Appendix28

[teran]

Hi. All,
Do I have to prepare sample coupon to verify value of "K" whether in range of 0.6 through 1.0 base on following condition?

Condition) Plate mill maker tested through thickness test and the result is 0.7(K value)

Thank
teran

 

[ijzer]

The answer is YES.

 

[SnTMan]

My reading is that you may take K = 0.6 without through-thickness testing, and that through-thickness testing may be performed by either the material supplier, or by the vessel manufacturer.

If plater maunfacturer has tested already per SA-20 and SA-770 and the MTR reflects this, it looks to me like you could use K = 0.7 without further testing.

Caution: I am not intimate with Apx 28.

Regards,

Mike

 

[ijzer]

Without further testing means without futher testing the tensile strength in Z direction. A weld test similating the corner weld is however still required per App. 28

 

[SnTMan]

ijzer, agreed. The joint qualification is still required.

Mike