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Grade 8.8 Hex Head Bolts

Name: Grade 8.8 Hex Head Bolts
Brand: Befast Co., Ltd.

Grade 8.8 hex head bolts are a step up in terms of strength, offering higher tensile strength compared to Grade 4.8. They are commonly used in heavy machinery, automotive, and structural applications, where a stronger fastening solution is required.

These bolts are made from carbon steel with heat treatment for added strength and durability. Grade 8.8 bolts provide superior resistance to stress and fatigue, making them ideal for demanding environments.

Products

Specifications of Grade 8.8 Hex Head Bolts

Name	Hex Bolts	Materials	Carbon Steel/Stainless Steel
Standards	DIN ISO ANC BSW JIS etc.	Strength level	4.8 8.8 10.9 12.9 A2-70 A4-70 A4-80
Size	M3-M50	Surface finish	ZP\HDG\BLACK\Dacromet etc.
Length	15-500	Samples	Available

Grade 8.8 Hex Head Bolts Dimension

Hexagon Head Thick Shank Half Thread Bolts M1.6-M39 DIN 931

thread size			M1.6	M2	M2.5	M3	(M3.5)	M4	M5	M6	(M7)	M8	M10	M12
d			M1.6	M2	M2.5	M3	(M3.5)	M4	M5	M6	(M7)	M8	M10	M12
P	pitch		0.35	0.4	0.45	0.5	0.6	0.7	0.8	1	1	1.25	1.5	1.75
b	Reference	L≤125	9	10	11	12	13	14	16	18	20	twenty two	26	30
		125＜L≤200	-	-	-	-	-	-	twenty two	twenty four	26	28	32	36
		L＞200	-	-	-	-	-	-	-	-	-	-	45	49
c	minimum		0.1	0.1	0.1	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15
c	maximum value		0.25	0.25	0.25	0.4	0.4	0.4	0.5	0.5	0.5	0.6	0.6	0.6
d _a	maximum value		2	2.6	3.1	3.6	4.1	4.7	5.7	6.8	7.8	9.2	11.2	13.7
d_s	max = nominal		1.6	2	2.5	3	3.5	4	5	6	7	8	10	12
	minimum	Class A	1.46	1.86	2.36	2.86	3.32	3.82	4.82	5.82	6.78	7.78	9.78	11.73
	minimum	Class B	-	-	-	-	-	-	-	-	-	-	-	-
d_w	minimum	Class A	2.4	3.2	4.1	4.6	5.1	5.9	6.9	8.9	9.8	11.6	15.6	17.4
d_w	minimum	Class B	-	-	-	-	-	-	-	-	-	-	-	-
and	minimum	Class A	3.41	4.32	5.45	6.01	6.58	7.66	8.79	11.05	12.12	14.38	18.9	21.1
and	minimum	Class B	-	-	-	-	-	-	-	-	-	-	-	-
k	Nominal		1.1	1.4	1.7	2	2.4	2.8	3.5	4	4.8	5.3	6.4	7.5
	Class A	minimum	0.98	1.28	1.58	1.88	2.28	2.68	3.35	3.85	4.65	5.15	6.22	7.32
	Class A	maximum value	1.22	1.52	1.82	2.12	2.52	2.92	3.65	4.15	4.95	5.45	6.58	7.68
	Class B	minimum	-	-	-	-	-	-	-	-	-	-	-	-
	Class B	maximum value	-	-	-	-	-	-	-	-	-	-	-	-
k ₁	minimum		0.7	0.9	1.1	1.3	1.6	1.9	2.28	2.63	3.19	3.54	4.28	5.05
r	minimum		0.1	0.1	0.1	0.1	0.1	0.2	0.2	0.25	0.25	0.4	0.4	0.6
s	max = nominal		3.2	4	5	5.5	6	7	8	10	11	13	17	19
	minimum	Class A	3.02	3.82	4.82	5.32	5.82	6.78	7.78	9.78	10.73	12.73	16.73	18.67
	minimum	Class B	-	-	-	-	-	-	-	-	-	-	-	-
thread length b			-	-	-	-	-	-	-	-	-	-	-	-

thread size			(M14)	M16	(M18)	M20	(M22)	M24	(M27)	M30	(M33)	M36	(M39)
d			(M14)	M16	(M18)	M20	(M22)	M24	(M27)	M30	(M33)	M36	(M39)
P	pitch		2	2	2.5	2.5	2.5	3	3	3.5	3.5	4	4
b	Reference	L≤125	34	38	42	46	50	54	60	66	72	78	84
		125＜L≤200	40	44	48	52	56	60	66	72	78	84	90
		L＞200	53	57	61	65	69	73	79	85	91	97	103
c	minimum		0.15	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.2	0.3
c	maximum value		0.6	0.8	0.8	0.8	0.8	0.8	0.8	0.8	0.8	0.8	1
d _a	maximum value		15.7	17.7	20.2	22.4	24.4	26.4	30.4	33.4	36.4	39.4	42.4
d_s	max = nominal		14	16	18	20	twenty two	twenty four	27	30	33	36	39
	minimum	Class A	13.73	15.73	17.73	19.67	21.67	23.67	-	-	-	-	-
	minimum	Class B	-	15.57	17.57	19.48	21.48	23.48	26.48	29.48	32.38	35.38	38.38
d_w	minimum	Class A	20.5	22.5	25.3	28.2	30	33.6	-	-	-	-	-
d_w	minimum	Class B	-	twenty two	24.8	27.7	29.5	33.2	38	42.7	46.6	51.1	55.9
and	minimum	Class A	24.49	26.75	30.14	33.53	35.72	39.98	-	-	-	-	-
and	minimum	Class B	-	26.17	29.56	32.95	35.03	39.55	45.2	50.85	55.37	60.79	66.44
k	Nominal		8.8	10	11.5	12.5	14	15	17	18.7	twenty one	22.5	25
	Class A	minimum	8.62	9.82	11.28	12.28	13.78	14.78	-	-	-	-	-
	Class A	maximum value	8.98	10.18	11.72	12.72	14.22	15.22	-	-	-	-	-
	Class B	minimum	-	9.71	11.15	12.15	13.65	14.65	16.65	18.28	20.58	22.08	24.58
	Class B	maximum value	-	10.29	11.85	12.85	14.35	15.35	17.35	19.12	21.42	22.92	25.42
k ₁	minimum		5.96	6.8	7.8	8.5	9.6	10.3	11.7	12.8	14.4	15.5	17.2
r	minimum		0.6	0.6	0.6	0.8	0.8	0.8	1	1	1	1	1
s	max = nominal		twenty two	twenty four	27	30	32	36	41	46	50	55	60
	minimum	Class A	21.67	23.67	26.67	29.67	31.61	35.38	-	-	-	-	-
	minimum	Class B	-	23.16	26.16	29.16	31	35	40	45	49	53.8	58.8
thread length b			-	-	-	-	-	-	-	-	-	-	-

Full Thread Hexagon Head Bolts Grade A and B DIN 933

Thread specification			M1.6	M2	M2.5	M3	(M3.5)	M4	M5	M6	(M7)	M8	M10	M12	(M14)	M16
d			M1.6	M2	M2.5	M3	(M3.5)	M4	M5	M6	(M7)	M8	M10	M12	(M14)	M16
P	pitch		0.35	0.4	0.45	0.5	0.6	0.7	0.8	1	1	1.25	1.5	1.75	2	2
a	maximum value		1.05	1.2	1.35	1.5	1.8	2.1	2.4	3	3	3.75	4.5	5.25	6	6
c	minimum		0.1	0.1	0.1	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.2
c	maximum value		0.25	0.25	0.25	0.4	0.4	0.4	0.5	0.5	0.5	0.6	0.6	0.6	0.6	0.8
d _a	maximum value		2	2.6	3.1	3.6	4.1	4.7	5.7	6.8	7.8	9.2	11.2	13.7	15.7	17.7
d_w	Class A	minimum	2.4	3.2	4.1	4.6	5.1	5.9	6.9	8.9	9.6	11.6	15.6	17.4	20.5	22.5
d_w	Class B	minimum	-	-	-	-	-	5.7	6.7	8.7	9.4	11.4	15.4	17.2	20.1	twenty two
and	Class A	minimum	3.41	4.32	5.45	6.01	6.58	7.66	8.79	11.05	12.12	14.38	18.9	21.1	24.49	26.75
and	Class B	minimum	-	-	-	-	-	7.5	8.63	10.89	11.94	14.2	18.72	20.88	23.91	26.17
k	Nominal		1.1	1.4	1.7	2	2.4	2.8	3.5	4	4.8	5.3	6.4	7.5	8.8	10
	Class A	minimum	0.98	1.28	1.58	1.88	2.28	2.68	3.35	3.85	4.65	5.15	6.22	7.32	8.62	9.82
	Class A	maximum value	1.22	1.52	1.82	2.12	2.52	2.92	3.65	4.15	4.95	5.45	6.56	7.68	8.98	10.18
	Class B	minimum	-	-	-	-	-	2.6	3.26	3.76	4.56	5.06	6.11	7.21	8.51	9.71
	Class B	maximum value	-	-	-	-	-	3	3.74	4.24	5.04	5.54	6.69	7.79	9.09	10.29
k ₁	minimum		0.7	0.9	1.1	1.3	1.6	1.9	2.28	2.63	3.19	3.54	4.28	5.05	5.96	6.8
r	minimum		0.1	0.1	0.1	0.1	0.1	0.2	0.2	0.25	0.25	0.4	0.4	0.6	0.6	0.6
s	max = nominal		3.2	4	5	5.5	6	7	8	10	11	13	17	19	twenty two	twenty four
	Class A	minimum	3.02	3.82	4.82	5.32	5.82	6.78	7.78	9.78	10.73	12.73	16.73	18.67	21.67	23.67
	Class B	minimum	-	-	-	-	-	6.64	7.64	9.64	10.57	12.57	16.57	18.48	21.16	23.16
Thousand pieces of steel weight ≈kg			-	-	-	-	-	-	-	-	-	-	-	-	-	-

Thread specification			(M18)	M20	(M22)	M24	(M27)	M30	(M33)	M36	(M39)	M42	(M45)	M48	(M52)
d			(M18)	M20	(M22)	M24	(M27)	M30	(M33)	M36	(M39)	M42	(M45)	M48	(M52)
P	pitch		2.5	2.5	2.5	3	3	3.5	3.5	4	4	4.5	4.5	5	5
a	maximum value		7.5	7.5	7.5	9	9	10.5	10.5	12	12	13.5	13.5	15	15
c	minimum		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
c	maximum value		0.8	0.8	0.8	0.8	0.8	0.8	0.8	0.8	1	1	1	1	1
d _a	maximum value		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
d_w	Class A	minimum	25.3	28.2	30	33.6	-	-	-	-	-	-	-	-	-
d_w	Class B	minimum	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
and	Class A	minimum	30.14	33.53	35.72	39.98	-	-	-	-	-	-	-	-	-
and	Class B	minimum	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		11.5	12.5	14	15	17	18.7	twenty one	22.5	25	26	28	30	33
	Class A	minimum	11.28	12.28	13.78	14.78	-	-	-	-	-	-	-	-	-
	Class A	maximum value	11.72	12.72	14.22	15.22	-	-	-	-	-	-	-	-	-
	Class B	minimum	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
	Class B	maximum value	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
k ₁	minimum		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	minimum		0.6	0.8	0.8	0.8	1	1	1	1	1	1.2	1.2	1.6	1.6
s	max = nominal		27	30	32	36	41	46	50	55	60	65	70	75	80
	Class A	minimum	26.67	29.67	31.61	35.38	-	-	-	-	-	-	-	-	-
	Class B	minimum	26.15	29.16	31	35	40	45	49	53.8	58.8	63.1	68.1	73.1	78.1
Thousand pieces of steel weight ≈kg			-	-	-	-	-	-	-	-	-	-	-	-	-

Benifits of Grade 8.8 Hex Head Bolts

Befast’s Grade 8.8 hex head bolts are engineered for enhanced strength and reliability. We use state-of-the-art manufacturing techniques to produce bolts that can handle higher load-bearing capacities, ensuring your projects stay secure and durable under stress.
Our expert quality control team ensures each bolt meets stringent mechanical, corrosion, and performance tests. With high-volume production capabilities, we deliver large quantities of Grade 8.8 bolts quickly and efficiently, maintaining excellent consistency and value.

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