[solved] tube connection

[thschrader]

How did you create the model in FC? I see various tubes and rings. How did you create those surfaces and stitch them together?

Here is the file.
It is only one revolved sketch. I tried a more complex model before
(with additional planes), but part "boolean fuse" doesnt liked it.

steckverbindung_fem2D.FCStd

(11.33 KiB) Downloaded 32 times

For meshing I used netgen, max element size 30 mm, 1. order.
gmsh works too. Done with
OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15273 (Git)
Build type: Release
Branch: master
Hash: 4e77cee5ee6efa1b28290c10ccb8b2540b9eecaf
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: German/Germany (de_DE)

[thschrader]

At first sight, this joint look's more reliable
RogersCommission-v1p57.jpg
But, unfortunately it wasn't

Aaah...thats the connection of the shuttle-boosters, which failed at challenger-start.
Correct?

[thschrader]

Tube R660x22,2 mm steel S235 with revision-opening and stiffeners
at moment 200 kNm with sigma=49 MPa.
Design-moment is 900 kNm
sigma_new=900/200 x 49 = 220 MPa < 235 works...
calculix with 2D shells from gmsh

revision_opening.JPG (29.08 KiB) Viewed 512 times