Related Resources: hardware

Wrench Openings Table

ANSI Hardware Design Guide
Metric Hardware Specification Charts and Tables

Wrench Openings Table for Hex and Square Nuts per. ASME B18.2.2

Dimensional data may also be used to define 3D Printing Model nut capture geometry width.

Wrench openings

Basic
Size
of
Wrench,
W
Maximum
Nut
Across
Flats
Note (1)
Allowance
Between
Nut
Flats
and
Wrench
Jaws
Note (2)
Wrench Openings
Tolerance
Min.
Note(2)
Max.
5⁄32
0.156
0.002
0.158
0.005
0.163
3⁄16
0.188
0.002
0.190
0.005
0.195
1⁄4
0.250
0.002
0.252
0.005
0.257
5⁄16
0.312
0.003
0.315
0.006
0.321
11⁄32
0.344
0.003
0.347
0.006
0.353
3⁄8
0.375
0.003
0.378
0.006
0.384
7⁄16
0.438
0.003
0.440
0.006
0.446
1⁄2
0.500
0.004
0.504
0.006
0.510
9⁄16
0.562
0.004
0.566
0.007
0.573
5⁄8
0.625
0.004
0.629
0.007
0.636
11⁄16
0.688
0.004
0.692
0.007
0.699
3⁄4
0.750
0.005
0.755
0.008
0.763
13⁄16
0.813
0.005
0.818
0.008
0.826
7⁄8
0.875
0.005
0.880
0.008
0.888
15⁄16
0.938
0.006
0.944
0.009
0.953
1
1.000
0.006
1.006
0.009
1.015
1-1⁄16
1.063
0.006
1.068
0.009
1.077
1-1⁄8
1.125
0.007
1.132
0.010
1.142
1-1⁄4
1.250
0.007
1.257
0.010
1.267
1-5⁄16
1.313
0.008
1.320
0.011
1.331
1-7⁄16
1.438
0.008
1.446
0.011
1.457
1-1⁄2
1.500
0.008
1.508
0.012
1.520
1-5⁄8
1.625
0.009
1.634
0.012
1.646
1-11⁄16
1.688
0.009
1.696
0.012
1.708
1-13⁄16
1.813
0.010
1.822
0.013
1.835
1-7⁄8
1.875
0.010
1.885
0.013
1.898
2
2.000
0.011
2.011
0.014
2.025
2-1⁄16
2.063
0.011
2.074
0.014
2.088
2-3⁄16
2.188
0.012
2.200
0.015
2.215
2-1⁄4
2.250
0.012
2.262
0.015
2.277
2-3⁄8
2.375
0.013
2.388
0.016
2.404
2-9⁄16
2.563
0.014
2.576
0.017
2.593
2-3⁄4
2.750
0.014
2.766
0.017
2.783
2-15⁄16
2.938
0.016
2.954
0.019
2.973
3-1⁄8
3.125
0.017
3.142
0.020
3.162
3-1⁄2
3.500
0.019
3.518
0.022
3.540
3-7⁄8
3.875
0.020
3.895
0.023
3.918
4-1⁄4
4.250
0.022
4.272
0.025
4.297
4-5⁄8
4.625
0.024
4.649
0.027
4.676
5
5.000
0.026
5.026
0.029
5.055
5-3⁄8
5.375
0.028
5.403
0.031
5.434
5-3⁄4
5.750
0.030
5.780
0.033
5.813
6-1⁄8
6.125
0.032
6.157
0.035
6.192

 

Basic
Size
of
Wrench,
W
Nominal Nut Sizes
Machine
Screw
Nuts
Square
Nuts
Hex Flat,
HexFlatJam,
Hex,Hex
Jam,
Hex Slotted,
Hex Thick,
Hex Thick Slotted,
Heavy Hex Slotted

Heavy Square,
Heavy Hex Flat,
Heavy Hex Flat
Jam,
Heavy Hex,
Heavy Hex Jam
5⁄32
#0, #1
...
...
...
3⁄16
#2, #3
...
...
...
1⁄4
#4
...
...
...
5⁄16
#5, #6
...
...
...
11⁄32
#8
...
...
...
3⁄8
#10
...
...
...
7⁄16
#12, 1⁄4
1⁄4
1⁄4
...
1⁄2
...
...
5⁄16
1⁄4
9⁄16
5⁄16
5⁄16
3⁄8
5⁄16
5⁄8
3⁄8
3⁄8
...
...
11⁄16
...
...
7⁄16
3⁄8
3⁄4
...
7⁄16
1⁄2
7⁄16
13⁄16
...
1⁄2
...
...
7⁄8
...
...
9⁄16
1⁄2
15⁄16
...
...
5⁄8
9⁄16
1
...
5⁄8
...
...
1-1⁄16
...
...
...
5⁄8
1-1⁄8
...
3⁄4
3⁄4
...
1-1⁄4
...
...
...
3⁄4
1-5⁄16
...
7⁄8
7⁄8
...
1-7⁄16
...
...
...
7⁄8
1-1⁄2
...
1
1
...
1-5⁄8
...
...
...
1
1-11⁄16
...
11⁄8
1-1⁄8
...
1-13⁄16
...
...
...
1-1⁄8
1-7⁄8
...
11⁄4
1-1⁄4
...
2
...
...
...
1-1⁄4
2-1⁄16
...
13⁄8
1-3⁄8
...
2-3⁄16
...
...
...
1-3⁄8
2-1⁄4
...
11⁄2
1-1⁄2
...
2-3⁄8
...
...
...
1-1⁄2
2-9⁄16
...
...
...
1-5⁄8
2-3⁄4
...
...
...
1-3⁄4
2-15⁄16
...
...
...
1-7⁄8
3-1⁄8
...
...
...
2
3-1⁄2
...
...
...
2-1⁄4
3-7⁄8
...
...
...
2-1⁄2
4-1⁄4
...
...
...
2-3⁄4
4-5⁄8
...
...
...
3
5
...
...
...
3-1⁄4
5-3⁄8
...
...
...
3-1⁄2
5-3⁄4
...
...
...
3-3⁄4
6-1⁄8
...
...
...
4

(1) Wrenches are normally marked with “Basic Wrench Size,” which corresponds to the basic (maximum, in most cases) width across flats dimension of the respective nut.
(2) Allowance (minimum clearance) between maximum width across flats of the nut and jaws of wrench equals (0.005W + 0.001). Tolerance on wrench opening equals plus (0.005W + 0.004 from minimum), where W p nominal size of wrench.

Related:

Link to this Webpage:

Copy Text to clipboard

Spider Optimizer

© Copyright 2000 - 2024, by Engineers Edge, LLC
www.engineersedge.com
All rights reserved
Disclaimer | Feedback
Advertising | Contact