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ASME B18.3 (T13):2012 Socket Head Cap Hex Socket Screw
ASME B18.3 (T13):2012 Socket Head Cap Hex Socket Screw combines a hex socket drive with a shoulder structure, making it suitable for fastening points that require reliable clamping, removable maintenance, and standardized assembly. The ASME standard framework suits projects requiring U.S.-standard compatibility and engineering applicability, supporting smooth alignment between engineering drawings, purchasing lists, and quality inspection.
From an assembly perspective, the internal hex socket provides deeper tool engagement, enabling higher assembly torque in compact spaces while reducing external head interference. At the same time, the defined shoulder can serve as a locating, guiding, or rotational bearing surface, while the threaded section provides locking, so the screw can provide stable fastening performance across different sheet thicknesses, appearance requirements, and space limitations.
It is suitable for linkages, guide elements, stamping tools, sliding parts, and assemblies requiring repeatable positioning. For batch assembly, the product can be tailored around workstation tools, tightening torque, visual grade, and packaging method to reduce sorting cost and improve assembly consistency.
Dimensions unit: inch
|
Specification |
1/8 |
5/32 |
3/16 |
1/4 |
5/16 |
3/8 |
1/2 |
5/8 |
3/4 |
1 |
1-1/4 |
1-1/2 |
1-3/4 |
2 |
|
|
PP |
40 |
32 |
32 |
24 |
20 |
18 |
16 |
13 |
11 |
10 |
9 |
7 |
7 |
6 |
|
|
d |
Nominal diameter |
4# |
6# |
8# |
10# |
1/4 |
5/16 |
3/8 |
1/2 |
5/8 |
3/4 |
7/8 |
1-1/8 |
1-1/4 |
1-1/2 |
|
Nominal diameter |
0.1120 |
0.1380 |
0.1640 |
0.1900 |
0.2500 |
0.3125 |
0.3750 |
0.5000 |
0.6250 |
0.7500 |
0.8750 |
1.1250 |
1.2500 |
1.5000 |
|
|
ds |
Max. |
0.123 |
0.154 |
0.185 |
0.248 |
0.3105 |
0.373 |
0.498 |
0.623 |
0.748 |
0.998 |
1.248 |
1.498 |
1.748 |
1.998 |
|
Min. |
0.121 |
0.152 |
0.183 |
0.246 |
0.3085 |
0.371 |
0.496 |
0.621 |
0.746 |
0.996 |
1.246 |
1.496 |
1.746 |
1.996 |
|
|
dk |
Max. |
0.25 |
0.281 |
0.312 |
0.375 |
0.438 |
0.562 |
0.75 |
0.875 |
1 |
1.312 |
1.75 |
2.125 |
2.375 |
2.75 |
|
Min. |
0.235 |
0.266 |
0.296 |
0.357 |
0.419 |
0.543 |
0.729 |
0.853 |
0.977 |
1.287 |
1.723 |
2.095 |
2.345 |
2.72 |
|
|
k |
Max. |
0.125 |
0.125 |
0.156 |
0.188 |
0.219 |
0.25 |
0.312 |
0.375 |
0.5 |
0.625 |
0.75 |
1 |
1.125 |
1.25 |
|
Min. |
0.115 |
0.115 |
0.146 |
0.177 |
0.209 |
0.24 |
0.302 |
0.365 |
0.49 |
0.61 |
0.735 |
0.98 |
1.105 |
1.23 |
|
|
s |
公称 |
0.078 |
0.094 |
0.094 |
0.125 |
0.156 |
0.188 |
0.25 |
0.312 |
0.375 |
0.5 |
0.625 |
0.875 |
1 |
1.25 |
|
t |
Min. |
0.067 |
0.067 |
0.079 |
0.094 |
0.117 |
0.141 |
0.188 |
0.234 |
0.281 |
0.375 |
0.469 |
0.656 |
0.75 |
0.937 |
|
b |
Thread length |
0.157 |
0.187 |
0.189 |
0.375 |
0.438 |
0.5 |
0.625 |
0.75 |
0.875 |
1 |
1.125 |
1.5 |
1.75 |
2 |
|
c |
Max. |
0.008 |
0.008 |
0.012 |
0.020 |
0.026 |
0.031 |
0.040 |
0.050 |
0.069 |
0.083 |
0.102 |
0.138 |
0.157 |
0.176 |
|
ds1 |
Min. |
0.108 |
0.140 |
0.154 |
0.227 |
0.289 |
0.352 |
0.477 |
0.602 |
0.727 |
0.977 |
1.227 |
1.478 |
1.728 |
1.978 |
|
ds2 |
Max. |
0.076 |
0.100 |
0.120 |
0.142 |
0.193 |
0.249 |
0.304 |
0.414 |
0.521 |
0.638 |
0.750 |
0.964 |
1.089 |
1.307 |
|
Min. |
0.069 |
0.093 |
0.112 |
0.133 |
0.182 |
0.237 |
0.291 |
0.397 |
0.502 |
0.616 |
0.726 |
0.934 |
1.059 |
1.277 |
|
|
L1 |
Max. |
0.040 |
0.040 |
0.040 |
0.093 |
0.093 |
0.093 |
0.093 |
0.093 |
0.093 |
0.125 |
0.125 |
0.125 |
0.125 |
0.125 |
|
L2 |
Max. |
0.078 |
0.063 |
0.069 |
0.083 |
0.100 |
0.111 |
0.125 |
0.154 |
0.182 |
0.200 |
0.222 |
0.286 |
0.286 |
0.333 |
|
r1 |
Min. |
0.006 |
0.007 |
0.008 |
0.009 |
0.012 |
0.015 |
0.020 |
0.024 |
0.030 |
0.040 |
0.050 |
0.060 |
0.070 |
0.080 |
|
r2 |
Max. |
0.016 |
0.018 |
0.018 |
0.023 |
0.028 |
0.031 |
0.035 |
0.042 |
0.051 |
0.055 |
0.062 |
0.072 |
0.072 |
0.102 |
|
Min. |
0.010 |
0.012 |
0.012 |
0.017 |
0.022 |
0.025 |
0.029 |
0.036 |
0.045 |
0.049 |
0.056 |
0.066 |
0.066 |
0.096 |
|
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