How to sweep a phyllotaxis in a desire section


I will be thankful if anyone tells me how to give a (for example circle) section to this shape.
the pipe is not a proper command because of errors in energy simulation.

in order to be helped it is better to give more informations and also to search a bit. There are tons of example.

By the way this could help

@laurent_delrieu Thank you for your answer.
after a lot of trying, now I have another problem. I need this offset curve to turn to the surface. just between two offset parts.

When i close the rectangle around it, it doesn’t create curve between them. the whole of rectangle turns to the surface.