Maximum Allowable patch size of the Shell API653
Maximum Allowable patch size of the Shell API653
(OP)
Hi every one
Recently we inspected a internal floating roof tank and found that at 6 Feet from Bottom of the shell height all around the circumference a band of 36 inch width on shell was found pitted and corroded, Upon sand blasting several holes were found in this locations.
This tank was out of service for several years.The question is to bring back this tank into operation. Our maintenance team proposes to weld patch plates around the circumference ( internaly) of the tank in this corroded band. They touch base with the floating roof designer and he informed that there is no problem for the movement of the floating roof. But the API653( 2009 4th edition, section 9.3.1.7) limits the maximum size of the patch 48"X72". Is it acceptable to have multiple patch around the tank to cover the full circumference ???? or anyother type of solution is required to adhere to the code regulations. your quick response will be appreciated
Recently we inspected a internal floating roof tank and found that at 6 Feet from Bottom of the shell height all around the circumference a band of 36 inch width on shell was found pitted and corroded, Upon sand blasting several holes were found in this locations.
This tank was out of service for several years.The question is to bring back this tank into operation. Our maintenance team proposes to weld patch plates around the circumference ( internaly) of the tank in this corroded band. They touch base with the floating roof designer and he informed that there is no problem for the movement of the floating roof. But the API653( 2009 4th edition, section 9.3.1.7) limits the maximum size of the patch 48"X72". Is it acceptable to have multiple patch around the tank to cover the full circumference ???? or anyother type of solution is required to adhere to the code regulations. your quick response will be appreciated





RE: Maximum Allowable patch size of the Shell API653
RE: Maximum Allowable patch size of the Shell API653
RE: Maximum Allowable patch size of the Shell API653
Maybe this is should be submitted as an enquiry case to the API?
Adam Potter MEng CEng MIMechE
www.ax-ea.co.uk