Insulation resistance, conductor resistance ρ≤4.95Ω/km, 20°C; sheath surface resistance ρ≥109Ω.cm.
The pressure test water temperature is 20±5℃, the immersion length is 10M, the time is 1H, the AC power frequency voltage is 8000V, and it is stored for 5 minutes without failure.
After being immersed in oil, the secondary oil resistance (ISO1817) test was performed, and the compressive strength retention rate was 60% or higher. The retention of tensile elongation after oil immersion is above 70%; the diameter change after oil immersion is less than or equal to 160
Combustion test: Vertical combustion test: the distance between the upper fixed point and the starting point of carbonization is greater than 50 mm. The distance from the lower flame to the upper fixed point is less than 540 mm. Combustion gas corrosion test: PH value ≥4.3, conductivity ≤10μS/mm.
The mechanical properties of the sheath. Tensile before aging: tensile strength ≥10.0N/mm2; elongation at break ≥300%; after aging (85±2℃): elongation at break ≥250%; change in tensile strength ≤±-15%; Change in elongation at break ≤-25%.
Weather resistance test. Sheath low-temperature bending test: the temperature of the refrigerating room is -40±2℃, 16 hours, and there is no crack after the test. The internal insulation and ozone resistance of the sheath: the ozone concentration is 250-300pphm, 24 hours, 180° to ensure that there are no cracks in the bend. The weather resistance of the sheath: spray water for 18 minutes, dry xenon lamp for 102 minutes, test temperature 45±5°C, total test time at least 500 hours, and then perform 7.1 bending test at room temperature without cracks.
Tensile test of internal insulation mechanical properties before aging: tensile strength ≥5N/mm2, elongation at break ≥200%; after aging (135±2℃), the change in tensile strength ≤±30%, elongation at break and elongation Elongation ≤±30%; Air elastic aging tensile test: Change of tensile strength ≤+ 30% at air pressure of 5.5 bar (127°C), change of elongation at break ≤ + 30%; Thermal elongation test: oven in At a temperature of 250±3°C, the elongation under a mechanical pressure under a load of 20 N/cm 2 is 100% or less, and the elongation after unloading is 25% or less.
