Thereby, the heater section is furnished with 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 {HEAD ~ means} of {TAIL ~ a self regulating mechanism} 
Thereby , the heater section is furnished with 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 { HEAD ~ means } of { TAIL ~ a self regulating mechanism }
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 OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL