ISO International Standard

ISO 15172:2005 specifies a test method to evaluate the strength of the nut seat of wheels intended for use on passenger cars, light trucks and multi-purpose vehicles. While this test ensures the minimum strength of the nut seat, the wheel must also have a degree of flexibility to allow torque retention. This test evaluates the axial strength of the nut seat. In addition, an informative annex provides recommended bearing area to ensure enough strength for the rotational force in tightening a nut against the nut seat.