This is a demonstration of processing a round terminals into a heat-shrinkable tubes using a carbon ring heater.
Please check the following site for more information.
Related page:
No.11 Insulation of round terminals 
No.6 Waterproof protection for glass tubes 
Heat shrink tube processing of reinforcing bars 
Heat shrink tube processing of twigs 
No.12 Connector insulation 
Heat shrink tube processing of stainless steel pipe 
No.5 Waterproof protection for PVC pipes 
No.9 Waterproof protection for copper pipes