Threads and Threading - Sportpilot.info

Threads per
Inch Pitch
Depth
of Sharp
V-Thread
All dimensions are in inches.
Depth of
Int. Thd.
and UN
Ext. Thd. a
a Also depth of thread engagement.
b Design profile.
c Also basic flat at external UN thread root.
Table 1. American Standard Unified Inch Screw Thread Form Data
Depth of
UNR
Ext. Thd.
Machinery's Handbook 27th Edition
Truncation
of Ext. Thd.
Root
Truncation
of UNR
Ext. Thd.
Root b
Truncation
of
Ext. Thd.
Crest
Truncation
of
Int. Thd.
Root
Truncation
of
Int. Thd.
Crest
Flat at Ext.
Thd. Crest
and Int. Thd.
Root
Basic
Flat at
Int. Thd.
Crest c
Maximum
Ext. Thd.
Root
Radius
Addendum
of
Ext. Thd.
n P 0.86603P 0.54127P 0.59539P 0.21651P 0.16238P 0.10825P 0.10825P 0.2165P 0.125P 0.25P 0.14434P 0.32476P
80 0.01250 0.01083 0.00677 0.00744 0.00271 0.00203 0.00135 0.00135 0.00271 0.00156 0.00312 0.00180 0.00406
72 0.01389 0.01203 0.00752 0.00827 0.00301 0.00226 0.00150 0.00150 0.00301 0.00174 0.00347 0.00200 0.00451
64 0.01563 0.01353 0.00846 0.00930 0.00338 0.00254 0.00169 0.00169 0.00338 0.00195 0.00391 0.00226 0.00507
56 0.01786 0.01546 0.00967 0.01063 0.00387 0.00290 0.00193 0.00193 0.00387 0.00223 0.00446 0.00258 0.00580
48 0.02083 0.01804 0.01128 0.01240 0.00451 0.00338 0.00226 0.00226 0.00451 0.00260 0.00521 0.00301 0.00677
44 0.02273 0.01968 0.01230 0.01353 0.00492 0.00369 0.00246 0.00246 0.00492 0.00284 0.00568 0.00328 0.00738
40 0.02500 0.02165 0.01353 0.01488 0.00541 0.00406 0.00271 0.00271 0.00541 0.00312 0.00625 0.00361 0.00812
36 0.02778 0.02406 0.01504 0.01654 0.00601 0.00451 0.00301 0.00301 0.00601 0.00347 0.00694 0.00401 0.00902
32 0.03125 0.02706 0.01691 0.01861 0.00677 0.00507 0.00338 0.00338 0.00677 0.00391 0.00781 0.00451 0.01015
28 0.03571 0.03093 0.01933 0.02126 0.00773 0.00580 0.00387 0.00387 0.00773 0.00446 0.00893 0.00515 0.01160
27 0.03704 0.03208 0.02005 0.02205 0.00802 0.00601 0.00401 0.00401 0.00802 0.00463 0.00926 0.00535 0.01203
24 0.04167 0.03608 0.02255 0.02481 0.00902 0.00677 0.00451 0.00451 0.00902 0.00521 0.01042 0.00601 0.01353
20 0.05000 0.04330 0.02706 0.02977 0.01083 0.00812 0.00541 0.00541 0.01083 0.00625 0.01250 0.00722 0.01624
18 0.05556 0.04811 0.03007 0.03308 0.01203 0.00902 0.00601 0.00601 0.01203 0.00694 0.01389 0.00802 0.01804
16 0.06250 0.05413 0.03383 0.03721 0.01353 0.01015 0.00677 0.00677 0.01353 0.00781 0.01562 0.00902 0.02030
14 0.07143 0.06186 0.03866 0.04253 0.01546 0.01160 0.00773 0.00773 0.01546 0.00893 0.01786 0.01031 0.02320
13 0.07692 0.06662 0.04164 0.04580 0.01655 0.01249 0.00833 0.00833 0.01665 0.00962 0.01923 0.01110 0.02498
12 0.08333 0.07217 0.04511 0.04962 0.01804 0.01353 0.00902 0.00902 0.01804 0.01042 0.02083 0.01203 0.02706
11 1 ⁄ 2 0.08696 0.07531 0.04707 0.05177 0.01883 0.01412 0.00941 0.00941 0.01883 0.01087 0.02174 0.01255 0.02824
11 0.09091 0.07873 0.04921 0.05413 0.01968 0.01476 0.00984 0.00984 0.01968 0.01136 0.02273 0.01312 0.02952
10 0.10000 0.08660 0.05413 0.05954 0.02165 0.01624 0.01083 0.01083 0.02165 0.01250 0.02500 0.01443 0.03248
9 0.11111 0.09623 0.06014 0.06615 0.02406 0.01804 0.01203 0.01203 0.02406 0.01389 0.02778 0.01604 0.03608
8 0.12500 0.10825 0.06766 0.07442 0.02706 0.02030 0.01353 0.01353 0.02706 0.01562 0.03125 0.01804 0.04059
7 0.14286 0.12372 0.07732 0.08506 0.03093 0.02320 0.01546 0.01546 0.03093 0.01786 0.03571 0.02062 0.04639
6 0.16667 0.14434 0.09021 0.09923 0.03608 0.02706 0.01804 0.01804 0.03608 0.02083 0.04167 0.02406 0.05413
5 0.20000 0.17321 0.10825 0.11908 0.04330 0.03248 0.02165 0.02165 0.04330 0.02500 0.05000 0.02887 0.06495
4 1 ⁄ 2 0.22222 0.19245 0.12028 0.13231 0.04811 0.03608 0.02406 0.02406 0.04811 0.02778 0.05556 0.03208 0.07217
4 0.25000 0.21651 0.13532 0.14885 0.05413 0.04059 0.02706 0.02706 0.05413 0.03125 0.06250 0.03608 0.08119
Copyright 2004, Industrial Press, Inc., New York, NY
1734
UNIFIED SCREW THREADS