Impact tests required on austenitic ferritic duplex steel 1

[Tony1t]

Are impact tests required on austenitic ferritic duplex steel,as attachment bracket plate of leg which essential to the structural integrity when weld to preesure part,when the MDMT is +32°F or colder, and the thickness limit of UHA-51(d)(3)(a) in Section VIII, Division 1 is exceeded? thks !

 

[stanweld]

Review Section II, Part D.

 

[SnTMan]

TonyTao, if your attachment is essential and the 3/8" thickness limit is exceeded you will have to use impact tested materials and weld procedures. For this weld, production impacts are not required.

Regards,

Mike

 

[Tony1t]

Thanks sanTMan.Whether there are exit an code interpretation as your viewpoint?

 

[SnTMan]

Don't know of one, but doesn't seem necessary to me.

Regards,

Mike

 

[TomBarsh]

TonyTao, you ask if there is a Code Interpretation to support the view that impact testing is required, this is not necessary because the Code states the requirement explicitly. See UHA-51(a), "impact tests shall be performed on all materials listed in Table UHA-23 for all combinations of materials and MDMT except as exempted by UHA-51(d), (e), (f), (g), (h), or (i)."

UHA-51(d)(3)(a) provides some exemptions from impact test for austenitic ferritic duplex. However, from your description of the material it is not exempt, as based on thickness and need structural integrity. Because it is not exempt, impact testing will be required per the main paragraph.

You may be able to exempt with UHA-51(g) as based on low calculated stress ratio.