Verticality of Support Leg Spherical Tank

Date 09-18-2013 07:27

Dear All

We have constructed Spherical Tank (ASME VIII Div 2), But we don't know about code construction for support Leg (limitation of plumbness).

Could you help me about that? Thanks before

regards

Max

By 803056

Date 09-18-2013 16:33

AWWA, AISC, and AWS D1.1 come to mind.

Al

By Joey

Date 09-23-2013 09:14

Structural (non pressure boundary) welding requirements either AWS D1.1 or AWS D1.6.
When approved by the purchaser (engineer) welding procedures may be qualified per ASME Section IX.
Straightness tolerance should be stated in erection procedure, you may ask the engineer if not stated.
e.g. For tank, the plumbness tolerance is 1/200 of the total tank height, same as for column or other vertical internal component.

~Joey~

By G.S.Crisi (****)

Date 09-23-2013 19:16

Max,
Such tolerances are not stated on Codes. They're mentioned on Engineering Standards issued by engineering firms or users.
For spherical tanks supporting legs, Petrobras, the Brazilian state oil company, establishes an out of plumbness tolerance of 1 millimeter per meter, up to a maximum of 6 millimeters.
Giovanni S. Crisi
Sao Paulo - Brazil