GOST 4751-73 Eye Bolt, Bolt with Eye, Bolt with Ring

State Standard of the Union of Soviet Socialist Republics

EYE BOLTS

Technical specifications

Screw rings. Specifications

Effective date 1974-07-01

INFORMATIONAL DATA

1. APPROVED AND PUT INTO EFFECT by Decree of the State Committee for Standards of the Council of Ministers of the USSR dated 10.05.73 No. 1169

2. Review deadline - 1993, frequency - 5 years

3. SUPERSEDES GOST 4751-67

4. REFERENCE REGULATORY AND TECHNICAL DOCUMENTS

Designation of the referenced regulatory document	Clause number
GOST 9.014-78	5.6
GOST 9.301-86	2.15, 3.1
GOST 9.302-88	4.6
GOST 515-77	5.3
GOST 1050-88	2.1
GOST 1759.0-87	215
GOST 2991-85	5.3
GOST 7505-89	2.3
GOST 9012-59	4.2
GOST 10549-80	2.10
GOST 14192-96	5.8
GOST 15150-69	Introductory part
GOST 16093-81	2.10, appendix
GOST 24705-81	2.10, appendix

5. Reviewed in 1988. The validity period limitation was removed by Decree of the USSR State Standards Committee dated 16.12.88 No. 4162

6. REISSUE (June 1998) with Amendments No. 1, 2, 3, 4, approved in May 1979, January 1983, December 1988, August 1990 (IUS 7-79, 5-83, 3-89, 11-90)

The standard applies to eye bolts intended for lifting, lowering or holding products suspended during installation and rigging work, for all operating conditions per GOST 15150.

1. MAIN PARAMETERS AND DIMENSIONS

1.1. The design and main dimensions of eye bolts shall comply with those shown in the drawing and in Table 1.

Table 1

Dimensions in mm

Thread designation	Application									, not less than			Mass of 1 pc., kg
M8		36	20	8	20	10	12	6	18	12		4	0.05
M10		45	25	10	25	12	16	8	21	15	2		0.12
M12		54	30	12	30	14	18	10	25	19		6	0.19
M16		63	35	14	36	16	20	12	32	25			0.31
M20		72	40	16	40	19	24	14	38	29		8	0.50
M24		90	50	20	50	24	29	16	45	35	3	12	0.87
M30		108	60	24	63	28	37	18	55	44		15	1.58
M36		126	70	28	75	32	43	22	63	51		18	2.43
M42		144	80	32	85	38	50	25	72	58	4	20	3.72
M48		162	90	36	95	42	52	30	82	68		22	5.54
M56		180	100	40	105	48	60	34	95	78		25	8.09
M64		198	110	44	115	52	65	40	110	93			10.95
M72×6		234	130	52	135	62	75	45	115	98	5	35	18.54
M80×6		270	150	60	160	70	88	50	125	108			25.40
M100×6		324	180	72	190	85	105	60	150	133		40	43.82

Example of designation of an eye bolt with M8 thread, without coating:

Eye bolt M8 GOST 4751-73

Same, with fine thread M100×6, with coating 01 (zinc with chromate conversion), thickness 9 µm:

Eye bolt M 100×6.019 GOST 4751-73

1.2. The load capacity of eye bolts shall comply with the values specified in Table 2.

Table 2

Thread designation	Load capacity per 1 eye bolt, kg, +
	with sling direction
	along the vertical axis of the eye bolt	at an angle of 45° from the vertical axis of the eye bolt
		in the plane of the ring	with deviation from the plane of the ring
M8	120	80	40
M10	200	125	65
M12	300	175	90
M16	550	250	125
M20	850	325	150
M24	1250	500	250
M30	2000	700	350
M36	3000	1000	500
M42	4000	1300	650
M48	5000	1650	800
M56	6200	2000	1000
M64	7500	2500	1250
M72×6	10000	3500	1750
M80×6	14000	4500	2250
M100×6	20000	6500	3250

Notes:

1. When lifting a load, the sling direction shall not deviate from the vertical axis of the eye bolt by more than 45°.

2. To align the rings of two eye bolts screwed in to the full depth in one plane, flat washers of the following thickness may be used:

• up to 1 mm - for eye bolts with M8-M12 thread;

• no more than half the thread pitch - for eye bolts with thread over M12.

1.3. The design and dimensions of sockets for eye bolts are given in the appendix.

2. Technical requirements

2.1. Eye bolts are made of steel grade 20 or 25 (subgroup a) per GOST 1050 by stamping. Manufacture by forging is also permitted.

Conformity of the material to the specified grades shall be confirmed by a certificate from the metal manufacturer.

2.3. Technical requirements for stamped forgings per GOST 7505, accuracy class - II, complexity degree - C3.

Note. When eye bolts are manufactured by open-die forging in backing dies, positive tolerances may be increased by a factor of 2.

2.4. A flat spot on the inner circumference of the ring, resulting from deburring, is permitted provided the dimension remains within the tolerances of clause 2.3.

2.5. Welding or filling of defects is not permitted.

2.6. After stamping or forging, eye bolts are normalized and cleaned of scale.

2.7. The hardness of normalized eye bolts shall comply with that specified in Table 3.

Table 3

	Hardness HB of eye bolts with thread size
Steel grade	from M8 to M64	from M72×6 to M100×6
20	105-149	95-121
25	134-187	105-149

One repeat heat treatment is permitted.

2.8. Center holes on the ring of the eye bolt are not permitted.

2.9. Notches on the machined part of the shank are not permitted.

2.10. Thread per GOST 24705 with 8g tolerance class per GOST 16093. Chamfer and thread runout dimensions per GOST 10549. The thread runout value for the tool entry angle is 20°.

Note. When a coating is applied, the specified dimensions and surface roughness shall be maintained.

2.11. The thread shall not have stripped threads, burrs or dents.

2.12. Perpendicularity tolerance of the thread axis over a length of 100 mm relative to the bearing plane of the ring:

0.10 mm - for eye bolts with thread from M8 to M16;

0.05 mm from M20 to M100×6.

2.13. Symmetry tolerance of the thread axis relative to the common planes of symmetry of the eye bolt:

T 1 mm - for eye bolts with thread from M8 to M12;

T 2 mm from M16 to M48;

T 4 mm from M56 to M100×6.

2.14. Eye bolts shall withstand a strength test under a load equal to twice the nominal load capacity.

The permissible deviation of this load is ±5%.

2.15. Eye bolts may be manufactured with a coating. Types and designations of coatings per GOST 1759.0.

Technical requirements for coatings and surface quality of eye bolts prior to coating per GOST 9.301.

3. ACCEPTANCE RULES

3.1. Acceptance tests of eye bolts are conducted as follows. During acceptance tests, eye bolts are checked:

before machining:

• for compliance with the requirements of clause 1.1 regarding dimensions obtained by die stamping or forging, and clauses 2.3, 2.4: in the case of open-die forging in backing dies - every eye bolt; in the case of die stamping - 5% of the lot, but not fewer than 5 pcs;

• for compliance with the requirements of clauses 2.5 and 2.6 - every eye bolt;

• for compliance with the requirements of clause 2.7 - 10% of the lot, but not fewer than 5 pcs;

after machining:

• for compliance with the requirements of clause 1.1 (dimensions , and and ) and clauses 2.8-2.14 - every eye bolt;

• for compliance with the requirements of clause 2.15 - per GOST 9.301.

Note. A lot consists of eye bolts of one size, made of steel of one grade, that have undergone heat treatment together.

3.2. If unsatisfactory test results are obtained for eye bolts on at least one parameter, repeat tests are carried out on double the number of samples taken from the same lot, following the full test program. The results of the repeat tests are final and apply to the entire lot.

4. TEST METHODS

4.1. Compliance with the requirements of clause 2.3 is checked by visual inspection without the use of magnifying devices.

The use of magnifying glasses of up to 3x magnification is permitted.

4.2. Hardness (clause 2.7) is determined per GOST 9012 on the generating line of the bearing part of the ring.

4.3. The thread (clause 2.10) is checked using limit gauges.

4.4. The deviation from perpendicularity of the threaded shank axis to the bearing surface of the ring (clause 2.12) is checked using an angle gauge or a feeler gauge, based on the gap of light between the bearing surface of the ring and the end face of the control gauge.

4.5. Compliance of eye bolts with the requirements of clause 2.4 is checked by a tensile test with a 10-minute hold under load.

The load shall be applied along the axis of the eye bolt shank.

The load shall be applied smoothly, without jerking.

After the load is removed, the eye bolts shall show no residual deformation, cracks or tears.

Absence of residual deformation is determined by checking the dimensions along the axis of the eye bolts before and after testing.

Absence of cracks and tears is checked by visual inspection using a magnifying glass with at least 4x magnification.

4.6. The coating thickness (clause 2.15) is checked on the ring of the eye bolt. Methods for checking coating quality and thickness - according to GOST 9.302.

5. MARKING, PACKAGING, TRANSPORTATION AND STORAGE

5.1. Each eye bolt is marked on the generating line of the supporting part of the ring with the following:

• trademark of the manufacturer;

• thread designation.

For eye bolts with M8-M16 thread, it is permitted to mark only the manufacturer’s trademark; in this case, the thread designation is marked on the tag for the batch.

5.2. Marking is performed by pressing or stamping. Marking by impact method is permitted.

5.3. Eye bolts are packed in solid non-collapsible wooden boxes according to GOST 2991, lined inside with grade B packing paper according to GOST 515.

5.4. Each box contains eye bolts from a single batch.

5.5. The gross weight of each box must not exceed 60 kg.

5.6. Preservation - according to GOST 9.014.

5.7. Each batch of eye bolts is accompanied by a document containing:

• name or trademark of the manufacturer;

• designation of the eye bolts;

• quantity of eye bolts;

• results of inspection tests.

5.8. Marking of transport packaging - according to GOST 14192.

5.9. Each box is marked with:

• trademark of the manufacturer;

• designation of the eye bolts;

• gross and net weight in kilograms.

APPENDIX (Recommended)

SOCKETS FOR EYE BOLTS

1. The design and dimensions of sockets for eye bolts in ferrous metal products must comply with those indicated in the drawing and table.

mm

Thread designation			, not less than
M8	13	5	19
M10	15	6	22
M12	17		26
M16	22	7	33
M20	28	9	39
M24	32	10	47
M30	38	11	57
M36	45	12	65
M42	52	14	74
M48	60		84
M56	68		97
M64	75		112
M72×6	85	17	117
M80×6	95		127
M100×6	115		152

2. Thread - according to GOST 24705 with tolerance class H according to GOST 16093. The thread must not have torn threads.

3. Perpendicularity tolerance of the thread axis over a length of 100 mm relative to the supporting surface of the socket:

0.2 mm - for eye bolts with M8 to M16 thread;

0.1 mm - for eye bolts with M20 to M100×6 thread.

4. Sockets for eye bolts must be clean, without cavities and undercuts.

5. The dimension of the flat supporting surface of the socket, with a surface roughness designation of Ra 12.5 μm, must be not less than the diameter of the supporting surface of the eye bolt.

Complies with DIN 580 and ISO 3266.