#include "shapes_lo.inc" //object{  Segment_of_CylinderRing(...)

union{ //-------------------------------------------------------
 #local Nr = 0;     // start
 #local EndNr = 8; // end
 #while (Nr< EndNr) 

object{ Segment_of_CylinderRing ( 1.50+0.05, 1.50-0.05 ,0.0015, -20)   

        texture{ pigment{ color rgb<1,1,1>*1}
               //normal { bumps 0.5 scale 0.005}
                 finish { phong 0.1}
               } // end of texture
         
        rotate<0,-Nr*40,0> 
      } // end of object 

 #local Nr = Nr + 1;    // next Nr
 #end // ---------------  end of loop 

rotate<0,0,0>
translate<0,0,0>
} // end of union ---------------------------------------------.