surface repair
 

my design is not repaired by "surface repair", we can see in the file, I try multiple ways. any advice?
thanks

Do not worry about Close Proximity Faces & Poor Quality Faces.

Those 2 problems are solved by the surface remesher when you are meshing the part. They are only relevant on your Surface Mesh, not your Initial Surface.

I believed that it did my real problem that when I have to set, meshing general cylinder I get the error "no cylinder found" in manage cylinder

I see you have interfacse set up. The help page for the Generalized Cylinder Mesher says you cannot have interfaces when using it. They say you can delete the interfaces, mesh the problem, and then recreate the interfaces.

All under the help page article "Working with the Generalized Cylinder Mesher"

the pipe and the elbow and inside a fluid, I do not use boundary interfaces, but it is necessary to have two superfaces pipe and elbow, with this way I have cylonders. before I have the superface pipe+elbow then I should have two superfaces.