AS568 is a standard for the use of O-rings as sealing elements for aviation. The standard is of American origin and is published by the SAE (Society of Automotive Engineers). AS568 has a broad regulatory scope and provides comprehensive specifications for the handling of O-rings. It mainly relates to the following areas:
Dimensions (inner diameter and cord thicknesses)
Tolerances
Naming
AS568 defines dimensions in the imperial system.
#1 Definition of table AS568
AS568 is a standard for dimensions, tolerances and designation of standardized O-rings. The standard originally referred to aviation as a field of application, but has developed into a general standard.
#2 Meaning of table AS568
O-rings according to the AS568 inch size table are available in many different materials. Together with DIN 3771 for metric dimensions, the standard covers the majority of O-ring applications worldwide.
Both standards have been incorporated into the international standard ISO 3601, which also regulates installation spaces, surface deviations and materials.