These bolts has good conductive performance and is generally used for connecting electrical appliances and circuits and also can be used in building industry machinery.
| Screw Thread 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 | max | 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 | 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 | 0.15 | 0.2 | ||
| max | 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 | |||
| da | max | 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 | ||
| dw | Grade A | min | 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 | |
| Grade B | min | - | - | - | - | - | 5.7 | 6.7 | 8.7 | 9.4 | 11.4 | 15.4 | 17.2 | 20.1 | 22 | ||
| e | Grade A | min | 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 | |
| Grade B | min | - | - | - | - | - | 7.5 | 8.63 | 10.89 | 11.94 | 14.2 | 18.72 | 20.88 | 23.91 | 26.17 | ||
| k | Nominal Size | 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 | ||
| Grade A | min | 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 | ||
| max | 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 | |||
| Grade B | min | - | - | - | - | - | 2.6 | 3.26 | 3.76 | 4.56 | 5.06 | 6.11 | 7.21 | 8.51 | 9.71 | ||
| max | - | - | - | - | - | 3 | 3.74 | 4.24 | 5.04 | 5.54 | 6.69 | 7.79 | 9.09 | 10.29 | |||
| k1 | min | 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 | min | 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 size | 3.2 | 4 | 5 | 5.5 | 6 | 7 | 8 | 10 | 11 | 13 | 17 | 19 | 22 | 24 | ||
| Grade A | min | 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 | ||
| Grade B | min | - | - | - | - | - | 6.64 | 7.64 | 9.64 | 10.57 | 12.57 | 16.57 | 18.48 | 21.16 | 23.16 | ||
| Weight of per 1000 steel products(≈kg) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | |||
| Screw Thread 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 | max | 7.5 | 7.5 | 7.5 | 9 | 9 | 10.5 | 10.5 | 12 | 12 | 13.5 | 13.5 | 15 | 15 | - | ||
| c | min | 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 | - | ||
| max | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 1 | 1 | 1 | 1 | 1 | - | |||
| da | max | 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 | - | ||
| dw | Grade A | min | 25.3 | 28.2 | 30 | 33.6 | - | - | - | - | - | - | - | - | - | - | |
| Grade B | min | 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 | - | ||
| e | Grade A | min | 30.14 | 33.53 | 35.72 | 39.98 | - | - | - | - | - | - | - | - | - | - | |
| Grade B | min | 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 Size | 11.5 | 12.5 | 14 | 15 | 17 | 18.7 | 21 | 22.5 | 25 | 26 | 28 | 30 | 33 | - | ||
| Grade A | min | 11.28 | 12.28 | 13.78 | 14.78 | - | - | - | - | - | - | - | - | - | - | ||
| max | 11.72 | 12.72 | 14.22 | 15.22 | - | - | - | - | - | - | - | - | - | - | |||
| Grade B | min | 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 | - | ||
| max | 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 | - | |||
| k1 | min | 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 | min | 0.6 | 0.8 | 0.8 | 0.8 | 1 | 1 | 1 | 1 | 1 | 1.2 | 1.2 | 1.6 | 1.6 | - | ||
| s | max=nominal size | 27 | 30 | 32 | 36 | 41 | 46 | 50 | 55 | 60 | 65 | 70 | 75 | 80 | - | ||
| Grade A | min | 26.67 | 29.67 | 31.61 | 35.38 | - | - | - | - | - | - | - | - | - | - | ||
| Grade B | min | 26.15 | 29.16 | 31 | 35 | 40 | 45 | 49 | 53.8 | 58.8 | 63.1 | 68.1 | 73.1 | 78.1 | - | ||
| Weight of per 1000 steel products(≈kg) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | |||
| ① This standard specifies requirements for M1,6 to M52 hexagon head screws threaded up to the head,assigned to product grade A,for sizes up to M24 and lengths not exceeding 10d or 150 mm,and to product grade B for sizes greater than M24 or lengths exceeding 10 d or 150 mm. | |||||||||||||||||
| ② For thread sizes not greater than M4,also permitted without chamfered end | |||||||||||||||||
| Screw Thread d | 1/4 | 5/16 | 3/8 | 7/16 | 1/2 | 5/8 | 3/4 | 7/8 | 1 | 1-1/8 | 1-1/4 | 1-3/8 | 1-1/2 | |
| d | max | 0.26 | 0.324 | 0.388 | 0.452 | 0.515 | 0.642 | 0.768 | 0.895 | 1.022 | 1.149 | 1.277 | 1.404 | 1.531 |
| min | 0.237 | 0.298 | 0.36 | 0.421 | 0.482 | 0.605 | 0.729 | 0.852 | 0.976 | 1.098 | 1.223 | 1.345 | 1.47 | |
| s | max | 0.438 | 0.5 | 0.562 | 0.625 | 0.75 | 0.938 | 1.125 | 1.312 | 1.5 | 1.688 | 1.875 | 2.062 | 2.25 |
| min | 0.425 | 0.484 | 0.544 | 0.603 | 0.725 | 0.905 | 1.088 | 1.269 | 1.45 | 1.631 | 1.812 | 1.994 | 2.175 | |
| k | max | 0.188 | 0.235 | 0.268 | 0.316 | 0.364 | 0.444 | 0.524 | 0.604 | 0.7 | 0.78 | 0.876 | 0.94 | 1.036 |
| min | 0.15 | 0.195 | 0.226 | 0.272 | 0.302 | 0.378 | 0.455 | 0.531 | 0.591 | 0.658 | 0.749 | 0.81 | 0.902 | |
| Screw Thread d | 1-5/8 | 1-3/4 | 1-7/8 | 2 | 2-1/4 | 2-1/2 | 2-3/4 | 3 | 3-1/4 | 3-1/2 | 3-3/4 | 4 | - | |
| d | max | 1.658 | 1.785 | 1.912 | 2.039 | 2.305 | 2.559 | 2.827 | 3.081 | 3.335 | 3.589 | 3.858 | 4.111 | - |
| min | 1.591 | 1.716 | 1.839 | 1.964 | 2.214 | 2.461 | 2.711 | 2.961 | 3.21 | 3.461 | 3.726 | 3.975 | - | |
| s | max | 2.438 | 2.625 | 2.812 | 3 | 3.375 | 3.75 | 4.125 | 4.5 | 4.875 | 5.25 | 5.625 | 6 | - |
| min | 2.356 | 2.538 | 2.719 | 2.9 | 3.262 | 3.625 | 3.988 | 4.35 | 4.712 | 5.075 | 5.437 | 5.8 | - | |
| k | max | 1.116 | 1.196 | 1.276 | 1.388 | 1.548 | 1.708 | 1.869 | 2.06 | 2.251 | 2.38 | 2.572 | 2.764 | - |
| min | 0.978 | 1.054 | 1.13 | 1.175 | 1.327 | 1.479 | 1.632 | 1.815 | 1.936 | 2.057 | 2.241 | 2.424 | - | |