Machinery's Handbook, 31st Edition
Metric Self-Threading Screws 1851 Table 2. Recommended Nominal Screw Lengths for Metric Tapping Screws ANSI/ASME B18.6.5M-2000 (Withdrawn)
Nominal Screw Size for Types AB, B, BF, and BT
2.2
-
2.9
3.5
4.2
4.8
5.5
6.3
8
9.5
Nominal Screw Length
Nominal Screw Size for Types D, F, and T
2
2.5
3
3.5
4
5
-
6
8
10
4 5 6 8
PH PH PH PH
A A A A
A A A A A
PH
A A A A
PH PH
10 13 16 20 25 30 35 40 45 50 55 60
A A A A A
A A A A A
PH
A A A A A A
A A A A A A A
PH
A A A A A A
PH
A A A A A A A
PH
A A A A A A A
A Table 3. ANSI Standard Thread and Point Dimensions for Types AB and B Metric Thread Forming Tapping Screws ANSI/ASME B18.6.5M-2000 (Withdrawn)
D 1
D 2
D 3
Y
Z
L
Min. Practical Nominal Screw Length d Type AB Type B
Basic Screw Diame ter
Point Taper Length Type B c
Point Length Factor TypeAB
Basic Thread Pitch
Thread Major Diameter
Thread Minor Diameter
Nominal Screw Size and Thread Pitch a
Point Diameter b
Ref. e
Ref. e Max. Min. Max. Min. Max. Min. Max. Min.
Ref. f
2.0 2.6 3.2 3.7 4.3 5.0 6.0 7.5
4 6 4 5 6 7 5 7 7 9 6 8 8 10 7 10 9 12 8 11 11 14 9 12 12 16 10 13 16 20 12 17
2.2 × 0.8 2.184 0.79 2.24 2.10 1.63 1.52 1.47 1.37 1.6 1.2 2.845 1.06 2.90 2.76 2.18 2.08 2.01 1.88 2.1 1.6 3.5 × 1.3 3.505 1.27 3.53 3.35 2.64 2.51 2.41 2.26 2.5 1.9 4.2 × 1.4 4.166 1.41 4.22 4.04 3.10 2.95 2.84 2.69 2.8 2.1 2.9 × 1 4.8 × 1.6 4.826 1.59 4.80 4.62 3.58 3.43 3.30 3.12 3.2 2.4 5.5 × 1.8 5.486 1.81 5.46 5.28 4.17 3.99 3.86 3.68 3.6 2.7 6.3 × 1.8 6.350 1.81 6.25 6.03 4.88 4.70 4.55 4.34 3.6 2.7 8 × 2.1 7.938 2.12 8.00 7.78 6.20 5.99 5.84 5.64 4.2 3.2 9.5 × 2.1 9.525 2.12 9.65 9.43 7.85 7.59 7.44 7.24 4.2 3.2
8.0 19 24 14 19 a The body diameter (unthreaded portion) is not less than the minimum minor diameter nor greater than the maximum major diameter of the thread. b The tabulated values shall apply to screw blanks prior to roll threading. c The tabulated maximum limits are equal to approximately two times the thread pitch. d Lengths shown are theoretical minimums and are intended to assist the user in the selection of appropriate short screw lengths. Refer to Table 2 for recommended diameter-length combinations. e Basic screw diameter and basic thread pitch shall be used for calculation purposes wherever these factors appear in formulations for dimensions. f The minimum effective grip length on Type AB tapping screws shall be determined by subtracting the point length factor from the minimum screw length. All dimensions are in millimeters. See Table 1 for thread diagrams.
7 Pan, hex, and hex flange heads. 8 Flat and oval countersunk heads.
Copyright 2020, Industrial Press, Inc.
ebooks.industrialpress.com
Made with FlippingBook - Share PDF online