If you want to define a complex bend like this you need to define it through three separate bends: Two part that only bend horizontally and the center part that bends in a different bend plane.
Defining the polygon points for these bend parts is not trivial. Furthermore, we are not sure whether this complex bend is actually possible (without kinks between parts of the bend).
Our approach would be to approximate this situation by using a single bend with the combined bend radius of Rc.
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RE: Combined bends #2
Hello Bas,
You can use the combined bend radius at the tangent point where the overlap exists, see formulae NEN 3650-1:2012 E.1.2.4.2:
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Create also new tangent points as Jens also explains for the horizontal and vertical bends before and after the combined bend. You can do an exact calculation in Excel where the extra tangent points (X,Y,Z) should be. So you have multiple bend radius connecting with each other without any kinks.
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RE: Combined bends #2
It would be nice if overlap of two elastic bends are allowed in the POLYDIF input table. It can be mathematically calculated. Some output tables where the elastic bend radius is given/used should change then with a (partly initial elastic bend radius) + (partly) combined elastic bend radius + (partly initial elastic bend radius) . No cold or hot or mitre bends identifiers should be then allowed between the two elastic bend identifiiers.
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RE: Combined bends #2
(19-06-2018, 12:18 PM)Dr. J Foerster Wrote: Allowing overlapping elastic bends might indeed be a useful addition to the program. I assigned ticket no. J-2203 to this improvement request.
I have managed to that in Excel which splits the 2 elastic bends with new elastic bend(s) and a combined bend.
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RE: Combined bends #2
(21-04-2019, 04:35 PM)shaswin Wrote:
(19-06-2018, 12:18 PM)Dr. J Foerster Wrote: Allowing overlapping elastic bends might indeed be a useful addition to the program. I assigned ticket no. J-2203 to this improvement request.
I have managed to that in Excel which splits the 2 elastic bends with new elastic bend(s) and a combined bend.
Here are some background documents I used, which mostly are available online.