Related Resources: hardware

BS EN ISO 4033 Hexagon nuts style 2

Engineering ANSI Hardware Design Data
Engineering Metric Hardware Design Data

BS EN ISO 4033 Hexagon nuts style 2 – product grades A and B

Example for the designation of a hexagon nut with metric thread size d = M12 and property class 9:
Hexagon nut ISO 4033 – M12 – 9

All dimensions are in millimeters.

BS EN ISO 4033 Hex Nuts Table 1 Preferred sizes Dimensions in mm

Thread size, d		M5		M6	M8	M10	M12	(M14)	M16	M20	M24	M30	M36
Pa		0.8		1	1.25	1.5	1.75	2	2	2.5	3	3.5	4
c	max.	0.5		0.5	0.6	0.6	0.6	0.6	0.8	0.8	0.8	0.8	0.8
da	min.	5	6		8	10	12	14	16	20	24	30	36
	max.	5.75	6.75		8.75	10.8	13	15.1	17.3	21.6	25.9	32.4	28.9
dw	min.	6.9	8.9		11.6	14.6	16.6	19.6	22.5	27.7	33.2	42.7	51.1
e	min.	8.79	11.05		14.38	17.77	20.03	23.35	26.75	32.95	39.55	50.85	60.79
m	max.	5.1	5.7		7.5	9.3	12	14.1	16.4	20.3	23.9	28.6	34.7
	min.	4.8	5.4		7.14	8.94	11.57	13.4	15.7	19	22.6	27.3	33.1
m'	min.	3.84	4.32		5.71	7.15	9.26	10.7	12.6	15.2	18.1	21.8	26.5
s	max.	8	10		13	16	18	21	24	30	36	46	55
	min.	7.78	9.78		12.73	15.73	17.73	20.67	23.67	29.16	35	45	53.8

Sizes in brackets should be avoided.

 

Nominal thread diameter (mm)	Width across flats (mm)	Annular bearing area Thread stress area *
5	8	1.08
6	10	1.44
8	13	1.23
10	15	0.90
	16	1.30
	17	1.73
12	18	0.91
	19	1.16
14	21	0.96
	22	1.24
16	24	1.02
20	30	0.95
24	36	0.86
30	46	1.02
36	55	1.04

* Calculation based on clearance holes ISO 273 (revised), medium series.

BS EN ISO 4033 Table 2

Thread size, d		M10		M12	M14
P a		1.5		1.75	2
dw	min.	13.6	15.6	17.4	20.4
e	min.	16.64	18.90	21.10	24.49
m	max.	10	8.8	11.3	13.13
	min.	9.64	8.44	10.87	12.7
m'	min.	7.7	6.75	8.7	10.2
s	max.	15	17	19	22
	min.	14.73	16.73	18.67	21.67

^a P = pitch of the thread.