Plow Bolts: Dimensions & Specifications

 Number 7 Plow Bolt Dimensions

Dimensions of No. 7 Head Plow Bolts (Round, Countersunk, Reverse Key)

Nominal or Basic Bolt Diameter, D

Diameter of Full-Size Body, E

Diameter of Head, A

Maximum Feed Thickness, F

Head Height, S

Key Length, G
Max. Min. Max. Min. Sharp ABS Min. with Flat Max. Min. Min. Max.

Regular Head
5/16 0.3125 0.312 0.299 0.592 0.578 0.546 0.040 0.233 0.208 0.185 0.200
3/8 0.3750 0.375 0.360 0.661 0.640 0.603 0.050 0.239 0.208 0.187 .0202
7/16 0.4375 0.438 0.421 0.776 0.749 0.09 0.058 0.282 0.246 0.227 0.242
1/2 0.5000 0.500 0.483 0.892 0.859 0.814 0.068 0.328 0.286 0.267 0.282
9/16

[Note(1)]

 0.5625

[Note(1)]

 0.592 0.544 1.021 0.984 0.938 0.072 0.383 0.338 0.321 0.336
5/8 0.6250 0.657 0.606 1.121 1.078 1.028 0.080 0.414 0.364 0.348 0.363
3/4 0.7500 0.782 0.729 1.277 1.234 1.184 0.080 0.440 0.390 0.375 0.390

Repair Head [Note (2)]
5/16 0.3125 0.312  0.299  0.554  0.546  0.517 0.032 0.201 0.181 0.158 0.173
3/8 0.3750 0.375 0.360 0.623 0.609 0.577 0.040 0.207 0.182 0.158 0.173
7/16 0.4375 0.438 0.421 0.738 0.718 0.682 0.048 0.250 0.220 0.199 0.214
1/2 0.5000 0.500 0.483 0.853 0.828 0.789 0.056 0.295 0.260 0.293 0.254
9/16

[Note(1)]

 0.5625

[Note(1)]

 0.592 0.544 0.984 0.953 0.910 0.064 0.352 0.312 0.293 0.308
5/8 0.6250 0.657 0.606 1.077 1.046 1.003 0.064 0.378 0.338 0.321 0.336
3/4 0.7500 0.782 0.729 1.234 1.203 1.160 0.064 0.404 0.364 0.347 0.362

(1) This size is not recommended

(2) The letter "R" should be shown on the top of the repair head to distinguish it from the regular head bolt.

 

Number 3 Head Plow Bolt Dimensions

Dimensions of No. 3 Head Plow Bolts (Round, Countersunk, Square Neck)

 

Nominal or Basic Bolt Diameter, D

 

Diameter of Full-Size Body, E

 

Diameter of  Head, A

 

Maximum Feed Thickness, F

 

Depth of Square and Head, S

 

Minimum Square Corner Length, T

 

Width of Square, B

 

Minimum Across Corners, AC

 

Maximum Radius on Corners of Square, R

[Note (1)]

Max. Min. Max. Min. Sharp ABS Min.  Max. Min. Max. Min. (Basic)

Regular Head
5/16 0.3125 0.312 0.299 0.605 0.578 0.538 0.040 0.269 0.228 0.176 0.325 0.313 0.417 0.031
3/8 0.3750 0.375 0.360 0.708 0.671 0.64 0.050 0.312 0.262 0.206 0.387 0.375 0.491 0.047
7/16 0.4375 0.438 0.421 0.826 0.781 0.729 0.058 0.364 0.306 0.235 0.450 0.438 0.580 0.047
1/2 0.5000 0.500 0.483 0.945 0.890 0.831 0.068 0.417 0.349 0.235 0.515 0.500 0.668 0.047
9/16

[Note(2)]

 0.5625

[Note(2)]

 0.592 0.544 1.045 1.000 0.924 0.072 0.461 0.389 0.305 0.578 0.563 0.732 0.078
5/8 0.6250 0.657 0.606 1.147 1.094 1.013 0.080 0.506 0.426 0.330 0.640 0.625 0.819 0.078
3/4 0.7500 0.782 0.729 1.303 1.250 1.169 0.080 0.541 0.461 0.338 0.765 0.750 0.996 0.078
7/8 0.8750 0.938 0.853 1.512 1.469 1.344 0.100 0.626 0.526 0.384 0.906 0.875 1.160 0.094
1 1.0000 1.062 0.976 1.700 1.656 1.532 0.100 0.690 0.590 0.422 1.031 1.000 1.336 0.094

Repair Head [Note (3)]
5/16 0.3125 0.312 0.299 0.556 0.531 0.496 0.032 0.232 0.200 0.139 0.325 0.313 0.417 0.031
3/8 0.3750 0.375 0.360 0.659 0.624 0.584 0.040 0.272 0.232 0.166 0.387 0.375 0.491 0.047
7/16 0.4375 0.438 0.421 0.779 0.734 0.689 0.048 0.324 0.276 0.195 0.450 0.438 0.580 0.047
1/2 0.5000 0.500 0.483 0.898 0.843 0.793 0.056 0.375 0.319 0.223 0.515 0.500 0.668 0.047
9/16 0.5625 0.592 0.544 1.002 0.953 0.882 0.064 0.423 0.359 0.267 0.578 0.578 0.732 0.078
5/8 0.6250 0.627 0.606 1.096 1.047 0.976 0.064 0.458 0.394 0.282 0.640 0.640 0.819 0.078
3/4 0.7500 0.782 0.729 1.252 1.203 1.132 0.064 0.493 0.429 0.290 0.765 0.765 0.996 0.078
7/8 0.8750 0.938 0.853 1.465 1.422 1.309 0.080 0.573 0.493 0.331 0.906 0.906 1.160 0.094
1 1.0000 0.976 0.976 1.623 1.609 1.497 0.080 0.637 0.557 0.369 1.031 1.031 1.336 0.094

NOTES:

(1) If the method of Manufacture permits, it is recommended that the same radius be maintained on each of all four corners of the square.

(2) This size is not recommended

(3) The letter "R" should be shown on the top of the repair head to distinguish it from the regular head bolt.

 

Number 4 Repair Head Plow Bolt Dimensions

Dimensions of No. 4 Repair Head Plow Bolts (Square Head, Countersunk)

Nominal or Basic Bolt Diameter, D

Diameter of Full-Size Body, E

Width of Head, A

Maximum Feed Thickness, F
Max. Min. Min. (Basic) Min. Max.
5/16 0.3125 0.3312 0.299 33/64 0.482 0.531 0.040
3/8 0.3750 0.375 0.360 41/64 0.599 0.656 0.050
7/16 0.4375 0.438 0.421 45/64 0.653 0.718 0.060
1/2 0.5000 0.500 0.438 49/64 0.707 0.781 0.070
9/16 0.5625 0.592 0.544 57/64 0.824 0.922 0.080
5/8 0.6250 0.657 0.606 61/64 0.886 0.984 0.080
3/4 0.7500 0.782 0.729 1 5/64 1.011 1.109 0.080
7/8 0.8750 0.938 0.853 1 17/64 1.199 1.297 0.080
1 1.0000 1.062 0.976 1 29/64 1.386 1.484 0.080

 

Number 6 Repair Head Plow Bolt Dimensions

Dimensions of No. 6 Repair Head Plow Bolts (Round, Countersunk, Heavy Key)

Nominal or Basic Bolt Diameter, D

Diameter of Full-Size Body, E

Diameter of Head, A

Maximum Height of Head, H

Maximum Height of Head, H

Maximum Key Width, J
Max. Min. Max. Min.
3/8 0.3750 0.375 0.360 0.708 0.723 0.025 0.286 0.156
7/16 0.4375 0.438 0.421 0.770 0.785 0.030 0.339 0.172
1/2 0.5000 0.500 0.483 0.836 0.851 0.035 0.402 0.188

 

 Clipped Head Plow Bolt Dimensions

Clipped Head Plow Bolt

Nominal or Basic Bolt Diameter

Diameter of Head, A

Width Across Clipped Flats, B

Height of Head, H

Maximum Angle of Transition, P, deg
Max. Min. Max. Min. Max. Min.
3/8 0.3750 0.565 0.535 0.470 0.445 0.350 0.335 45
7/16 0.4375 0.605 0.595 0.540 0.530 0.391 0.359 45
1/2 0.5000 0.680 0.670 0.580 0.570 0.391 0.359 40

 

 Elliptical Head Plow Bolt Dimensions

Elliptical Head Plow Bolt

Nominal or Basic Bolt Diameter

Elongated Head Dimension, A

Narrow Head Dimension, C

Large Radius of Head, F, Ref

Small Radius of Head, G, Ref

Width of Square, B

Minimum Across Corners, AC

Depth of Square, S

Minimum Square Corner Length, T

Maximum Radius on Corners of Square, R
Max. Min. Max. Min. Max. Min. Max. Min.
3/8 0.3750 0.630 0.600 0.710 0.670 0.375 0.250 0.387 0.375 0.491 0.330 0.300 0.244 0.047
7/16 0.4375 0.733 0.703 0.820 0.780 0.438 0.312 0.451 0.437 0.580 0.420 0.380 0.309 0.047

 

 

Minimum Thread Lengths of Plow Bolts (2D + 0.25)

 

 Recommended Bolt Length, L

[Note (1)]

Nominal Bolt Diameter, D

5/16

0.3125

3/8

0.375

7/16

0.4375

1/2

0.500

9/16

0.5625

[Note (2)]

5/8

0.625

3/4

0.750

7/8

0.875

1

1.000
3/4 0.75 T to H T to H T to H T to H T to H T to H T to H T to H T to H
1 1.00 T to H T to H T to H T to H T to H T to H T to H T to H T to H
1 1/4 1.25 0.875 T to H T to H T to H T to H T to H T to H T to H T to H
1 1/2 1.50 0.875 1.000 T to H T to H T to H T to H T to H T to H T to H
1 3/4 1.75 0.875 1.000 1.125 1.250 T to H T to H T to H T to H T to H
2 2.00 0.875 1.000 1.125 1.250 1.375 T to H T to H T to H T to H
2 1/4 2.25 0.875 1.000 1.125 1.250 1.375 1.500 T to H T to H T to H
2 1/2 2.50 0.875 1.000 1.125 1.250 1.375 1.500 1.750 T to H T to H
2 3/4 2.75 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 T to H
3 3.00 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
3 1/4 3.25 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
3 1/2 3.50 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
3 3/4 3.75 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
4 4.00 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
4 1/4 4.25 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
4 1/2 4.50 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
4 3/4 4.75 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
5 5.00 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
5 1/4 5.25 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
5 1/2 5.50 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
5 3/4 5.75 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250
6 6.00 0.875 1.000 1.125 1.250 1.375 1.500 1.750 2.00 2.250

GENERAL NOTE:

T to H: threaded to head or square within 2 1/2 full threads

NOTES:

(1) Short lengths shown above the solid stepped line are not recommended

(2) This size is not recommended for regular head bolts

 

Tolerance on Length

Nominal Diam 

1/4 Through 3/8 

0.250 Through 0.375

Nominal Diam. 

7/16 and 1/2 

0.4375 and 0.500

Nominal Diam. 

9/16 Through 1 

0.5625 Through 1.000
±0.03 ±0.06 ±0.12

 

Plus Tolerance on Thread Length

Nominal Diameter, D

Tolerance Plus
5/16 0.3125 0.139
3/8 0.3750 0.156
7/16 0.4375 0.179
1/2 0.5000 0.192
9/16 0.5625 0.208
5/8 0.6250 0.227
3/4 0.7500 0.250
7/8 0.8750 0.278
1 1.0000 0.312

 

Frequently Asked Questions

Q: How to measure plow bolts?

A: For flat head plow bolts, the length is measured from the top of the head to the very end of the threaded bolt. For dome head plow bolts, you will measure the length from the largest diameter point of the head to the very end of the threaded bolt.

Q: What are plow bolts used for?

A: Plow bolts are commonly used in road graders, scoop shovels, and other heavy-duty industrial equipment where a flat, smooth surface is required.