ASME Sec.VIII Div-01-Appendix 1-6-dished cover-joint efficiency factor 2

[EngineerEPC]

Dear All,

For the dished covers shown in 1-6(b), 1-6(c) and 1-6(d), joint efficiency factors are not required as per code.
For dished cover as per 1-6(c), it seems possible since such type of construction will mostly involve a forging.

The covers for 1-6(d) will be formed as far as possible from a single piece of plate without any weld joint. if that is not feasible, then we need to do RT of the same.

Kindly elaborate the consideration by code for not considering joint efficiency factor.

Thanks and regards

 

[SnTMan]

Ariba01123, I'm kind of theorizing (guessing) here, but first, the details as shown contain no butt welds which are the only welded joints for which joint efficiency varies depending on examination. Kind of interesting that the language "no joint efficiency factor is required" does not apply to Fig 1-6 sketch (a). These heads must be designed with joint efficiency in mind.

I believe for the other sketches the Code assumes these formed heads are made from a single piece of plate.

However if one of these formed heads is made of sections butt-welded together I think this weld must be full RT'd to meet the condition that joint efficiency need not be applied.

My best guess anyway

Regards,

Mike

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

 

[Trestala]

I am assuming since the thickness is governed by bending (see equations applied), joint efficiency is not a factor in that direction.

 

[r6155]

Be care, the full penetration weld on the flange shall be examined.

Regards

 

[EngineerEPC]

Dear All,

Thank you for your replies.
= yes, it seems like they are designed with no welds or welds with full RT.

Thanks and regards