1.1 This classification system tabulates the properties of vulcanized rubber materials (natural rubber, reclaimed rubber, synthetic rubbers, alone or in combination) that are intended for, but not limited to, use in rubber products for automotive applications.
Note: This classification system may serve many of the needs of other industries in much the same manner as SAE numbered steels. It must be remembered, however, that this system is subject to revision when required by automotive needs. It is recommended that the latest revision always be used.
1.2 This classification system is based on the premise that the properties of all rubber products can be arranged into characteristic material designations. These designations are determined by types, based on resistance to heat aging, and classes, based on resistance to swelling in oil. Basic levels are thus established which, together with values describing additional requirements, permit complete description of the quality of all elastomeric materials.
1.3 In all cases where the provisions of this classification system would conflict with those of the detailed specifications for a particular product, the latter shall take precedence.
Note: When the rubber product is to be used for purposes where the requirements are too specific to be completely prescribed by this classification system, it is necessary for the purchaser to consult the supplier in advance, to establish the appropriate properties, test methods, and specification test limits.
1.4 The values stated in SI units are to be regarded as the standard.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition applies.
GB/T 528 Rubber, vulcanized or thermoplastic - Determination of tensile stress-strain properties (eqv ISO 37)
GB/T 529 Rubber vulcanized or thermoplastic - Determination of tear strength (trouser, angle and crescent test pieces) (eqv ISO 34)
GB/T 531 Rubber - Determination of indentation hardness by means of pocket hardness meters (idt ISO 7619:1986)
GB/T 1687 Rubber, vulcanized - Determination of temperature rise and resistance to fatigue in flexometer testing - Part 2: Compression flexometer (neq ISO 4666/3)
GB/T 1690 Rubber, vulcanized - Determination of the effect of liquids (neq ISO 1817)
GB/T 2941 Rubber - Standard temperatures, humidities and times for the conditioning environmental and testing of test pieces (eqv ISO 471)
GB/T 3512 Rubber, vulcanized or thermoplastic - Accelerated ageing and heat resistance tests - Air-oven method (eqv ISO 188)
GB/T 6036 Rubber, vulcanized or thermoplastic - Determination of low temperature stiffening (Gehman test) (eqv ISO 1432)
GB/T 7042 Rubber properties determination in compression or shear (Yerzley mechanical oscillograph) (eqv ASTM D 945)
GB/T 7757 Rubber, vulcanized or thermoplastic - Determination of compression stress-strain properties (eqv ISO 7743)
GB/T 7758 Rubber, vulcanized - Determination of low-temperature characteristics - Temperature-retraction procedure (TR test) (eqv ISO 2921)
GB/T 7759 Rubber, vulcanized or thermoplastic - Determination of compression set at ambient, elevated or low temperatures (eqv ISO 815)
GB/T 7760 Rubber vulcanized - Determination of adhesion to metal - One-plate method (eqv ISO 813)
GB/T 9865.1 Rubber, vulcanized or thermoplastic - Preparation of samples and test pieces - Part 1: Physical tests (idt ISO 4661-1)
