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Metric Flat Washers Per. ANSI B18.22M

Engineering ANSI Hardware Design Data
Engineering Metric Hardware Design Data

Metric Plain Washer Designation. When specifying metric plain washers, the designation should include the following data in the sequence shown: description, nominal size, series, material type, and finish, if required.

Example:Plain washer, 6 mm, narrow, soft, steel, zinc plated Plain washer, 10 mm, regular, hardened steel.

Metric Flat Washers Per. ANSI B18.22M

All dimensions are in millimeters.

Nominal Washer Size *	Washer Series	Inside Diameter, A		Outside Diameter, B		Thickness, C
		Max	Min	Max	Min	Max	Min
1.6	Narrow Regular Wide	2.09 2.09 2.09	1.95 1.95 1.95	4.00 5.00 6.00	3.70 4.70 5.70	0.70 0.70 0.90	0.50 0.50 0.60
2	Narrow Regular Wide	2.64 2.64 2.64	2.50 2.50 2.50	5.00 6.00 8.00	4.70 5.70 7.64	0.90 0.90 0.90	0.60 0.60 0.60
2.5	Narrow Regular Wide	3.14 3.14 3.14	3.00 3.00 3.00	6.00 8.00 10.00	5.70 7.64 9.64	0.90 0.90 1.20	0.60 0.60 0.80
3	Narrow Regular Wide	3.68 3.68 3.68	3.50 3.50 3.50	7.00 10.00 12.00	6.64 9.64 11.57	0.90 1.20 1.40	0.60 0.80 1.00
3.5	Narrow Regular Wide	4.18 4.18 4.18	4.00 4.00 4.00	9.00 10.00 15.00	8.64 9.64 14.57	1.20 1.40 1.75	0.80 1.00 1.20
4	Narrow Regular Wide	4.88 4.88 4.88	4.70 4.70 4.70	10.00 12.00 16.00	9.64 11.57 15.57	1.20 1.40 2.30	0.80 1.00 1.60
5	Narrow Regular Wide	5.78 5.78 5.78	5.50 5.50 5.50	11.00 15.00 20.00	10.57 14.57 19.48	1.40 1.75 2.30	1.00 1.20 1.60
6	Narrow Regular Wide	6.87 6.87 6.87	6.65 6.65 6.65	13.00 18.80 25.40	12.57 18.37 24.88	1.75 1.75 2.30	1.20 1.20 1.60
8	Narrow Regular Wide	9.12 9.12 9.12	8.90 8.90 8.90	18.80** 25.40** 32.00	18.37** 24.48** 31.38	2.30 2.30 2.80	1.60 1.60 2.00
10	Narrow Regular Wide	11.12 11.12 11.12	10.85 10.85 10.85	20.00 28.00 39.00	19.48 27.48 38.38	2.30 2.80 3.50	1.60 2.00 2.50
12	Narrow Regular Wide	13.57 13.57 13.57	13.30 13.30 13.30	25.40 34.00 44.00	24.88 33.38 43.38	2.80 3.50 3.50	2.00 2.50 2.50
14	Narrow Regular Wide	15.52 15.52 15.52	15.25 15.25 15.25	28.00 39.00 50.00	27.48 38.38 49.38	2.80 3.50 4.00	2.00 2.50 3.00
16	Narrow Regular Wide	17.52 17.52 17.52	17.25 17.25 17.25	32.00 44.00 56.00	31.38 43.38 54.80	3.50 4.00 4.60	2.50 3.00 3.50
20	Narrow Regular Wide	22.32 22.32 22.32	21.80 21.80 21.80	39.00 50.00 66.00	38.38 49.38 64.80	4.00 4.60 5.10	3.00 3.50 4.00
24	Narrow Regular Wide	26.12 26.12 26.12	25.60 25.60 25.60	44.00 56.00 72.00	43.38 54.80 70.80	4.60 5.10 5.60	3.50 4.00 4.50
30	Narrow Regular Wide	33.02 33.02 33.02	32.40 32.40 32.40	56.00 72.00 90.00	54.80 70.80 88.60	5.10 5.60 6.40	4.00 4.50 5.00
36	Narrow Regular Wide	38.92 38.92 38.92	38.30 38.30 38.30	66.00 90.00 110.00	64.80 88.60 108.60	5.60 6.40 8.50	4.50 5.00 7.00

* Nominal washer sizes are intended for use with comparable screw and bolt sizes.

** The 18.80 ⁄18.37 and 25.40 ⁄24.48 mm outside diameters avoid washers which could be used in coin-operated devices.