How to Test the Temperature Resistance of PTFE Insulated Wires

Based on the compatibility evaluation of PTFE insulated wires for hot runner applications described above, and the high temperature environment of hot runner systems, the following standard methods may be used to test the temperature resistance of PTFE insulated wires appropriate for hot runner scenarios:

Long-term constant temperature aging test: The wire sample is placed in a 260℃ high-temperature oven and baked at a constant temperature for 720 hours continuously. Test the changing rate of insulation resistance and tensile strength of the insulation layer before and after the test. The change rate <20% is a qualification which verifies the long-term temperature stability.

Instantaneous high-temperature impact test: 10 minutes immersion in a 320℃ high-temperature environment. Make sure insulation layer does not weaken, melt or split after removal so it can survive the instantaneous severe high temperature impact of hot runner systems.

High and Low Temperature Cycling Test: Complete 50 cycles of switching between high and low temperatures in the range of -65℃ to 260℃. The wire insulating layer does not exhibit hardening, brittleness or peeling after cycling, which proves its adaptability to the wide temperature range of hot runner working circumstances.

Actual working condition simulation test: The conductor was connected with the hot runner system and subjected to 100 complete cycles of stepped temperature rise and fall with the hot runner. No substantial drift in the dielectric constant of the conductor was seen during the cycle indicating the durability of its temperature resistance in real working settings.

The above tested PTFE conductor is entirely suitable for the long-term high-temperature operation requirements of the hot runner, eliminating difficulties such as anomalous rise of distributed capacitance and temperature control lag caused by insulation aging.