Hexagon Reduced Head Bolts with Guide Neck Product Grade A, Type 1
GOST 7811 (-1) - 1970 小六角头导颈螺栓 A级，1型
See all versions and complete specifications: Hexagon Reduced Head Bolts with Guide Neck Product Grade A, Type 1 — Full Specification Page
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M6 | 1.25 | 0.6 | 0.15 | 4 | 12 | 1 | 8 | 13.2 | 10.6 | 7.78 | 5 |
| M8 | 1.75 | 0.6 | 0.15 | 6 | 17 | 1.25 | 12 | 18.9 | 15.6 | 11.73 | 7 |
| M10 | 2 | 0.8 | 0.2 | 8 | 22 | 1.5 | 16 | 24.5 | 20.6 | 15.73 | 9 |
| M12 | 2.5 | 0.8 | 0.2 | 10 | 27 |
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| 1.5 |
| 20 |
| 30.1 |
| 25.3 |
| 19.67 |
| 11 |
| M16 | 3.5 | 0.8 | 0.2 | 15 | 41 | 2 | 30 | 45.6 | 38.4 | 29.67 | 17 |
| M20 | 5 | 0.8 | 0.25 | 24 | 70 | 3 | 48 | 78.3 | 65.8 | 47.61 | 26 |
| (M14) | 3 | 0.8 | 0.2 | 12 | 32 | 2 | 24 | 35.7 | 30 | 23.67 | 13 |
| (M18) | 4.5 | 0.8 | 0.25 | 21 | 60 | 3 | 42 | 67 | 56.3 | 41.61 | 23 |
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