Re: Design of atmospheric rectangular tanks

On Feb 4, 2008, at 5:17 AM, iliasvitalis77 wrote:

> Where can I find some code information (if any) on the design of
> atmospheric rectangular tanks (i.e wall thickness calculation)?
Your very best guide is Appendix 13 of Section VIII of the ASME Code. This kind of vessel is designed as if it were a rectangular frame subject to uniform loading. Appendix 13 provides a methodology for figuring stresses at mid-span and at the corners for various configurations including stiffened tanks.

The bad news is that Appendix 13 is very poorly written and difficult to follow because no attempt whatever was made to make the arithmetic easier by simplifying the formulas algebraically. The good news about the bad news is that once you've fought your way through the first case, you can do the simplification yourself and work out a spreadsheet that will make life a lot easier for you.

The really bad news is that rectangular tanks are a wretchedly inefficient way to contain fluids. Wall thicknesses are enormous compared with circular tanks and the fabrication is expensive because of the need for hand fitted and welded stiffeners.

Christopher Wright P.E. |"They couldn't hit an elephant at chrisw@skypoint.com | this distance" (last words of Gen.

.......................................| John Sedgwick, Spotsylvania