Impact test of Duplex SS material UHA-51(d)(3)

[Vishal Mistry]

I have a query regarding Impact Testing of Duplex SS Material.

As per ASME Section VIII Div. 1, Clause UHA-51(d)(3) Impact testing is exempted for Duplex SS as follows:

for the following steels in all product forms at MDMTs of −20°F (−29°C) and warmer:
(a) austenitic ferritic duplex steels with a nominal material thickness of 3⁄8 in. (10 mm) and thinner;

As per above statement I can understand that Plate/Pipe whose thickness is less than 10 mm or less that is exempted from the impact test. But what about the Duplex SS Weld neck or any other standard flange ? It will also exempt from the impact test or not ?

Please provide your suggestion on this issue.

Thanks & regards,
Vishal Mistry

 

[metengr]

ASME fittings and flanges will follow the same requirements in UHA-51 (d)3.

 

[SnTMan]

For something like a weld neck flange, the question becomes "What is the governing thickness?". It appears that the as-welded thickness is the "governing thickness" (UHA-51(a)), but to me that is uncertain, unless clarified as by an interpretation, etc. I use the quotes because the language does not appear in Part UHA.

The type of explanatory material found in Part UCS-66(a) & etc. is totally absent from Part UHA. I've always found that a bit odd.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[XL83NL]

Mike. Maybe this is a good time to dig in the Interpretation volumes to see if the query has been addressed before and if not, write the Code committee an Interpretation.

 

[SJones]

Looking outside of ASME VIII, it should be noted that Charpy testing can be used as a quality control tool irrespective of other code requirements: see, for example, API TR 938-C, or NACE Corrosion 2012, Paper 1096. Thus, simply because 'the code' doesn't require it, doesn't mean that Charpy testing should be completely neglected.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[SnTMan]

XL83NL, agree.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[SnTMan]

Found this Interpretation, taken together with UW-40(f) it seems definitive.
Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand