Thereby, the heater section is furnished with {TAIL ~ at least one distance control means} arranged for being in contact with the shell surface during the heating and for automatically regulating the second distance by means of {HEAD ~ a self regulating mechanism} 
Thereby , the heater section is furnished with { TAIL ~ at least one distance control means } arranged for being in contact with the shell surface during the heating and for automatically regulating the second distance by means of { HEAD ~ a self regulating mechanism }
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL 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 HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD