Overview
The most common material classification system used in O-ring specification is probably "Standard Classification System for Rubber Products in Automotive Applications." or ASTM D 2000. This system is designed to aid in the selection of practical rubber products for specific environments and provides a "line call-out" designation for the specification of elastomer seal materials.
How to read an ASTM D 2000 Line Call-Out
Specification Revision
ASTM-D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31, EO88, F15, Z1
This indicates the revision year of 02000 to which the line call-out makes reference.
Measurement Units
ASTM D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31, EO88, F15, Z1
If an M is present, metric units will be used for tensile strength, temperature, and tear strength (MPa, °C, and kN/m respectively). If no M is present, English units will be used (psi, °F, and ppi respectively).
Grade Number
ASTM D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31, EO88, F15, Z1
Indicates the level of test requirements to which a material may be subjected. For example, Grade 1 shows that only
basic properties are required, while Grades 2-9 require additional testing criteria such as low temperature brittleness or special heat aging tests. In our example, we will be looking at a fluorocarbon material that must meet some or all Grade 2 requirements. Note that Grade Numbers may not be relevant to all material Types and Classes.