Original
By certification 
| Thread specification | M1.6 | M2 | M2.5 | M3 | (M3.5) | M4 | M5 | M6 | M8 | M10 | M12 | (M14) | M16 | (M18) | M20 | (M22) | M24 | (M27) | M30 | (M33) | M36 | (M39) | M42 | (M45) | M48 | (M52) | M56 | (M60) | M64 | |||
| d | ||||||||||||||||||||||||||||||||
| P | pitch | 0.35 | 0.4 | 0.45 | 0.5 | 0.6 | 0.7 | 0.8 | 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 | 5.5 | 5.5 | 6 | ||
| a | Max | 1.05 | 1.2 | 1.35 | 1.5 | 1.8 | 2.1 | 2.4 | 3 | 4 | 4.5 | 5.3 | 6 | 6 | 7.5 | 7.5 | 7.5 | 9 | 9 | 10.5 | 10.5 | 12 | 12 | 13.5 | 13.5 | 15 | 15 | 16.5 | 16.5 | 18 | ||
| Min | 0.35 | 0.4 | 0.45 | 0.5 | 0.6 | 0.7 | 0.8 | 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 | 5.5 | 5.5 | 6 | |||
| c | Max | 0.25 | 0.25 | 0.25 | 0.4 | 0.4 | 0.4 | 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 | 1 | 1 | 1 | ||
| Min | 0.1 | 0.1 | 0.1 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.2 | 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 | 0.3 | 0.3 | 0.3 | |||
| da | Max | 2 | 2.6 | 3.1 | 3.6 | 4.1 | 4.7 | 5.7 | 6.8 | 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 | 63 | 67 | 71 | ||
| dw | Class A | Min | 2.27 | 3.07 | 4.07 | 4.57 | 5.07 | 5.88 | 6.88 | 8.88 | 11.63 | 14.63 | 16.63 | 19.64 | 22.49 | 25.34 | 28.19 | 31.71 | 33.61 | - | - | - | - | - | - | - | - | - | - | - | - | |
| Class B | Min | 2.3 | 2.95 | 3.95 | 4.45 | 4.95 | 5.74 | 6.74 | 8.74 | 11.47 | 14.47 | 16.47 | 19.15 | 22 | 24.85 | 27.7 | 31.35 | 33.25 | 38 | 42.75 | 46.55 | 51.11 | 55.86 | 59.95 | 64.7 | 69.45 | 74.2 | 78.66 | 83.41 | 88.16 | ||
| e | Class A | Min | 3.41 | 4.32 | 5.45 | 6.01 | 6.58 | 7.66 | 8.79 | 11.05 | 14.38 | 17.77 | 20.03 | 23.36 | 26.75 | 30.14 | 33.53 | 37.72 | 39.98 | - | - | - | - | - | - | - | - | - | - | - | - | |
| Class B | Min | 3.28 | 4.18 | 5.31 | 5.88 | 6.44 | 7.5 | 8.63 | 10.89 | 14.2 | 17.59 | 19.85 | 22.78 | 26.17 | 29.56 | 32.95 | 37.29 | 39.55 | 45.2 | 50.85 | 55.37 | 60.79 | 66.44 | 71.3 | 76.95 | 82.6 | 88.25 | 93.56 | 99.21 | 104.86 | ||
| k | Nominal | 1.1 | 1.4 | 1.7 | 2 | 2.4 | 2.8 | 3.5 | 4 | 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 | 35 | 38 | 40 | ||
| Class A | Max | 1.225 | 1.525 | 1.825 | 2.125 | 2.525 | 2.925 | 3.65 | 4.15 | 5.45 | 6.58 | 7.68 | 8.98 | 10.18 | 11.715 | 12.715 | 14.215 | 15.215 | - | - | - | - | - | - | - | - | - | - | - | - | ||
| Min | 0.975 | 1.275 | 1.575 | 1.875 | 2.275 | 2.675 | 3.35 | 3.85 | 5.15 | 6.22 | 7.32 | 8.62 | 9.82 | 11.285 | 12.285 | 13.785 | 14.785 | - | - | - | - | - | - | - | - | - | - | - | - | |||
| Class B | Max | 1.3 | 1.6 | 1.9 | 2.2 | 2.6 | 3 | 3.74 | 4.24 | 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 | 35.5 | 38.5 | 40.5 | ||
| Min | 0.9 | 1.2 | 1.5 | 1.8 | 2.2 | 2.6 | 3.26 | 3.76 | 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 | 34.5 | 37.5 | 39.5 | |||
| k1 | Class A | Min | 0.68 | 0.89 | 1.1 | 1.31 | 1.59 | 1.87 | 2.35 | 2.7 | 3.61 | 4.35 | 5.12 | 6.03 | 6.87 | 7.9 | 8.6 | 9.65 | 10.35 | - | - | - | - | - | - | - | - | - | - | - | - | |
| Class B | Min | 0.63 | 0.84 | 1.05 | 1.26 | 1.54 | 1.82 | 2.28 | 2.63 | 3.54 | 4.28 | 5.05 | 5.96 | 6.8 | 7.81 | 8.51 | 9.56 | 10.26 | 11.66 | 12.8 | 14.41 | 15.46 | 17.21 | 17.91 | 19.31 | 20.71 | 22.75 | 24.15 | 26.25 | 27.65 | ||
| r | Min | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | 0.2 | 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 | 2 | 2 | 2 | ||
| s | Max=nominal | 3.2 | 4 | 5 | 5.5 | 6 | 7 | 8 | 10 | 13 | 16 | 18 | 21 | 24 | 27 | 30 | 34 | 36 | 41 | 46 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | ||
| Class A | Min | 3.02 | 3.82 | 4.82 | 5.32 | 5.82 | 6.78 | 7.78 | 9.78 | 12.73 | 15.73 | 17.73 | 20.67 | 23.67 | 26.67 | 29.67 | 33.38 | 35.38 | - | - | - | - | - | - | - | - | - | - | - | - | ||
| Class A | Min | 2.9 | 3.7 | 4.7 | 5.2 | 5.7 | 6.64 | 7.64 | 9.64 | 12.57 | 15.57 | 17.57 | 20.16 | 23.16 | 26.16 | 29.16 | 33 | 35 | 40 | 45 | 49 | 53.8 | 58.8 | 63.1 | 68.1 | 73.1 | 78.1 | 82.8 | 87.8 | 92.8 | ||
| Thousand pieces of steel weight≈kg | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | ||
With the increase in the scope of bolts, bolts can be divided into different grades. There are 4.8, 6.8, 8.8, 10.9, 12.9, 8.8 bolts and above bolts are called high-strength bolts, and high-strength bolts have construction comparisons. It is simple, has better mechanical performance, and can be disassembled and replaced, and it will not loosen under dynamic load. The best anti-corrosion treatment for high-strength bolts is hot-dip galvanizing. Manufactured by Handan Fastener Co., Ltd.
The surface treatment process of hot-dip galvanizing is: loading→pickling, water washing→solvent→drying→hot-dip galvanizing→internal and external blowing→rolling label, marking→passivation→inspection→packaging. The thickness of the zinc layer is more than 50μm, and the hot-dip galvanizing surface treatment can reach at least 15 years without rust in use. It has good coverage and no organic impurities. In terms of resistance to atmospheric corrosion, the surface of the zinc layer is attached with a protective film formed by ZnO, Zn(OH)2 and basic zinc carbonate, which can slow down to a certain extent. Corrosion of the zinc layer by the atmosphere. Hot-dip galvanized surface treatment also has the following advantages: 1. Lower processing cost, 2. Durable and durable, 3. Reliability is better, 4. Comprehensive protection, 5. Time saving and labor saving, 6. Comparison of the toughness of the coating good.
Grade 8.8 hot-dip galvanized bolts are high-strength bolts. Compared with ordinary bolts, the tensile capacity of high-strength bolts will be improved. Bolts with different materials or origins have the same performance, which indicates the nominal tensile strength value and yield ratio of the material used for the bolt. The meaning of the 8.8 bolt is: its nominal tensile strength can be It reaches 800MPa level, and the yield strength ratio is 0.8, so it can be seen that its nominal yield strength can reach 800×0.8=640MPa level.
The material of grade 8.8 hexagon bolts is mainly 35# and 45#. According to the diameter of the 8.8 grade bolt, the material used will also change accordingly. The material below M16 is 35#, and the material of bolts above M16 is 45. #. In order for people to better distinguish between ordinary bolts and high-strength bolts, whether it is a full-buckle bolt or a half-buckle bolt, the surface is treated to be boiled black blue.
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