main hoop bending

[Karam El Hady]

Hi......I'd like to ask about main hoop bending when we bent the main hoop like cad model we got two main hoop but we face problem in image (1) when we bent it we got bending right in the middle of main hoop like pic which doesn't exist in cad model ; when we try to bend it again like image (2) we got reduction in the diameter like pic the reduction about 2 mm * in the black circle* So Is one of them acceptable ??
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[Jonny Rochester]

T3.10.7 The minimum radius of any bend, measured at the tube centerline, must be at least three times the
tube outside diameter. Bends must be smooth and continuous with no evidence of crimping or wall
failure.

I assume you have met this rule for the bend radius. Looking at your photos, the "crimping" is not that bad. It would be borderline pass. "No evidence" is hard to gauge, as it depends how hard you look.
I couldn't find the rule that defines crimping.

Here is the trick: Weld your roll hoop supports higher up. Create a "node" closer to the main arc of your bend, weld your supports here. The welded joint will hide minor crimping of the roll hoop.