Hot Work above Floating Roofs

[kaye13]

We have a leak in the shell of an external floating roof tank. I wanted to know if it is an accepted practice to allow welding on the shell above the floating roof. We propose to place fire blankets over the seal area and float the roof with water, but expect residual oil in the tank.

 

[Bonswa]

What is the height of the tank?
What is the height of the leak?
What is the product being stored?
What is the thickness of the shell that would be welded on?

In my opinion, if you absolutely cant limit the height of the tank to the height of the leak, then you could repair it. you could try a different method though. There are many different types of epoxy that would probably help. if it's just a pinhole leak that would require a small lap patch. you could buff down to bare metal on the shell and lap patch. apply the epoxy to the back of the patch and stick it to the shell. we've used epoxy to seal leaks on floating roofs until we could take the tank out of service. depending on the height of the leak, it could be a possibility.

 

[IFRs]

If there is one hole, my thoughts would be: why is there a hole and where are the other holes going to be next?

 

[211272]

hi ,hazard is relatif to vapor pressure of the product stored,i recommand to use cold repair with BELZONA. i have already do it on LNG ROOF TANKS and GAZOLINE TANKS.
best regard.