ISO 10511 M18 Nylon insert lock nut
ISO 10511 M18 is a nylon insert lock nut, on a M18 × 1.5 mm metric thread. ISO equivalent of DIN 985. Reuse is limited — the prevailing torque drops each time the insert is run over the thread.
Dimensions
- Standard
- ISO 10511
- Type
- Nylon insert lock nut
- Size
- M18
- Thread
- M18 × 1.5
- Socket size s
- 27 mm
- Height m
- 21 mm
- Total height h
- 23 mm
- Drive
- External hexagon
Nominal values in millimetres as published in ISO 10511. Estimated weight 36.105 g per piece in steel (36.335 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.
Thread data
Full M18 thread pageOther lengthsISO 10511 M18
All M18 specificationsInterchangeability
ISO 10511 is catalogued with DIN 985 as its equivalent designation. Dimensions are compared field by field rather than assumed identical.
Choosing and fitting this size
ISO 10511 M18 is a M18 nut, on a 1.5 mm coarse pitch. Mating threads should be a matching class nut in the same property class.
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, M18 × 1.5 mm takes a 16.5 mm tap drill, and the external thread's minor diameter is 16.16 mm — that is the section carrying the load, not the nominal M18 figure. Thread engagement of at least one times the nominal diameter is what lets the bolt fail before the thread strips.