Screw Thread d				M4	M5	M6	(M7)	M8	M10	M12	(M14)	M16	(M18)	M20	(M22)	M24	(M27)	M30	(M33)	M36	(M39)	M42	(M45)	M48	(M52)
P		Pitch		0.7	0.8	1	1	1.25	1.5	1.75	2	2	2.5	2.5	2.5	3	3	3.5	3.5	4	4	4.5	4.5	5	5
a		max		2.1	2.4	3	3	3.75	4.5	5.25	6	6	7.5	7.5	7.5	9	9	10.5	10.5	12	12	13.5	13.5	15	15
c		min		0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.3	0.3	0.3	0.3	0.3
		max		0.4	0.5	0.5	0.5	0.6	0.6	0.6	0.6	0.8	0.8	0.8	0.8	0.8	0.8	0.8	0.8	0.8	1	1	1	1	1
da		max		4.7	5.7	6.8	7.8	9.2	11.2	13.7	15.7	17.7	20.2	22.4	24.4	26.4	30.4	33.4	36.4	39.4	42.4	45.6	48.6	52.6	56.6
dw		Grade A	min	5.9	6.9	8.9	9.6	11.6	15.6	17.4	20.5	22.5	25.3	28.2	30	33.6	-	-	-	-	-	-	-	-	-
		Grade B	min	5.7	6.7	8.7	9.4	11.4	15.4	17.2	20.1	22	24.8	27.7	29.5	33.2	38	42.7	46.5	51.1	55.9	59.9	64.7	69.4	74.2
e		Grade A	min	7.66	8.79	11.05	12.12	14.38	18.9	21.1	24.49	26.75	30.14	33.53	35.72	39.98	-	-	-	-	-	-	-	-	-
		Grade B	min	7.5	8.63	10.89	11.94	14.2	18.72	20.88	23.91	26.17	29.56	32.95	35.03	39.55	45.2	50.85	55.37	60.79	66.44	71.3	76.95	82.6	88.25
k		Nominal Size		2.8	3.5	4	4.8	5.3	6.4	7.5	8.8	10	11.5	12.5	14	15	17	18.7	21	22.5	25	26	28	30	33
		Grade A	min	2.68	3.35	3.85	4.65	5.15	6.22	7.32	8.62	9.82	11.28	12.28	13.78	14.78	-	-	-	-	-	-	-	-	-
			max	2.92	3.65	4.15	4.95	5.45	6.56	7.68	8.98	10.18	11.72	12.72	14.22	15.22	-	-	-	-	-	-	-	-	-
		Grade B	min	2.6	3.26	3.76	4.56	5.06	6.11	7.21	8.51	9.71	11.15	12.15	13.65	14.65	16.65	18.28	20.58	22.08	24.58	25.58	27.58	29.58	32.5
			max	3	3.74	4.24	5.04	5.54	6.69	7.79	9.09	10.29	11.85	12.85	14.35	15.35	17.35	19.12	21.42	22.92	25.42	26.42	28.42	30.42	33.5
k1		min		1.9	2.28	2.63	3.19	3.54	4.28	5.05	5.96	6.8	7.8	8.5	9.6	10.3	11.7	12.8	14.4	15.5	17.2	17.9	19.3	20.9	22.8
r		min		0.2	0.2	0.25	0.25	0.4	0.4	0.6	0.6	0.6	0.6	0.8	0.8	0.8	1	1	1	1	1	1.2	1.2	1.6	1.6
s		max=nominal size		7	8	10	11	13	17	19	22	24	27	30	32	36	41	46	50	55	60	65	70	75	80
		Grade A	min	6.78	7.78	9.78	10.73	12.73	16.73	18.67	21.67	23.67	26.67	29.67	31.61	35.38	-	-	-	-	-	-	-	-	-
		Grade B	min	6.64	7.64	9.64	10.57	12.57	16.57	18.48	21.16	23.16	26.15	29.16	31	35	40	45	49	53.8	58.8	63.1	68.1	73.1	78.1

Related Knowlege : The material comes from a china state-owned big steel manufacturer, which can issue an authoritative material inspection report for 35 #, 45 #, 345B, 40Cr, 35CrmoA, and other special materials. This guarantee the required hardness and screw torque and other mechanical characters.