Annular Plate & Bottom Plate sizes for Storage taks

[kvbalu2011]

Hi Members! Would like to know whether Annular Plate and the rest of Bottom plates can be of same thicknesses for a API650 Storage tank? Are there any thickness limitations that Bottom plates have to be thinner than the Annular plates.

 

[JStephen]

They can be the same thickness if the design permits.

 

[Syahar1975]

Yes, I have seen in many projects annular and bottom plate are in the same thickness.

Also I have seen they are not. It is depend on the calculation done by the tank designer.

 

[eHerrera]

Hi kvbalu2011.

According to API 650, paragraph 5.4.1 "All bottom plates shall have corroded thickness of not less than 6 mm (0.236 in)..." That is the only limitation.

About annular bottom plates, paragraph 5.5.3 refers to minimum thickness according to plate thickness and stress in first shell course.