recess type tube to tubesheet weld

[212197]

ASME SEC VIII DIV 1 UW-20 specifies formula for tube to tubesheetweld design.
Pl. refer attached sketch for recess type joint. How to design the weld size? where can I get formula for it?
I want to know the basis of 0.6 mm fillet size.

 

[chicopee]

From past experiences with fired pressure vessel such as fire tube boilers, such weld is to seal from leak and is not is not considered a strength weld.

 

[SnTMan]

212197, you can size the weld by use of either UW-20 or Nonmandatory Appendix A, once you have decided whether it is to be a strength weld, partial strength weld or a seal weld.

From the given detail, I'd guess a seal weld.

Regards,

Mike

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

 

[212197]

As it seems to be seal weld, then expansion has to take the load & not the weld. In this case the expansion requirement is such that it shall not exceed 3 to 6% of wall thickness.
1.What would be the basis of 3 to 6 % permissible thinning?
2.How to design the tube to tubesheet expanded joint? Similar to UW 20 OF asme sec. VIII DIV 1 ,is there any code clause indicating the design formula?

 

[SnTMan]

212197, without knowing the tube material, I'd say that is a pretty light roll, 5 -10 % is more common I'd say. Perhaps the material is subject to rapid work hardening?

I would again refer you to Nonmandatory Appendix A. With that light a roll, testing the joint may be in order, if it is subject to appreciable loading.

Regards,

Mike





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