The lance 3, wherein {TAIL ~ the opening width} in the circumferential direction is about four to eight times larger than the wall thickness of the webs in {HEAD ~ the circumferential direction} 
The lance 3 , wherein { TAIL ~ the opening width } in the circumferential direction is about four to eight times larger than the wall thickness of the webs in { HEAD ~ the circumferential direction }
OTH OTH OTH OTH OTH 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 HEAD HEAD HEAD HEAD HEAD HEAD HEAD