Page 388 - THREADING CATALOG

USER GUIDE
TAPS UNIFIED Coarse Thread

Nominal Dimensions According to ANSI B1.1
Tap flank diameter production tolerances for ISO 2B Coarse Pitch Threads Dimensions in mm
Nut threads limit dimensions - nut threads ANSI B1.1, 2B-3B
1/8·H H = 0.86603P
nut thread
5
H1 = H = 0.54127P
8
1/2·H H1 h3 h3 = 17 H = 0.61343P
H 60° 24 3
4
60° d2 = D2 = d- H = d-0.64952P
1/2·H screw
1/4·H 1/6·H d3 = d-2h3 = d-1.22687P
r H
r = = 0.14434P
6
DD2 D1 P d3 d2 d
Pitch diameter
Flank Minor diameter Tap tolerance 2B Pitch diameter Nut tolerance
External Dia. max.
Nominal T.P.I Dia. Pitch P Dia. d=D d2=D2 Nut D1 Screw h3 Min. Max. 2B/3B max. 2B max. 3B
UNC#1 - 64 0.397 1.854 1.598 1.425 1.367 1.610 1.623 1.598 1.664 1.646
UNC# 2 - 64 0.454 2.184 1.890 1.694 1.628 1.902 1.915 1.890 1.961 1.943
UNC#3 - 48 0.529 2.515 2.172 1.941 1.864 2.184 2.197 2.172 2.248 2.228
UNC# 4 - 40 0.635 2.845 2.433 2.156 2.065 2.446 2.459 2.433 2.517 2.494
UNC# 5 - 40 0.635 3.175 2.764 2.487 2.395 2.776 2.789 2.764 2.847 2.827
UNC# 6 - 32 0.794 3.505 2.990 2.647 2.532 3.105 3.028 2.990 3.084 3.058
UNC# 8 - 32 0.794 4.166 3.650 3.307 3.193 3.675 3.688 3.650 3.746 3.721
UNC# 10 - 24 1.058 4.826 4.138 3.680 3.528 4.163 4.176 4.138 4.247 4.219
UNC# 12 - 24 1.058 5.486 4.798 4.341 4.188 4.823 4.836 4.798 4.910 4.882
UNC 1/4" - 20 1.270 6.350 5.524 4.976 4.793 5.575 5.588 5.524 5.646 5.616
UNC 5/16" - 18 1.411 7.938 7.021 6.411 6.205 7.071 7.084 7.021 7.155 7.120
UNC 3/8" - 16 1.588 9.525 8.494 7.805 7.577 8.545 8.557 8.494 8.639 8.603
UNC 7/16" - 14 1.814 11.112 9.934 9.149 8.887 9.985 9.997 9.934 10.089 10.051
UNC 1/2" - 13 1.954 12.700 11.430 10.584 10.302 11.481 11.494 11.430 11.595 11.552
UNC 9/16" - 12 2.117 14.288 12.913 11.996 11.692 12.964 12.977 12.913 13.086 13.043
UNC 5/8" - 11 2.309 15.875 14.376 13.376 13.043 14.427 14.440 14.376 14.559 14.514
UNC 3/4" - 10 2.540 19.050 17.399 16.229 15.933 17.450 17.463 17.399 17.595 17.544
UNC 7/8" - 9 2.822 22.225 20.391 19.169 18.763 20.455 20.467 20.391 20.599 20.546
UNC 1" - 8 3.175 25.400 23.338 21.963 21.504 23.401 23.414 23.338 23.561 23.505
UNC 1 1/8" - 7 3.629 28.575 26.218 24.648 24.122 26.294 26.319 26.218 26.457 26.398
UNC 1 1/4" - 7 3.629 31.750 29.393 27.823 27.297 29.469 29.494 29.393 29.637 29.576
UNC 1 3/8" - 6 4.233 34.925 32.174 30.343 29.731 32.250 32.276 32.174 32.438 32.372
UNC 1 1/2" - 6 4.233 38.100 35.349 33.518 32.906 35.425 35.451 35.349 35.616 35.550
UNC 1 3/4" - 5 5.080 44.450 41.151 38.951 38.217 41.241 41.266 41.151 41.445 41.372
UNC 2" - 4 1/2 5.644 50.800 47.135 44.689 43.876 47.235 47.260 47.135 47.450 47.371
UNC 2 1/4" - 4 1/2 5.644 57.150 53.485 51.039 50.226 53.485 53.805 53.726
UNC 2 1/2" - 4 6.350 63.500 59.375 56.627 55.710 59.375 59.718 59.632
UNC 2 3/4" - 4 6.350 69.850 65.725 62.977 62.060 65.725 66.073 65.987
UNC 3" - 4 6.350 76.200 72.075 69.327 68.410 72.075 72.428 72.339
UNC 3 1/4" - 4 6.350 82.550 78.425 75.677 74.760 78.425 78.783 78.694
UNC 3 1/2" - 4 6.350 88.900 84.775 82.027 81.110 84.775 85.183 85.049
UNC 3 3/4" - 4 6.350 95.250 91.125 88.377 87.460 91.125 91.493 91.402
UNC 4" - 4 6.350 101.600 97.475 94.727 93.810 97.475 97.848 97.757

ISCAR
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