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Bearing locknuts KM, DIN 981 / ISO 2982-2: KM0–KM10 (M10×0.75–M50×1.5) outside diameter, width, slots

Name: Bearing locknuts KM, DIN 981 / ISO 2982-2: KM0–KM10 (M10×0.75–M50×1.5) outside diameter, width, slots dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What are the KM locknut (DIN 981) dimensions, from KM0 M10×0.75 to KM10 M50×1.5? · Standard part · basis: Schaeffler and NTN catalogue pages for KM0, KM1, KM2 (main dimensions to DIN 981), Kramp and FAG listings for KM10, KM12, KM15, KM23, and SKF KM series values for the remaining sizes

Also called: km0 locknut dimensions, km4 lock nut m20x1, din 981 km nut size chart, km6 m30x1.5 nut od, bearing lock nut slot width, km10 m50 locknut 70 mm

Exact dimensions. Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part. Mating features

sizes: 11 in table

Notes

Columns: designation, thread G, outside d2, chamfer diameter d1, width B, slot width b, slot depth h. Four slots, 30° chamfer on one face (Schaeffler). Use with MB lock washers (DIN 5406).
Verified on the maker pages read: KM0 (d2 18, d1 13.5, B 4, b 3), KM1 (22, 17, 4, 3, h 2), KM2 (25, 21, 5, 4, h 2), KM10 (70 × 11). KM3–KM9 are SKF catalogue values; check a maker drawing before relying on d1 or h for those.
Files: thread as a plain bore at the major diameter, as for the other nuts on Xem.

Bearing locknuts KM, DIN 981 / ISO 2982-2: KM0–KM10… size chart

size	thread	d2	d1	B	b	h
KM0	M10x0.75	18	13.5	4	3	2
KM1	M12x1	22	17	4	3	2
KM2	M15x1	25	21	5	4	2
KM3	M17x1	28	24	5	4	2
KM4	M20x1	32	26	6	4	2
KM5	M25x1.5	38	32	7	5	2
KM6	M30x1.5	45	38	7	5	2
KM7	M35x1.5	52	44	8	5	2
KM8	M40x1.5	58	50	9	6	2.5
KM9	M45x1.5	65	56	10	6	2.5
KM10	M50x1.5	70	61	11	6	2.5

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
thread (plain bore at the major Ø)	G: M10×0.75 (KM0) to M50×1.5 (KM10)	shaft thread of the same G; seats against the bearing inner ring or a spacer	designed	all
4 slots on the outside	b wide × h deep (KM0 3 × 2, KM10 10 × 3)	hook spanner, and the outer tab of an MB lock washer (DIN 5406, same number) bent into one slot	designed	all

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Schaeffler	KM0 locknut, main dimensions to DIN 981: G, d2, B, d1, b	web	Publisher's page; dimensions are facts
Schaeffler	KM2 locknut, main dimensions to DIN 981	web	Publisher's page; dimensions are facts
Acorn Industrial	KM 9 locknut: M45×1.5, 65 mm OD, 10 mm wide	web	Publisher's page; dimensions are facts

Free files

★ Free files 11 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

km0	KM0 M10x0.75: Ø18 × 4, 4 slots 3×2, thread as Ø10 bore	STEP · STL
km1	KM1 M12x1: Ø22 × 4, 4 slots 3×2, thread as Ø12 bore	STEP · STL
km2	KM2 M15x1: Ø25 × 5, 4 slots 4×2, thread as Ø15 bore	STEP · STL
km3	KM3 M17x1: Ø28 × 5, 4 slots 4×2, thread as Ø17 bore	STEP · STL
km4	KM4 M20x1: Ø32 × 6, 4 slots 4×2, thread as Ø20 bore	STEP · STL
km5	KM5 M25x1.5: Ø38 × 7, 4 slots 5×2, thread as Ø25 bore	STEP · STL
km6	KM6 M30x1.5: Ø45 × 7, 4 slots 5×2, thread as Ø30 bore	STEP · STL
km7	KM7 M35x1.5: Ø52 × 8, 4 slots 5×2, thread as Ø35 bore	STEP · STL
km8	KM8 M40x1.5: Ø58 × 9, 4 slots 6×2.5, thread as Ø40 bore	STEP · STL
km9	KM9 M45x1.5: Ø65 × 10, 4 slots 6×2.5, thread as Ø45 bore	STEP · STL
km10	KM10 M50x1.5: Ø70 × 11, 4 slots 6×2.5, thread as Ø50 bore	STEP · STL

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Plain text: sheet.txt · JSON: /api/geometry?object=bearing-locknuts-km-din-981