Internal Overlay of the first course of the bottom shell strakes

[Kiyan777]

I am currently reading API 653 to justify if welding a 8mm thick full internal overlay (360 degrees) around the first course of the current(5.8mm thick)shell bottom strakes is allowed.

The practice is currently being used were the bottom shell plates have exceeded it corrosion allowance and to correct the bottom course shell thickness.

These thanks were historically not constructed inline with API 650,hence the tanks have a common shell thickness from the bottom to the top ;ie 6mm thick.

Please advise on the code section reference or if this practice is allowed.


Thanks
Lee

 

[JStephen]

API-653 limits the size of lap-welded patch plates, and requires more extensive repairs to be butt-welded. See the "belly band" post a couple of lines down.