ISO 6916-2 Standard
The latest version of this standard is ISO 6916-2:2024, which replaces the previous (2001) edition. It specifically addresses molded and extruded cellular (sponge/foamed) rubber products.
Scope
This standard applies to vulcanized cellular rubber products made from natural rubber, reclaimed rubber, synthetic rubber, or similar materials. It explicitly excludes thermoplastic rubbers, latex foam rubber, and materials intended for shoe soles. Covered manufacturing processes include molding or continuous vulcanization (e.g., via hot air, microwave, infrared, or liquid curing medium [LCM] methods).
Classification System (Key Details)
In the context of your previous reference to "2A5," the classification logic of ISO 6916-2 is as follows:
Types:
Type 1: Open-cell rubber.
Type 2: Closed-cell rubber.
Type 3: Integral-skin cellular rubber.
Classes: Divided into A, B, C, and D.
Class A: No specific requirement for resistance to petroleum-based oils (typically made from natural rubber).
Classes B/C: Require resistance to oils (low/medium swelling).
Class D: Made from synthetic rubber, focusing on resistance to high and low temperatures (-75°C to +250°C), with no specific requirement for oil resistance. (Note: EPDM materials, which you previously mentioned, generally align with the application logic of this class in terms of weather and temperature resistance.)
Grades: Classified from 0 to 6 based on compression deflection (hardness). Grade 5 corresponds to a compression deflection range of 125.1 kPa to 200.0 kPa.
Standard Structure
The main body of the standard covers: classification, materials and processes, physical property requirements, test methods, dimensional tolerances, inspection and rejection criteria, as well as packaging and marking. Normative annexes provide specific test methods for properties such as temperature resistance, compression deflection, oil resistance, fluid resistance, and low-temperature performance.