Machinery's Handbook, 31st Edition
Acme and Square-Threaded Taps 1011 Table 28. Proportions of Acme and Square-Threaded Taps Made in Sets
R –0.010 "
B
A
C
L
R = root diameter of thread T = double depth of full thread
D = full diameter of tap
No. of Taps in Set
Order of Tap in Set
Types of Tap
A
B
C
1st 2d 1st 2d 3d 1st 2d 3d 4th 1st 2d 3d 4th 5th 1st 2d 1st 2d 3d 1st 2d 3d 4th 1st 2d 3d 4th 5th
R + 0.65 T
R + 0.010
8 L to 4 L to 8 L to 6 L to 4 L to
1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄
1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄
6 L 3 L 6 L 4 L 3 L
2
A on 1st tap - 0.005
D
R + 0.45 T R + 0.80 T R + 0.40 T R + 0.70 T R + 0.90 T D R + 0.37 T R + 0.63 T R + 0.82 T R + 0.94 T D
R + 0.010
3
A on 1st tap - 0.005 A on 2d tap - 0.005 A on 1st tap - 0.005 A on 2d tap - 0.005 A on 3d tap - 0.005 R + 0.010 A on 1st tap - 0.005 A on 2d tap - 0.005 A on 3d tap - 0.005 A on 4th tap - 0.005 R + 0.010
8 L 6 L 5 L 8 L 6 L 5 L
Acme Thread Taps
4
4 L to
1 ⁄
3 L
5
5 L to 4 L to 8 L to 4 L to 8 L to 6 L to 4 L to
1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄ 1 ⁄
4 L 3 L 6 L 3 L 6 L 4 L 3 L
D
R + 0.67 T
R
2
A on 1st tap - 0.005
D
R + 0.41 T R + 0.080 T R + 0.32 T R + 0.62 T R + 0.90 T D R + 0.26 T R + 0.50 T R + 0.72 T R + 0.92 T D
R
3
A on 1st tap - 0.005 A on 2d tap - 0.005 A on 1st tap - 0.005 A on 2d tap - 0.005 A on 3d tap - 0.005 R A on 1st tap - 0.005 A on 2d tap - 0.005 A on 3d tap - 0.005 A on 4th tap - 0.005 R
8 L 6 L 5 L 8 L 6 L 5 L
Square- Threaded Taps
4
4 L to
1 ⁄
3 L
5
5 L to 4 L to
1 ⁄ 1 ⁄
4 L 3 L
D
2 -10 Acme 2G, pitch = 1 ⁄ 10 = 0.1
Example: 1 ⁄
minimum diameter = 0.5 - 0.1 = 0.4
Copyright 2020, Industrial Press, Inc.
ebooks.industrialpress.com
Made with FlippingBook - Share PDF online