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Bolt Nut Fastener Force Conversion Table

Socket/Grub Screws Tightening Torques

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This table shows the maximum permissible tightening torques of hexagon and hexalobular socket and flat head screws.

For guidance only

Maximum Tightening Torques (Nm)ISO 4026 / DIN 913 ISO 4027 / DIN 914 ISO 4028 / DIN 915
Screw StandardDIN 6912DIN 7894ISO 7379DIN 7991ISO 14581DIN 7991ISO 7380ISO 7380ISO 4029 / DIN 916
Material / Grade8.8A2-70
A4-70
8.8A2-70
A4-70
12.910.98.8A2-70
A4-70
10.9A2-70
A4-70
45 H *A2 A4
Thread Size
M3--10.6-110.510.50.50.2
M42121.2-2212110.5
M56442.54552.54231.5
M695859994.58452.5
M820121272515-8126105
M10402435214040-2030152010
M12654050307065-3360304522
M1411066---100-50--4522
M1618011011066200110-55--9045
M18----------14070
M20280170200120400150-75--14070
M22----------220110
M24--390235-400-200--220110

* The mechanical characteristics and property classes according to ISO 898 Pt 5 are valid for headless screws not subjected to tensile forces.

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