In case that the forming drum is a polygonal cylindrical forming drum {HEAD ~ whose one side} of {TAIL ~ the polygon} has a length obtained by multiplying π inches by an integral number, the belt shaped members are more easily attached to the forming drum 
In case that the forming drum is a polygonal cylindrical forming drum { HEAD ~ whose one side } of { TAIL ~ the polygon } has a length obtained by multiplying π inches by an integral number , the belt shaped members are more easily attached to the forming drum
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH