Hello,I need a hint on calculating the surface area of a pipe bend /to be more precise of the bends individual sections/, is this possible to do in autocad with 3d? is there such a library of functions? any suggestions or information appreciated. Big thanks Mike

Assuming consistent circular cross-section, the surface area is the pipe circumference times the centerline length.
 
If bent on curve of radius R, the centerline length is R x Bend angle (in radians).
 
A pipe of outer radius r, at a 45 degree bend would have length  R x 45 x (Pi/180), and a surface area of (2Pi x r)x (R x Pi/4)
 
That geometric method seems easier than a cad solution.
http://en.wikipedia.org/wiki/Torus
 
 
 

Hello, thank you very much for your input and explanation, a cad solution will be required here as the sections of the bend will have to be manufactured based on some graphic presentation. I assume it will be in 3d, but what I do not know is the module that I need to buy to be able to calculate /and depict/ the surface areas  and shapes for the individual sections in the pipe bend. So far I have found 2 candidates /AutoCad plant 3D and Autocad P&ID/ but I might be very wrong here, and maybe some other version might be totally suitable for these calculations and imagery. Thank you for the geometric method description as well, I am looking at it right now and it helps.Thank you & RegardsMichael

I think AutoDesk Inventor might be a better choice.