Loading Port:Shanghai
Payment Terms:TT OR LC
Min Order Qty:-
Supply Capability:1000000kgs kg/month
Description
Grade 4255G is silane XLPE compound with monosil method (one step), it is specially used for 10kv below aerial hanging power cable, it is composed by selected PE resin, gray anti-ageing masterbatch and other additives. The product’s major characteristics are
◆Outstanding anti-ageing property
◆Outstanding electrical property
◆Simple processing technique
Standard
After crosslinked in the tepid water, the cable made from the product grade 4255G can comply with the standard of IEC60502-2004, GB/T14049-2008
Main Properties & Typical Values
Test Items | Unit | Test Method | Standard | Typical value |
Tensile strength | MPa | GB/T1040.3 | ≥13.5 | 18.5 |
Elongation at break | % | GB/T1040.3 | ≥300 | 460 |
Heat ageing properties (Test temperature 135℃, 168hr) Maximum tensile strength change Maximum elongation at break change |
% % | GB/T8815 |
±20 ±20 |
7.2 7.5 |
Heat elongation （200±3)℃x15minx0.2MPa) Maximum elongation change under load Maximum permanent elongation change after cooled |
% % | GB/T2951 |
≤80 ≤5 |
60 2 |
Impact brittle temp. (-76℃) Impact brittle | Failure no. | GB/T5470 |
≤15/30 |
Pass* |
Dielectric Strength | MV/m | GB/T1408.1 | ≥30 | 40* |
Dielectric loss factor 50Hz, 20℃ | -- | GB/T1409 | ≤1×10-4 | 2×10-4* |
Dielectric constant 50Hz, 20℃ | -- | GB/T1409 | ≤2.35 | 2.2* |
Volume resistance (20℃) | Ω·m | GB/T1410 | ≥1.0×1014 | 6×1014* |
Pressure crack test F50 | hr | GB/T2951 | 1000 | Pass* |
Artificial atmosphere ageing properties: Ageing After 42days, Maximum tensile strength change Maximum elongation at break change Ageing after 42days vs. after 21days Maximum tensile strength change Maximum elongation at break change |
% %
% % | GB/T14049 |
±30 ±30
±15 ±15 |
-18 -20
-10 -9 |
Typical values were tested onthe sample strip by squeezing film extrusion and be boiled in hot water at 90℃ for four hours.
*Especially, these typical values were tested by press moulding sample (A and B mixed at percentage of 90:10), under the condition of 180±2 ℃, 15min, and pressure over 15Mpa, then boiled in 90℃ water for four hours.
Recommended Processing Technique
1. Extrusion Equipment
Most extruders for PVC and PE suit for 4255G
The recommended equipment and processing technique is as following.
Ratio of length and diameter 18—25:1
Diameter 45—120mm
Ratio of compressing 1.5—3.5
Ratio of elongation 1:1.0—1:1.5
Filtering mesh 40/60/40
2. Extruder processing temperature and other related settings
Temperature Setting: Specific processing temperature should be based on different equipment and pressing conditions, reference settings are as following:
Feeding Section（℃） | Compression Section（℃） | Measurement Section （℃） | Die head and Mould （℃） |
140~155 | 155~175 | 175~195 | 195~205 |
Die head setting: Tubing extrusion style is recommended.
3. Crosslink
After extrusion and cooling, the cable can be crosslinked by immersed in hot water (90℃) or exposed in low pressure vapour. The time required for crosslink is based on the thickness of the insulation and the coil size, the thicker the insulation and the greater the coil size, the longer the crosslink time required. The crosslink time can be calculated according to the equation of 4hr/mm for 90℃.
