GOST 7798-70 Hexagon Head Bolts, Product Grade B

Hexagon head bolts, product grade B. Design and dimensions.

GOST 7798-70

(ST SEV 4728-84)

Hexagon bolts, product grade B. Construction and dimensions

Effective date 01.07.72

1. This standard applies to hexagon head bolts, product grade B, with thread diameter from 6 to 48 mm.

This standard fully complies with ST SEV 4728-84.

(Amended, Amendment No. 4).

2. The design and dimensions of bolts shall conform to those shown in the drawing and in Tables 1 and 2.

(Amended, Amendments No. 2-6).

3. Thread — per GOST 24705. Thread runout and incomplete thread — per GOST 27148. Bolt ends — per GOST 12414.

(Amended, Amendment No. 5).

3a. Radius under the head — per GOST 24670.

3b. Tolerances of dimensions, form and location deviations of surfaces, and inspection methods not established by this standard — per GOST 1759.1.

3c. Permissible surface defects of bolts and inspection methods — per GOST 1759.2.

3a—3c. (Added, Amendment No. 4).

4. (Deleted, Amendment No. 4).

5. Head design variants are established by the manufacturer.

5a. Bolts may be manufactured with the diameter of the plain shank portion d₁ approximately equal to the pitch diameter of the thread.

(Added, Amendment No. 3).

5b. For marking purposes, bolts of design 1 and 2 may be manufactured with a recess on the end face of the head, with dimensions that do not reduce the strength of the head, provided the recess depth does not exceed 0.4 k.

(Added, Amendment No. 5).

6. Technical requirements — per GOST 1759.0.

7. (Deleted, Amendment No. 2).

8. The mass of bolts is given in Appendix 1.

Table 1

Nominal thread diameter, d		6	8	10	12	(14)	16	(18)	20	(22)	24	(27)	30	36	42	48
Thread pitch	coarse	1	1.25	1.5	1.75	2		2.5			3		3.5	4	4.5	5
	fine	-	1	1.25		1.5					2			3
Shank diameter d₁		6	8	10	12	14	16	18	20	22	24	27	30	36	42	48
Width across flats S		10	13	16	18	21	24	27	30	34	36	41	46	55	65	75
Head height k		4.0	5.3	6.4	7.5	8.8	10.0	12.0	12.5	14.0	15.0	17.0	18.7	22.5	26.0	30.0
Circumscribed circle diameter e, min		10.9	14.2	17.6	19.9	22.8	26.2	29.6	33.0	37.3	39.6	45.2	50.9	60.8	71.3	82.6
dw, min		8.7	11.5	14.5	16.5	19.2	22.0	24.8	27.7	31.4	33.2	38.0	42.7	51.1	59.9	69.4
hw	min	0.15					0.20								0.25
	max	0.6					0.8
Diameter of hole in shank d₃		1.6	2.0	2.5	3.2		4.0			5.0			6.3		8.0
Diameter of hole in head d₄ H15		2.0	2.5		3.2		4.0							5.0
Distance from bearing surface to axis of hole in head l₂ js15		2.0	2.8	3.5	4.0	4.5	5.0	6.0	6.5	7.0	7.5	8.5	9.5	11.5	13.0	15.0

Notes:

1. Bolt dimensions shown in parentheses are not recommended for use.

2. Bolts may be manufactured with dimensions specified in Appendix 2.

Table 2

mm

Bolt length, l	Thread length b and distance from the head bearing surface to the axis of the hole in the shank l₁ at nominal thread diameter d (bolts with thread over the full shank length are marked with ×)
	6		8		10		12		(14)		16		(18)		20		(22)		24		(27)		30		36		42		48
	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b	l₁	b
8	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
10	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
12	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
14	10	×	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
16	12	×	12	×	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
(18)	14	×	14	×	14	×	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
20	16	×	16	×	16	×	15	×	-	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
(22)	18	18	18	×	18	×	17	×	17	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
25	21	18	21	×	21	×	20	×	20	×	19	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-	-	-
(28)	24	18	24	22	24	×	23	×	23	×	22	×	22	×	-	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-
30	26	18	26	22	26	×	25	×	25	×	24	×	24	×	24	×	-	×	-	-	-	-	-	-	-	-	-	-	-	-
(32)	28	18	28	22	28	26	27	×	27	×	26	×	26	×	26	×	25	×	-	×	-	-	-	-	-	-	-	-	-	-
35	31	18	31	22	31	26	30	30	30	×	29	×	29	×	29	×	28	×	28	×	-	×	-	-	-	-	-	-	-	-
(38)	34	18	34	22	34	26	33	30	33	×	32	×	32	×	32	×	31	×	31	×	-	×	-	-	-	-	-	-	-	-
40	36	18	36	22	36	26	35	30	35	34	34	×	34	×	34	×	33	×	33	×	32	×	-	×	-	-	-	-	-	-
45	41	18	41	22	41	26	40	30	40	34	39	38	39	×	39	×	38	×	38	×	37	×	36	×	-	-	-	-	-	-
50	46	18	46	22	46	26	45	30	45	34	44	38	44	42	44	×	43	×	43	×	42	×	41	×	40	×	-	-	-	-
55	51	18	51	22	51	26	50	30	50	34	49	38	49	42	49	46	48	×	48	×	47	×	46	×	45	×	-	×	-	-
60	56	18	56	22	56	26	55	30	55	34	54	38	54	42	54	46	53	50	53	×	52	×	51	×	50	×	48	×	-	-
65	61	18	61	22	61	26	60	30	60	34	59	38	59	42	59	46	58	50	58	54	57	×	56	×	55	×	53	×	-	-
70	66	18	66	22	66	26	65	30	65	34	64	38	64	42	64	46	63	50	63	54	62	60	61	×	60	×	58	×	58	×
75	71	18	71	22	71	26	70	30	70	34	69	38	69	42	69	46	68	50	68	54	67	60	66	66	65	×	63	×	63	×
80	76	18	76	22	76	26	75	30	75	34	74	38	74	42	74	46	73	50	73	54	72	60	71	66	70	×	68	×	68	×
(85)	81	18	81	22	81	26	80	30	80	34	79	38	79	42	79	46	78	50	78	54	77	60	76	66	75	×	73	×	73	×
90	86	18	86	22	86	26	85	30	85	34	84	38	84	42	84	46	83	50	83	54	82	60	81	66	80	78	78	×	78	×
(95)	-	-	91	22	91	26	90	30	90	34	89	38	89	42	89	46	88	50	88	54	87	60	86	66	85	78	83	×	83	×
100	-	-	96	22	96	26	95	30	95	34	94	38	94	42	94	46	93	50	93	54	92	60	91	66	90	78	88	×	88	×
(105)	-	-	-	-	101	26	100	30	100	34	99	38	99	42	99	46	98	50	98	54	97	60	96	66	95	78	93	90	93	×
110	-	-	-	-	106	26	105	30	105	34	104	38	104	42	104	46	103	50	103	54	102	60	101	66	100	78	98	90	98	×
(115)	-	-	-	-	111	26	110	30	110	34	109	38	109	42	109	46	108	50	108	54	107	60	106	66	105	78	103	90	103	102
120	-	-	-	-	116	26	115	30	115	34	114	38	114	42	114	46	113	50	113	54	112	60	111	66	110	78	108	90	108	102
(125)	-	-	-	-	121	26	120	30	120	34	119	38	119	42	119	46	118	50	118	54	117	60	116	66	115	78	113	90	113	102
130	-	-	-	-	126	32	125	36	125	40	124	44	124	48	124	52	123	56	123	60	122	66	121	72	120	84	118	96	118	108
140	-	-	-	-	136	32	135	36	135	40	134	44	134	48	134	52	133	56	133	60	132	66	131	72	130	84	128	96	128	108
150	-	-	-	-	146	32	145	36	145	40	144	44	144	48	144	52	143	56	143	60	142	66	141	72	140	84	138	96	138	108
160	-	-	-	-	156	32	155	36	155	40	154	44	154	48	154	52	153	56	153	60	152	66	151	72	150	84	148	96	148	108
170	-	-	-	-	166	32	165	36	165	40	164	44	164	48	164	52	163	56	163	60	162	66	161	72	160	84	158	96	158	108
180	-	-	-	-	176	32	175	36	175	40	174	44	174	48	174	52	173	56	173	60	172	66	171	72	170	84	168	96	168	108
190	-	-	-	-	186	32	185	36	185	40	184	44	184	48	184	52	183	56	183	60	182	66	181	72	180	84	178	96	178	108
200	-	-	-	-	196	32	195	36	195	40	194	44	194	48	194	52	193	56	193	60	192	66	191	72	190	84	188	96	188	108
220	-	-	-	-	-	-	215	49	215	57	214	57	214	61	214	65	213	69	213	73	212	79	211	85	210	97	208	109	208	121
240	-	-	-	-	-	-	235	49	235	57	234	57	234	61	234	65	233	69	233	73	232	79	231	85	230	97	228	109	228	121
260	-	-	-	-	-	-	255	49	255	57	254	57	254	61	254	65	254	69	253	73	252	79	251	85	250	97	248	109	248	121
280	-	-	-	-	-	-	-	-	275	57	274	57	274	61	274	65	273	69	273	73	272	79	271	85	270	97	268	109	268	121
300	-	-	-	-	-	-	-	-	295	57	294	57	294	61	294	65	293	69	293	73	292	79	291	85	290	97	288	109	288	121

Notes:

1. Bolts with lengths shown in parentheses are not recommended for use.

2. Bolts for which the values of b are located above the stepped line may be manufactured with thread extending up to the head.

Example of designation of a design 1 bolt with thread diameter d=12 mm, width across flats S=18 mm, length l=60 mm, coarse pitch, tolerance class 6g, property class 5.8, plain:

Bolt M12 — 6g ×60.58 (S18) GOST 7798-70

Same, design 2, with width across flats S=19 mm, fine pitch, tolerance class 6g, property class 10.9, made of steel grade 40Kh, with coating 01, thickness 6 μm:

Bolt 2M12×1.25 — 6g×60.109.40Kh.016 GOST 7798-70

APPENDIX 1

For reference

Mass of steel bolts (design 1) with coarse pitch thread

Bolt length l, mm	Theoretical mass of 1000 bolts, kg, at nominal thread diameter d, mm
	6	8	10	12	14	16	18	20	22	24	27	30	36	42	48
8	4.306	8.668	-	-	-	-	-	-	-	-	-	-	-	-	-
10	4.712	9.394	16.68	-	-	-	-	-	-	-	-	-	-	-	-
12	5.118	10.120	17.82	-	-	-	-	-	-	-	-	-	-	-	-
14	5.524	10.850	18.96	27.89	-	-	-	-	-	-	-	-	-	-	-
16	5.930	11.570	20.10	29.48	43.98	-	-	-	-	-	-	-	-	-	-
18	6.336	12.300	21.23	31.12	46.21	65.54	-	-	-	-	-	-	-	-	-
20	6.742	13.020	22.37	32.76	48.45	68.49	95.81	-	-	-	-	-	-	-	-
22	7.204	13.520	23.51	34.40	50.69	71.44	99.52	-	-	-	-	-	-	-	-
25	7.871	14.840	25.22	36.86	54.05	75.87	105.10	133.3	-	-	-	-	-	-	-
28	8.537	16.330	26.92	39.32	57.40	80.29	110.60	140.2	-	-	-	-	-	-	-
30	8.981	17.120	28.52	40.96	59.64	83.24	114.30	144.8	193.0	-	-	-	-	-	-
32	9.426	17.910	29.43	42.59	61.87	86.19	118.00	149.4	198.6	237.0	-	-	-	-	-
35	10.090	19.090	31.28	45.34	65.24	90.62	123.60	156.3	207.0	246.9	340.6	-	-	-	-
38	10.760	20.280	33.18	48.00	68.59	95.04	129.20	163.2	215.4	256.9	353.3	-	-	-	-
40	11.200	21.070	34.36	49.78	71.25	97.99	132.90	167.8	221.0	263.5	361.8	474.8	-	-	-
45	12.310	23.040	37.45	54.22	77.30	105.70	142.10	179.4	235.0	280.1	373.0	500.9	-	-	-
50	13.420	25.020	40.53	58.67	83.35	113.60	152.40	190.9	249.0	296.7	404.1	526.9	834.5	-	-
55	14.530	26.990	43.62	63.11	89.39	121.50	162.40	203.7	263.1	313.3	425.3	553.0	872.1	1304	-
60	15.640	28.970	46.70	67.55	95.44	129.40	172.40	216.0	278.9	329.9	446.5	579.0	909.8	1356	-
65	16.760	30.940	49.79	71.99	101.50	137.30	182.40	228.4	293.8	348.8	467.7	605.1	947.4	1407	2009
70	17.870	32.910	52.87	76.44	107.50	145.20	192.40	240.7	308.8	366.5	491.1	631.1	985.0	1458	2076
75	18.980	34.890	55.96	80.88	113.60	153.10	202.40	253.0	323.7	384.3	513.6	659.7	1023.0	1509	2143
80	20.090	36.860	59.04	85.33	119.60	161.00	212.40	265.0	338.6	402.1	536.1	687.5	1061.0	1561	2211
85	21.200	38.840	62.13	89.77	125.70	168.90	222.40	277.7	353.6	419.8	558.6	715.2	1098.0	1612	2278
90	22.310	40.810	65.21	94.20	131.70	176.80	232.40	290.1	368.5	437.6	581.0	743.0	1141.0	1663	2345
95	-	42.790	68.30	98.64	137.80	184.70	242.40	302.4	383.4	455.4	603.5	770.8	1181.0	1715	2412
100	-	44.760	71.38	103.10	143.80	192.60	252.40	314.7	398.3	473.2	626.0	798.5	1221.0	1766	2479
105	-	-	74.47	107.50	149.90	200.50	262.40	327.1	413.3	490.9	648.5	826.3	1261.0	1826	2546
110	-	-	77.55	112.00	155.90	208.40	272.30	339.4	428.2	508.7	671.0	854.1	1301.0	1880	2614
115	-	-	80.63	116.40	162.00	216.30	282.30	351.8	443.1	526.5	693.5	881.8	1341.0	1934	2690
120	-	-	83.72	120.90	168.00	224.20	292.30	364.1	458.1	544.2	716.0	909.6	1381.0	1989	2760
125	-	-	86.80	125.30	174.00	232.10	302.30	376.4	473.0	562.0	738.5	937.4	1421.0	2043	2831
130	-	-	89.89	129.70	180.10	240.00	312.30	388.8	487.9	579.8	761.0	965.2	1461.0	2098	2903
140	-	-	96.06	138.60	192.20	255.80	332.30	413.5	517.8	615.3	806.0	1021.0	1541.0	2207	3045
150	-	-	102.18	147.50	204.30	271.60	352.30	438.1	547.6	650.8	850.1	1076.0	1621.0	2315	3187
160	-	-	108.38	156.40	216.40	287.40	372.30	462.8	577.5	686.4	895.9	1132.0	1701.0	2424	3329
170	-	-	114.58	165.30	228.50	303.20	392.30	487.5	607.4	721.9	940.9	1188.0	1780.0	2533	3471
180	-	-	120.68	174.20	240.60	319.00	412.30	512.2	637.2	757.5	985.9	1243.0	1860.0	2642	3614
190	-	-	126.88	183.10	252.70	333.80	432.30	536.9	667.1	793.0	1031.0	1299.0	1940.0	2751	3756
200	-	-	133.08	191.90	264.70	350.60	452.20	561.5	697.0	828.6	1076.0	1354.0	2020.0	2860	3898
220	-	-	-	209.70	228.90	382.20	492.20	610.9	756.7	899.6	1166.0	1465.0	2180.0	3077	4182
240	-	-	-	227.50	313.10	413.80	532.20	660.3	816.4	970.8	1256.0	1576.0	2340.0	3295	4466
260	-	-	-	245.20	337.60	445.40	572.20	709.6	876.1	1042.0	1346.0	1687.0	2500.0	3513	4751
280	-	-	-	-	361.50	476.90	612.20	759.0	935.9	1113.0	1436.0	1798.0	2660.0	3730	5035
300	-	-	-	-	385.70	508.50	652.20	808.3	995.6	1184.0	1526.0	1910.0	2820.0	3948	5319

(Amended, Amendment No. 5)

APPENDIX 2

For reference

Additional requirements reflecting the needs of the national economy

Dimensions in mm

Nominal thread diameter d			10	12	12	22
Width across flats S			17	19	22	32
Circumscribed circle diameter e, min			18.7	20.9	23.9	35.0
dw, min			15.5	17.2	20.1	29.5
Bolt length l	10	Theoretical mass of 1000 bolts (design 1) with coarse pitch thread, kg	18.10	-	-	-
	12		19.24	-	-	-
	14		20.38	29.75	-	-
	16		21.52	31.34	46.52	-
	18		22.65	32.98	48.75	-
	20		23.79	34.62	50.09	-
	22		24.93	36.26	53.23	-
	25		26.64	38.72	56.59	-
	28		28.34	41.18	59.94	-
	30		29.48	42.82	62.18	180.6
	32		30.85	44.45	64.41	186.2
	35		32.70	47.20	67.78	194.6
	38		34.55	49.86	71.13	203.0
	40		35.78	51.64	73.79	208.6
	45		38.87	56.08	79.84	222.6
	50		41.95	60.53	85.89	236.6
	55		45.04	64.97	91.93	250.7
	60		48.12	69.41	97.98	266.5
	65		51.21	73.85	104.00	281.4
	70		54.29	78.30	110.00	296.4
	75		57.38	82.74	116.10	311.3
	80		60.46	87.19	122.10	326.2
	85		63.55	91.63	128.20	341.2
	90		66.63	96.06	134.20	356.1
	95		69.72	100.50	140.30	371.0
	100		72.80	105.00	146.30	385.9
	105		75.89	109.40	152.40	400.9
	110		78.97	113.90	158.40	415.8
	115		82.05	118.30	164.50	430.7
	120		85.14	122.80	170.50	445.7
	125		88.22	127.20	176.50	460.6
	130		91.31	131.60	182.60	475.5
	140		97.48	140.50	194.70	505.4
	150		103.60	149.40	206.80	535.2
	160		109.80	158.30	218.90	565.1
	170		116.00	167.20	231.00	595.0
	180		122.10	176.10	243.10	624.7
	190		128.30	185.00	255.20	654.7
	200		134.50	193.80	267.20	684.6
	220		-	211.60	291.40	744.3
	240		-	229.40	315.60	804.0
	260		-	247.10	339.80	863.7
	280		-	-	364.00	923.5
	300		-	-	388.20	983.2

APPENDIX 2 (Added, Amendment No. 5; amended, Amendment No. 6).

Information data

1. DEVELOPED AND SUBMITTED BY the Ministry of Ferrous Metallurgy of the USSR

DEVELOPERS I. N. Nedoviziy, Candidate of Technical Sciences; B. M. Rigmant; V. I. Mokrinskiy, Candidate of Technical Sciences

2. APPROVED AND PUT INTO EFFECT by Decree No. 270 of the Committee for Standards, Weights and Measuring Instruments under the Council of Ministers of the USSR dated 04.03.70

3. The standard fully complies with ST SEV 4728-84

4. SUPERSEDES GOST 7798-62

5. REFERENCE REGULATORY AND TECHNICAL DOCUMENTS

Designation of the referenced regulatory document	Clause number	Designation of the referenced regulatory document	Clause number
GOST 1759.0-87	6	GOST 24670-81	3a
GOST 1759.1-82	3b	GOST 24705-81	3
GOST 1759.2-82	3v	GOST 27148-86	3
GOST 12414-66	3

6. The expiration restriction was lifted by Protocol No. 5-94 of the Interstate Council for Standardization, Metrology and Certification (IUS 11-12-94).

7. REISSUE with Amendments No. 2, 3, 4, 5, 6, approved in February 1974, March 1981, March 1985, March 1989, July 1995 (IUS 3-74, 6-81, 6-85, 6-89, 9-95).