In yet another preferred embodiment, {HEAD ~ the source} of heated air and {TAIL ~ the hollow structural member} are connected by a flexible connection which permits axial and rotational between the source of heated air and the hollow structural member 
In yet another preferred embodiment , { HEAD ~ the source } of heated air and { TAIL ~ the hollow structural member } are connected by a flexible connection which permits axial and rotational between the source of heated air and the hollow structural member
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH TAIL TAIL 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