This series of product is produced according to requirements of national standard GB7594.7-87 and complies with the provisions of the coal industry standard MT818-2009.
Indicator requirements and measured performance| Test item | Unit | HJ-1 | HJ-2 | HJ-3 | ||||
| Standard requirements | Typical values | Standard requirements | Standard requirements | Typical values | Standard requirements | |||
| Initial tensile strength | Mpa | ≥5.0 | 6.5 | ≥5.0 | 7.5 | ≥4.2 | 8.0 | |
| Elongation at break | % | ≥250 | 280 | ≥250 | 290 | ≥200 | 240 | |
| Thermal aging of air box | Conditions | 75±2℃×240h | 80±2℃×240h | 135±2℃×168h | ||||
| Tensile strength change rate | % | ±30 | +8 | ±30 | +9.0 | ±30 | +10.0 | |
| Change rate of elongation at break | % | ±30 | -8 | ±30 | -10.0 | ±30 | -15.7 | |
| Thermal extension test | Conditions | 200±2℃× 15 min×0.2MPa | 250±3℃× 15 min×0.2MPa min×0.2MPa min×0.2MPa | |||||
| Elongation under load | % | ≤175 | 75 | ≤175 | 68 | ≤175 | 68 | |
| Permanent deformation after cooling | % | ≤25 | 18 | ≤20 | 15 | ≤15 | 11 | |
| Volume resistivity at 20℃ | Ω﹒m | ≥1.0×1013 | 5.5×1013 | ≥1.0×1014 | 7.2×1014 | ≥1.0×1015 | 6.7×1015 | |
| Dielectric strength | MV/m | 26 | 28 | 28 | ||||
| Ozone resistance | Conditions | 250±2℃× 24h ×0.025~0.03% | ||||||
| Results | No cracks | No cracks | ||||||