Verticality of vertical vessel

[280474]

Dear all,
My vertical vessel has vertical deviation of 119mm measured from skirt-vessel joint to top head of vessel. I have no verticality data during construction for this vessel as my references, and cannot find any information in ASME code regarding the allowable verticality value for such vessel.
Is there anyone has such information to evaluate the verticality of vessel ..?

 

[JStephen]

When analyzing the structure for stability due to wind or seismic loads, you can add in the lateral loading due to the tilt. It will quite likely be insignificant.

 

[ApC2Kp]

To 280474,

The out of plumb offset could be small factor for lateral loading. It depends how significant the 119mm compares to height and diameter. What may have more impact is the levelness of tower internals, if it has trays, etc.
I would suggest adding shims at skirt base ring to compensate.

The vertical deviation may have resulted from a large dimple or out-of-round portion of diameter. There are limits on out-of-roundness that may might depend on whether it is pressure or vacuum service.

 

[jte]

280474-

Just checking: You did measure the plumbness early in the morning, right? With a sunny day, the side exposed to the sun will be slightly hotter than the shaded side. With a vessel which is out of service (so no flowing fluid to help equalize things) this can make a difference. You might have heard of the "banana effect."

jt

 

[JStephen]

It could also be due to soil movement. In which case, you might plumb it up now, only to find it that far out in the other direction at some point in the future.

 

[280474]

All,
Thanks for the inputs.
I just try to find if there is such as rule of thumbs for vessel plumbness regarding their height and diameter.

 

[PAN]

280474,
Maximum deflection of tall vessel could be 1/200 x Height. What are the height and diameter ratio of this vessel?