTS
Division 1 - Subsection ND
Class 3 Components

ND-4427 Shape and Size of Fillet Welds
(a) Fillet welds may vary from convex to concave. Except as permitted in (b) below, the shape and size
of the weld shall be in accordance with the requirements of Figure ND-4427-1. A fillet weld in any single continuous
weld may be less than the specified fillet weld dimension by not more than 1/16 in. (1.5 mm), provided that the
total undersize portion of the weld does not exceed 10%
of the length of the weld. Individual undersize weld portions shall not exceed 2 in. (50 mm) in length. In making socket welds, a gap as shown in Figure ND-4427-1 shall be provided prior to welding. The gap need not be present
nor be verified after welding. For sleeve type joints without internal shoulder, the gap shall be between the butting
ends of the pipe or tube.
(b) Socket welds smaller than those specified in Figure
ND-4427-1 may be used provided the requirements of
Article ND-3000 are met.

3)Hand calculations can be made to verify stresses in fillet weld before any desition.

Regards
r6155

 

[metengr]

Cherry picking from ASME B&PV Code books to resolve issues that are not applicable to what is being constructed or fabricated to another construction code is irrelevant. If the fillet weld requires a minimum throat size, and the client is paying for this design requirement, you deliver it.

 

[r6155]

1)Minimum thickness has tolerance too.

2)ASME VIII Div 1 U-5 TOLERANCES
The Code does not fully address tolerances. When dimensions,sizes, or other parameters are not specified with tolerances, the values of these parameters are considered nominal, and allowable tolerances or local variances may be considered acceptable when based on engineering judgment and standard practices as determined by the designer

3) PD 5500:2015
A fillet weld with an apparent throat thickness smaller than that specified should not be regarded as imperfect if the actual throat thickness with a compensating greater depth of penetration complies with the specified value (1 mm max.)

4)ISO 5817: similar concept

I hope that "ASME III ND-4427 Shape and Size of Fillet Welds" shall be included in future editions of ASME VIII.

When tolerance is not clear in the contract is a commertial topic.

Regards
r6155

 

[jakov11000]

Thank you all!

 

[DekDee]

r6155,
Weld acceptance criteria's - which the post is related to have absolutely nothing to do with tolerances.
UW 16 is quoted in the OP so it appears ASME VIII Part 1 is the applicable construction code - why on earth would you post excerpts from ISO 5817 and PD 5500 ?
jakov11000 asked for advice and he received it - you then decided to add your idea of an acceptance criteria ???
Regards,
DD

 

[r6155]

There are many resources to resolve it without weld.
Add 1 mm of weld is not necessary.

Regards
r6155