Tank Umbrella Roof Plates

[Scary999]

Can anyone give me the steps to calculate the flat plate dimensions of umbrella roof plate gores? I did calculate them with a Smoleys using logarithms years ago long before hand held calculators were available. I have looked over some of the steps using Autocadd but not sure they will yield the right dimensions. The ones I have looked at describe an elevation cut thru the roof and a plan drawn above. The problem I see with that is the plan diameter should be drawn using a radius equal to the arc length along the centerline of the gore. This does not allow the plan to align with the elevation end points. What am I missing?

Larry
ESP Tank

 

[HTURKAK]

Pls look previous threads .. One of them;

Umbrella Roof Geometry and Fabrication
thread1452-493044




He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48