Threads and Threading - Sportpilot.info
Threads and Threading - Sportpilot.info
Threads and Threading - Sportpilot.info
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Nominal<br />
Sizes<br />
(All Classes)<br />
Table 9. American National St<strong>and</strong>ard Centralizing Acme Single-Start Screw Thread Data ASME/ANSI B1.5-1988<br />
Identification Diameters Thread Data<br />
<strong>Threads</strong><br />
per<br />
Inch, a<br />
n<br />
Centralizing, Classes 2C, 3C, <strong>and</strong> 4C<br />
Basic Major<br />
Diameter,<br />
D<br />
Pitch<br />
Diameter,<br />
D 2 = (D − h)<br />
Minor<br />
Diameter,<br />
D 1 = (D − 2h)<br />
Pitch,<br />
P<br />
Thickness at<br />
Pitch Line,<br />
t = P/2<br />
Basic<br />
Height of<br />
Thread,<br />
h = P/2<br />
Basic Width<br />
of Flat,<br />
F = 0.3707P<br />
Lead Angle λ at Basic Pitch Diameter a<br />
Centralizing Classes 2C, 3C, <strong>and</strong> 4C,<br />
Deg Min<br />
1 ⁄4 16 0.2500 0.2188 0.1875 0.06250 0.03125 0.03125 0.0232 5 12<br />
5 ⁄16 14 0.3125 0.2768 0.2411 0.07143 0.03571 0.03571 0.0265 4 42<br />
3 ⁄8 12 0.3750 0.3333 0.2917 0.08333 0.04167 0.04167 0.0309 4 33<br />
7 ⁄16 12 0.4375 0.3958 0.3542 0.08333 0.04167 0.04167 0.0309 3 50<br />
1 ⁄2 10 0.5000 0.4500 0.4000 0.10000 0.05000 0.05000 0.0371 4 3<br />
5 ⁄8 8 0.6250 0.5625 0.5000 0.12500 0.06250 0.06250 0.0463 4 3<br />
3 ⁄4 6 0.7500 0.6667 0.5833 0.16667 0.08333 0.08333 0.0618 4 33<br />
7 ⁄8 6 0.8750 0.7917 0.7083 0.16667 0.08333 0.08333 0.0618 3 50<br />
1 5 1.0000 0.9000 0.8000 0.20000 0.10000 0.10000 0.0741 4 3<br />
1 1 ⁄ 8 5 1.1250 1.0250 0.9250 0.20000 0.10000 0.10000 0.0741 3 33<br />
1 1 ⁄ 4 5 1.2500 1.1500 1.0500 0.20000 0.10000 0.10000 0.0741 3 10<br />
1 3 ⁄ 8 4 1.3750 1.2500 1.1250 0.25000 0.12500 0.12500 0.0927 3 39<br />
1 1 ⁄ 2 4 1.5000 1.3750 1.2500 0.25000 0.12500 0.12500 0.0927 3 19<br />
1 3 ⁄ 4 4 1.7500 1.6250 1.5000 0.25000 0.12500 0.12500 0.0927 2 48<br />
2 4 2.0000 1.8750 1.7500 0.25000 0.12500 0.12500 0.0927 2 26<br />
2 1 ⁄ 4 3 2.2500 2.0833 1.9167 0.33333 0.16667 0.16667 0.1236 2 55<br />
2 1 ⁄ 2 3 2.5000 2.3333 2.1667 0.33333 0.16667 0.16667 0.1236 2 36<br />
2 3 ⁄ 4 3 2.7500 2.5833 2.4167 0.33333 0.16667 0.16667 0.1236 2 21<br />
3 2 3.0000 2.7500 2.5000 0.50000 0.25000 0.25000 0.1853 3 19<br />
3 1 ⁄ 2 2 3.5000 3.2500 3.0000 0.50000 0.25000 0.25000 0.1853 2 48<br />
4 2 4.0000 3.7500 3.5000 0.50000 0.25000 0.25000 0.1853 2 26<br />
4 1 ⁄ 2 2 4.5000 4.2500 4.0000 0.50000 0.25000 0.25000 0.1853 2 9<br />
5 2 5.0000 4.7500 4.5000 0.50000 0.25000 0.25000 0.1853 1 55<br />
a All other dimensions are given in inches.<br />
Machinery's H<strong>and</strong>book 27th Edition<br />
Copyright 2004, Industrial Press, Inc., New York, NY<br />
1840<br />
CENTRALIZING ACME SCREW THREADS