ISO 4762 M20 × 100 Socket head (cylindrical)
ISO 4762 M20 × 100 is a socket head cap screw with a 100 mm nominal length, on a M20 × 1.5 mm metric thread. The ISO version of the metric socket head cap screw. Dimensionally very close to DIN 912, with small differences in nominal head height across some sizes.
Dimensions
- Standard
- ISO 4762
- Type
- Socket head cap screw
- Size
- M20 × 100
- Thread
- M20 × 1.5
- Length L
- 100 mm
- Socket size s
- 17 mm
- Head diameter dk
- 30 mm
- Head height k
- 20 mm
- Thread length b
- 52 mm
- Drive
- Hexagon socket
- Head
- Socket head (cylindrical)
Nominal values in millimetres as published in ISO 4762. Estimated weight 357.592 g per piece in steel (359.869 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M20 thread pageOther lengthsISO 4762 M20
All M20 specificationsInterchangeability
ISO 4762 is catalogued with DIN 912 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.
Choosing and fitting this size
ISO 4762 M20 × 100 is a socket head (cylindrical) in M20, 100 mm long under the head, on a 1.5 mm coarse pitch. Mating threads should be a matching class nut or a tapped hole of the same nominal size.
Common stock grades are 8.8, 10.9 and 12.9 in steel, plus A2-70 and A4-80 in stainless. Class 10.9 and 12.9 carry roughly 1.25 and 1.5 times the proof load of 8.8, but they also need a properly rated mating nut — a class 8 nut under a 12.9 bolt simply moves the failure into the thread. Zinc-plated 10.9 and above should be baked to avoid hydrogen embrittlement.
For a tapped hole, M20 × 1.5 mm takes a 18.5 mm tap drill, and the external thread's minor diameter is 18.16 mm — that is the section carrying the load, not the nominal M20 figure. Thread engagement of at least one times the nominal diameter is what lets the bolt fail before the thread strips.