ISO Metric Pitch Thread Proof Loads

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The table below shows proof loads for bolts, nuts and studs with an ISO metric coarse and fine pitch thread in sizes M3 to M39.

According to EN ISO 898-1.

a Where no thread pitch is indicated in a thread designation, coarse pitch is specified.


b To calculate As,nom, see


c For fasteners with thread tolerance 6az in accordance with ISO 965-4 subject to hot dip galvanizing, reduced values in accordance with ISO 10684:2004, Annex A, apply.


d For structural bolting 50 700 N (for M12), 68 800 N (for M14) and 94 500 N (for M16).

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