This is a demonstration of processing a reinforcing bar into a heat-shrinkable tubes using a carbon ring heater.
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Related page:
Heat shrink tube processing for electric wires 
No.2 Rust and corrosion prevention of reinforcing bars 
Shrinkage of heat shrink tube with heat resistance of 200℃ 
Heating of the heat shrink tubing with the Halogen Ring Heater 
No.9 Heat source of heat shrink tunnel 
No.14 Shrink processing 
Heat shrink film of battery 
No.10 Pre-heating glass processing