How I can change bending radius on the imported part?
Did you convert the part to sheet metal or just use the insert bends command?
Using convert to sheet metal may bind you to the radii determined by the imported geometry though. May need to do a move face on the radii first.
I assume when you say "imported part" that you have a model with no separate features in the feature manager. If you have SW Pro or Premium you will have an addin called feature works that tries to reverse-engineer features. This works in pretty simple geometry parts. If not, you could try cut-extrude to cut the radius feature out and reapply a new one. Surfacing features could help with too.
If the purpose is just to unfold the part, you don't need to change the bend radius. Just plug in the desired bend deduction, bend radius wont affect the flat pattern. Otherwise, you can run the imported part through feature recognition and deal with it that way. After feature recognition, I would identify the radius features and delete them. Then when adding bends to the model, I would specify the desired bend radius....
Use Direct Editing with "Delete and Patch" activated. Click both sides off radius and delete it. Convert to Sheet metal and select new radius and thickness.
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