標準號：SIS SS-ISO 6157-3-1992
中文標準名稱：緊固件．表面不連續性．第3部分：特殊要求的螺釘、螺桿及柱頭螺栓
英文標準名稱：Fasteners — Surface discontinuities — Part 3: Bolts, screws and studs for special requirements
發布日期：1992/9/30 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：1 This part of ISO 6157 establishes limits for various types of surface discontinuities on bolts, screws and studs for special requirements.It applies to bolts, screws and studs with— nominal thread diameters 5 mm and larger;— product grades A and B;— nominal lenghts / < 10d (or longer if specified);— property dass 12.9;— property classes 8.8, 9.8 and 10.9 when specified in product standards or agreed between supplier and purchaser.2 Where the permissible limits for surface discontinuities indicated in clause 3 occur, the minimum values for the mechanical and functional proparties specified in ISO 898-1 should still be met.When fatigue strength requirements are specified, the fatigue strength should not be lower than that obtained on bolts without defects taken from the same lot.NOTES3 The figures in clause 3 are examples only. They apply correspond-ingly also to other types of bolts, screws and studs.4 The individual figures show the surface discontinuities exaggerated in some cases for clarity.