[PSUBS-MAILIST] Pressure Hull Calculations

[Eric Bruhahn via Personal_Submersibles]

 Hi All,

I've been having issues getting the ABSHullCalc spreadsheet to work for me,
most of the function macros show as #MACRO? using Open Office Calc or
#NAME? using MS Excel even with macros enabled.

So I've been trying to use Procedure 2-2 in the Pressure Vessel Design
Manual and having some questions.

For a 120" cylinder including heads, 40" diameter with 0.25" thick 516gr70
plate and a Px of 175 psi I'm getting Pa=29.2psi. So, to calculate required
stiffeners to raise Pa I'm trying to use 1.25"x0.25" T rings with 10"
spacing (Ls) and getting I=0.618, As=0.625 giving me Factor "B" of 1,411 if
P in the calculation is 14.7 psi. Now the problem with this is my Factor
"B" is not even shown on Figure 2-1g. Increasing my Ls to 20" gives Factor
"B" of 1,568, closer but still short of the lowest number in the figure of
2,500. In step 10 am I reading it right as I=(0.16*(Do^3)*Px*Ls)/E ?

Can anyone see what I'm doing wrong here?

-Eric
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