Shrink fit Teflon insulation onto a wire by heating a stainless steel pipe as a susceptor using induction. The target shrink-fitting temperature is 660°F (350°C) and overheating of the inner wire must be prevented to achieve a uniform shrink-fitting of the insulation.
Stainless steel pipe
Fixture for the stainless steel pipe
Wire, 0.035 in (0.014 cm) diameter
Temperature: 660°F (350°C)
Power: 0.4 kW
Time: 35 secs.
- The stainless steel pipe will be used as a susceptor to heat the Teflon insulation around the wire.
- A simple fixture to hold the stainless steel pipe was made to prevent the wire and insulation from touching the hot surface of the pipe.
- The thermocouple was attached to one end of the tube and to the induction generator to use the generator’s thermo-regulation.
- Initial heating with thermo-regulator parameters:
Power set: 20%
Temperature set: 660°F (350°C)
Temperature zone: 390°F (200°C)
Temperature offset: 75°F (24°C)
- Feed and move the wire through the heated susceptor (the stainless steel pipe).
- Main objective of the test was achieved.
- The Teflon insulation is shrink-fitted with high quality, and the wire is not damaged by the process.
- 2 kW air cooled unit is suitable for the process.
- The Teflon insulation can be heated from the “outside” using controlled process.