scope:

This standard covers material and performance requirements applicable to Types D, F and T (thread cutting) tapping screws, heat treated to achieve properties comparable to GMSOOM (9.8) metric screws and GM275M inch screws with induction hardened points, in sizes 5 mm (10 in.) and larger, which are suitable for use in general engineering and structural attachments.

NOTE: This specification is intended to supersede GM specification GM6170M(A) for metric Types D, F and T tapping screws in the 6 through 12 mm sizes.

When selecting the length of screw for any application, it should be an objective to locate the induction hardened zone beyond the exit side of the mating component as depicted in Figure 1, or to maintain a minimum length of thread engagement equal to four full form noninduction hardened threads as illustrated in Figure 2.

The performance values specified in this standard are not valid for design use unless all conditions of the application are identical to the combination of laboratory conditions described in the testing procedure.