scope:

This standard aims at helping test personnel perform the test in an appropriate method by describing the method of evaluating the presence of fracture in nuts and nut threads when applying the stress to the nut(high strength nut for general automobiles) in the tensile or compressive direction under the specified load less than proof yield stress(stress at permanent set limit Rp0.2) full loadability.

This standard specifies the method of proof load test for nuts used for automobiles (thick nuts and reduced loadability nuts)⁽²⁾

Note ¹⁾ Size of nuts shall be M5 or more.

²⁾ Nuts requiring mechanical property regardless of shape, such as hexagon nut, square nut, slotted nut and cap nut.