I am currently working on a proje

[bogu]

I am currently working on a project where I have to support on vessel on top of another via saddles supports i.e. the bottom of the top vessel saddle is curved to fit onto the top of the bottom vessel. As referenced in AS1210 I can use BS5500 or zick for the, shall we say normal saddles but I am not sure how to go about the saddle attached to the top of the bottom vessel. I do not have access to FEA and normaly write a calculation sheet in MathCAD.

Thanks in advance

 

[dbuzz]

Bogu,

I assume that the two vessels are horizontal, cylindrical vessels and that the two sets of saddles are aligned in conincident vertical planes.

You have a difficult problem on your hands!

The gravity loads from the upper vessel will try to "crush" the lower vessel. It's unlikely that designer of the lower vessel ever anticipated the loading configuration now proposed. I anticipate that you will find that the lower vessel to be structurally inadequate for the proposed loading.

I'm not aware off-hand of any classical solution on which you could base your calcualtions (I'm away from the office and my trusty copy of Roarks!).

If you don't have FEM/FEA capability in-house, I recommend that you out-source it to a suitably experienced Engineer with that capability.

Alternatively, is there sufficent space for an indpendent structure to support the upper vessel and take the loads to ground (or the deck as the case may be).

 

[aybee]

Bogu . this is a common method of "piggy backing" heat exchangers . As far as I know they refer to Zick for shell/support stresses.Aybee

 

[aybee]

apologies all I forgot to say who "they" were ,,refer to TEMA the heat exchanger reference for piggy back exchangers..Aybee