scope:

This part of ISO 6157 establishes limits for various types of surface discontinuities on bolts, screws and studs for general requirements. It applies to bolts, screws and studs with - nominal thread diameters 5 mm and larger; - products grades A and B; - property classes up to and including 10.9 unless otherwise specified in product standards or agreed between supplier and purchaser. Limits for surface discontinuities for special requirements (e.g. automatic assembly) are laid down in ISO 6157-3. Where the permissible limits for surface discontinuities indicated in clause 3 occur, the minimum values for the mechanical and functional properties specified in ISO 898-1 should still be met.