METRIC 12.9 SOCKET HEAD CAP SCREWS (DIN 912) are typically manufactured from alloy carbon steel, quenched and tempered for strength, usually black oxide (plain) finish. They have a minimum tensile strength of 1220 MPa, (M2 to M48) and generally agreed to be the equivalent to Imperial Grade 8 bolts @ 172000 psi.
This series socket head bolt are identified with a "12.9" marking on the head. Coarse threads are most common. Thread length is formulated at 4 x diameter, or fully threaded for shorter lengths less than the formula. Length is measured from under the head.
The number preceding ".", ie 8.
8, 10.
9, 12.
9 refers to the maximum load that the fastener can handle as a percentage of its ultimate tensile strength, ie: 80 or 90 %. Torquing or loading beyond the safe limit, known as the elastic range causes the fastener to suffer an unrecoverable stretch & deformation resulting in shear or fractional failure.
COARSE THREAD
Click Here for Available Dimensions & LengthsZinc Plate or Fine Thread by special order, ask your rep to confirm availability.
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