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