Sorry for the late response.
@ rich, I' followed the steps you proposed but I could not do a nice conversion from stroked lines to paths. After the conversion I've got closed paths (flat peculiar form) and after using several plugins to simplify the paths but there are still some closed paths. So rich, thanks for your solution and your effort, but I'm still searching for a solution.
@ Ottia Tuota, thanks for your answer, I still keep chopping paths and now I try to line up the chopped parts.
I wonder if I can name or number the different paths with the help of their length and then arrange a series of paths ? I used the 'Edit / Path summary' to find the lengths. In this case (spiral) the length differs on the chopped items.
@ rich, I' followed the steps you proposed but I could not do a nice conversion from stroked lines to paths. After the conversion I've got closed paths (flat peculiar form) and after using several plugins to simplify the paths but there are still some closed paths. So rich, thanks for your solution and your effort, but I'm still searching for a solution.
@ Ottia Tuota, thanks for your answer, I still keep chopping paths and now I try to line up the chopped parts.
I wonder if I can name or number the different paths with the help of their length and then arrange a series of paths ? I used the 'Edit / Path summary' to find the lengths. In this case (spiral) the length differs on the chopped items.