Standard | JT/T4-2004 | BS5400 Section 9.2 | |||
Rubber | Natural Rubber | Neoprene CR | Natural Rubber | Neoprene CR | |
Hardness(IRHD) | 60±5 | 60±5 | 50±5/60±5/70±5 | ||
Tensile Strength (M Pa)≥ | 18 | 17 | 17 | 15.5 | |
Ultimate Elongation (%)≥ | 450 | 400 | 450/400/350 | 400/350/300 | |
Compression Set | 70 o C×22h | 70 o C×22h | 100 o C×22h | ||
<30 | <15 | <30 | <35 | ||
Heat Resistance | Test Condition | 70 o C×168h | 100 o C×70h | 70 o C×168h | 100 o C×48h |
Change in Hardness | -5,+10 | 0,+10 | <10 | <15 | |
(IRHD) | |||||
Rate of Tensile Strength Reduction(%) | <15 | <15 | |||
Rate of Ultimate | <20 | <40 | <20 | <40 | |
Elongation Reduction | |||||
(%) | |||||
Ozone Resistance | 25~50pphm,20% strain | 25~50pphm,20% strain | |||
40 o C×96h | 30 o C×96h | ||||
No Cracks | No Cracks |