API 650 6th Edition Wind Load

[curlyjackme]

I am working on a tank that was originally built in 1982 to API650 6th Edition 3rd Revision. The wind girder is to be replaced 100%. I need to know the wind speed the tank was originally built to per API. Does anyone know what the wind speed in mph was in 1982 for tanks?

When I do the calculations per the current code it requires an intermediate wind girder also and the client does not want to add an additional wind girder to the tank.

Thanks in advance.

 

[fegenbush]

If you are not reconstructing the tank or changing the service, API 653 permits replacement of components in kind with the original (as-built) construction. If you have the original drawings, this is a straightforward process.

That being said, I am not sure what you are trying to accomplish by performing new calculations.

 

[curlyjackme]

The client ask for calculations to upgrade the tank to current wind loads.

 

[JStephen]

Looking through fairly quickly-
The "base design", which is now Appendix A, doesn't seem to have a wind-buckling criteria.
Appendix D, which is the current higher-stress option, did, but it is non-mandatory per a footnote. Default wind speed was 100 mph, which should be the fastest-mile speed, equating to the current 120 mph 3-second gust. It was allowed to vary for other wind speeds, and if not required by the owner, the calculated wind speed was reported to the owner.
It also allowed design based on transformed shell or average shell thickness methods.

 

[curlyjackme]

Thanks for all the reply's.