out of Plumbness Tank 1

[Shahin71]

Dear All:

We have a newly constructed tank which after inspection by third party found out of plumpness in two locations.

1. What is the best way to get the situation corrected.
2. In case owner accepts the tank with current situation, is there any design variable need to be verified or run the calculation for.

Best regards

 

[chicopee]

what happened? Has the shell to bottom joint rotated, foundation locally settled, paper thin shell?
You need to provide more info. for responses to your inquiries.

 

[JoeTank]

Dude, help us out with some info!!!!
What are the tank dimensions?
Was the tank built to API-650?
Were the measurements taken before or after the hydrotest?Was the foundation originally built within the required tolerances?
How far is it out of tolerance?


Joe Tank

 

[chicopee]

Seems like Shahim71 does not know much!!!

 

[Shahin71]

Chicopee and JoeTank

I'm sorry I was little away


The tank is 36.0 m Dia and 14 m H designd as per API 650 10th Edition ADD4

As plumbness is a regular thing to inspect during tank construction as per API 650 and has to be within 1/100 range. This tank was found out of plumbness when it was at the last ring erecton. 40 mm more than the allowable towards the tank center.

Foundation is ring wall beam. No problem with tank bottom to shell or foundation.

Tank is still not hydrotested.

Thanks for your cooperation

 

[chicopee]

Is the tank roof welded?

 

[chicopee]

also where are in relation to each other the two out of plumbness sections? any manholes by those sections? any unusual features? how many courses in that tank? any detail may help.

 

[Shahin71]

Thanks Chicopee

Yes tank roof is welded. The two locations are opposite to each others

The tank is 7 courses each is 2.0 m

Client is ready to accept the deviation provided the design calculations are not affected. Is there any calculation need to be verified due to this non conformity

Thanks again for the help

 

[JoeTank]

If the tank is completed and the out-of-plumb exceeds the API limit, then the situation may be accepted based upon agreement of the parties. The out-of-plumbness does not affect the design calculations. The only adverse effect would be performance of a floating roof, if installed at a later time.

Joe Tank

 

[chicopee]

so is the out of plumbness parallel to each other or would they intersect each other if you extended imaginary lines? also is the top course only out of plumbness or is it the entire length of the wall?

 

[Shahin71]

Joe

Thaks alot

This realy answers my question

A star for you

Chicopee

Thanks alot

Best Regards