B7

Alloy steel, AISI 4140/4142 quench & tempered

B8

Class 1 Stainless steel, AISI 304, carbide solution treated

B8M

Class 1 Stainless steel, AISI 316, carbide solution treated

B8

Class 2 Stainless steel, AISI 304, carbide solution treated, strain hardened

B8M

Class 2 Stainless steel, AISI 316, carbide solution treated, strain hardened

Grade

Size

Tensile ksi, min

Yield, ksi, min

Elong, %, min

RA % min

B7

Up to 2-1/2

125

105

16

50

2-5/8 - 4

115

95

16

50

4-1/8 - 7

100

75

18

50

B8 Class 1

All

75

30

30

50

B8M Class 1

All

75

30

30

50

B8 Class 2

Up to 3/4

125

100

12

35

7/8 - 1

115

80

15

35

1-1/8 - 1-1/4

105

65

20

35

1-3/8 - 1-1/2

100

50

28

45

B8M Class 2

Up to 3/4

110

95

15

45

7/8 - 1

100

80

20

45

1-1/8 - 1-1/4

95

65

25

45

1-3/8 - 1-1/2

90

50

30

45

Grade

Nuts

Washers

B7

A194 Grade 2H

F436

B8 Class 1

A194 Grade 8

SS304

B8M Class 1

A194 Grade 8M

SS316

B8 Class 2

A194 Grade 8, strain hardened

SS304

B8M Class 2

A194 Grade 8M, strain hardened

SS316

2

Carbon steel heavy hex nuts

2H

Quenched & tempered carbon steel heavy hex nuts

2HM

Quenched & tempered carbon steel heavy hex nuts

4

Quenched & tempered carbon-molybdenum heavy hex nuts

7

Quenched & tempered alloy steel heavy hex nuts

7M

Quenched & tempered alloy steel heavy hex nuts

8

Stainless AISI 304 heavy hex nuts

8M

Stainless AISI 316 heavy hex nuts

A

Headed bolts, threaded rods and bent bolts intended for general applications.

B

Heavy hex bolts and studs intended for flanged joints in piping systems with cast iron flanges.

C

Anchor bolts, either bent or straight, intended for structural anchorage purposes. The end of a grade C anchor bolt intended to project from the concrete will be painted green for identification purposes. Permanent marking is a supplemental requirement. *As of August 2007, grade C has been replaced by specification F1554 grade 36 . Northstar will continue to supply grade C, if required by the project.

Grade

Tensile, ksi

Yield, min, ksi

Elong %, min

A

60 min

--

18

B

60 - 100

--

18

C

58 - 80

36

23

Nuts

Washers

A307 Grades A & C

A307 Grade B

1/4 – 1-1/2

1-5/8 - 4

1/4 -4

A563A Hex

A563A Heavy Hex

F844

L7

Alloy steel, AISI 4140/4142 quench & tempered

L43

Alloy steel, AISI 4340 quench & tempered

B8

Class 1 Stainless steel, AISI 304, carbide solution treated

B8M

Class 1 Stainless steel, AISI 316, carbide solution treated

B8

Class 2 Stainless steel, AISI 304, carbide solution treated, strain hardened

B8M

Class 2 Stainless steel, AISI 316, carbide solution treated, strain hardened

Grade

Size

Tensile,
ksi, min

Yield,
ksi, min

Charpy Impact
20-ft-lbf
@ temp

Elong,
%, min

RA, %, min

L7

Up to 2 1 / 2

125

105

-150° F

16

50

L43

Up to 4

125

105

-150° F

16

50

B8
Class 1

All

75

30

N/A

30

50

B8M
Class 1

All

75

30

N/A

30

50

B8
Class 2

Up to 3 / 4

125

100

N/A

12

35

7 / 8 - 1

115

80

N/A

15

35

1 1 / 8 - 1 1 / 4

105

65

N/A

20

35

1 3 / 8 - 1 1 / 2

100

50

N/A

28

45

B8M
Class 2

Up to 3 / 4

110

95

N/A

15

45

7 / 8 - 1

100

80

N/A

20

45

1 1 / 8 - 1 1 / 4

95

65

N/A

25

45

1 3 / 8 - 1 1 / 2

90

50

N/A

30

45

Grade

Nuts

Washers

L7

A194 Grade 4 or 7

F436

L43

A194 Grade 4 or 7

F436

B8 Class 1

A194 Grade 8

SS304

B8M Class 1

A194 Grade 8M

SS316

B8 Class 2

A194 Grade 8 , strain hardened

SS304

B8M Class 2

A194 Grade 8M , strain hardened

SS316

TYPE 1

Medium carbon, carbon boron, or medium carbon alloy steel

TYPE 2

Withdrawn November 1991

TYPE 3

Weathering steel

T

Fully threaded per ASTM A325

M

Metric A325

SC

Slip critical connection

N

Bearing type connection with threads included in the shear plane

X

Bearing type connection with threads excluded from the shear plane

Size

Tensile, ksi

Yield, ksi

Elong %, min

RA %, min

1/2 – 1

120 min

92 min

14

35

1-1/8 – 1-1/2

105 min

81 min

14

35

Nuts

Washers

Type 1

Type 3

Type 1

Type 3

Plain

Galvanized

Plain

A563C, C3, D, DH, DH3

A563DH

A563C3, DH3

F463-1

F463-3

Note: Nuts conforming to A194-2H are a suitable substitute for use with A325 heavy hex structural bolts. The ASTM A563 Nut Compatibility Chart has a complete list of specifications.

A354 BC

Lower in strength than grade BD

A354 BD

A354 grade BD bolts are higher in strength than A354 grade BC and equal in strength to ASTM A490 bolts. Unlike ASTM A490 however, the A354 BD specification is unrestricted in its configuration. Since A490 bolts are heavy hex structural bolts and do not exceed 1-1/2" diameter, specification A354 BD should be considered for anchor bolts, threaded rods, other styles of headed bolts, and bolts larger than 1-1/2" diameter where similar mechanical properties are desired. A354 grade BD does not require a magnetic particle test as is required by the A490 specification.

Grade

Size

Tensile, ksi, min

Yield, ksi, min

Elong %, min

RA %, min

BC

1/4 – 2-1/2

125

109

16

50

2-5/8 – 4

115

99

16

45

BD

1/4 – 2-1/2

150

130

14

40

2-5/8 - 4

140

115

14

40

Nuts

Washers

Grade BC

Grade BD

Plain

Galvanized

Plain

A563C Heavy Hex

A563DH Heavy Hex

A563DH Heavy Hex

F436

* Nuts of other grades load stresses greater than the specified grade are suitable. Refer to ASTM A563 Nut Compatibility Chart for details.

TYPE 1

Plain carbon steel, carbon boron steel, alloy steel or alloy boron steel

TYPE 2

Withdrawn 2003

TYPE 3

Weathering steel

Size

Tensile, ksi

Yield, ksi

Elong %, min

RA %, min

1/4 – 1

120 min

92 min

14

35

1-1/8 – 1-1/2

105 min

81 min

14

35

1-5/8 - 3

90 min

58 min

14

35

Nuts

Washers

Plain

Galvanized

1/4 – 1-1/2

1-5/8 - 3

1/4 – 3

A563B Hex

A563A Heavy Hex

A563DH Heavy Hex

F436

Note: Nuts of other grades having proof load stresses greater than the specified grade are suitable. The ASTM A563 Nut Compatibility Chart has a complete list of specifications.

TYPE 1

Medium carbon and alloy steel

TYPE 2

Withdrawn in 2002

TYPE 3

Weathering steel

M

Metric A490

SC

Slip critical connection

N

Bearing type connection with threads included in the shear plane

X

Bearing type connection with threads excluded from the shear plane

Size

Tensile, ksi

Yield, ksi

Elong %, min

RA %, min

1/2 – 1

150 - 173 min

130 min

14

40

Nuts

Washers

Type 1

Type 3

Type 1

Type 3

A563DH

A563DH3

F436-1

F436-3

Note: Nuts conforming to A194-2H are a suitable substitute for use with A490 heavy hex structural bolts.

The bolts shall not be coated by hot-dip zinc coating, mechanical deposition, or electroplating with zinc or other metallic coatings due to the potential for hydrogen embrittlement.

Each sample representative of the lot shall be magnetic particle inspected for longitudinal discontinuities and transverse cracks.

A

Low carbon steel, hex or heavy hex

B

Low carbon steel, hex or heavy hex

C

Carbon steel, quench & tempered, heavy hex

D

Carbon steel, quench & tempered, heavy hex

DH

Carbon steel, quench & tempered, heavy hex

C3

Weathering steel, quench & tempered, heavy hex

DH3

Weathering steel, quench & tempered, heavy hex

Grade

Style

Size, in.

Proof Load, ksi

Hardness, HBN

Black

Galvanized

A

Hex

1/4 - 1-1/2

90

68

116 - 302

Heavy Hex

1/4 - 4

100

75

116 - 302

B

Heavy Hex

1/4 - 1

133

100

121 - 302

Heavy Hex

1-1/8 - 1-1/2

116

87

121 - 302

C / C3

Heavy Hex

1/4 - 4

144

144

143 - 352

D

Heavy Hex

1/4 - 4

150

150

248 - 352

DH / DH3

Heavy Hex

1/4 - 4

175

150

248 - 352

For UNC, 8UN, 6UN, and Coarse Pitch Threads

Grade Identification Marking

Specification

Material

Nominal Size, In.

Proof Load Stress, ksi

Hardness Rockwell

See Note

Min

Max

No Mark

ASTM A563 Grade O

Carbon Steel

1/4 - 1-1/2

69

B55

C32

2,3

ASTM A563 Grade A

Carbon Steel

1/4 - 1-1/2

90

B68

C32

2,3

ASTM A563 Grade B

Carbon Steel

1/4 - 1

120

B69

C32

2,3

>1 - 1-1/2

105

ASTM A563 Grade C

Carbon Steel, may be Quenched and Tempered

1/4 - 4

144

B78

C38

4

ASTM A563 Grade C3

Atmospheric Corrosion Resistant Steel, may be Quenched and Tempered

1/4 - 4

144

B78

38

4,6

ASTM A563 Grade D

Carbon Steel, may be Quenched and Tempered

1/4 - 4

150

B84

C38

5

ASTM A563 Grade DH

Carbon Steel, Quenched and Tempered

1/4 - 4

175

C24

C38

5

ASTM A563 Grade DH3

Atmospheric Corrosion Resistant Steel, Quenched and Tempered

1/4 - 4

175

C24

C38

4,6

NOTES:

•  In addition to the indicated grade marking, all grades, except A563 grades O, A, and B, must be marked for manufacturer identification.

•  Nuts are not required to be marked unless specified by the purchaser. When marked, the identification marking shall be the grade letter O, A, or B.

•  Properties shown are those of nonplated or noncoated coarse thread nuts.

•  Properties shown are those of coarse thread heavy hex nuts.

•  Properties shown are those of coarse thread heavy hex nuts. Other nuts styles and fine threads may apply.

•  The nut manufacturer, at his option, may add other markings to indicate the use of atmospheric corrosion resistant steel.

Nominal Nut Size,
in. and Pitch

Diametral Allowance,
in.

Pitch Diameter

Min

Max

0.250 - 20

0.016

0.2335

0.2384

0.312 - 18

0.017

0.2934

0.2987

0.375 - 16

0.017

0.3514

0.3571

0.437 - 14

0.018

0.4091

0.4152

0.500 - 13

0.018

0.4680

0.4745

0.0562 - 12

0.020

0.5284

0.5352

0.625 - 11

0.020

0.5860

0.5932

0.750 - 10

0.020

0.7050

0.7127

0.875 - 9

0.022

0.8248

0.8330

1.000 - 8

0.024

0.9428

0.9516

1.125 - 8

0.024

1.0678

1.0768

1.125 - 7

0.024

1.0562

1.0656

1.250 - 8

0.024

1.1928

1.2020

1.250 - 7

0.024

1.1812

1.1908

1.375 - 8

0.027

1.3208

1.3301

1.375 - 6

0.027

1.2937

1.3041

1.500 - 8

0.027

1.4458

1.4553

1.500 - 6

0.027

1.4187

1.4292

1.750 - 5

0.050

1.6701

1.6817

2.000 - 4.5

0.050

1.9057

1.9181

2.250 - 4.5

0.050

2.1557

2.1683

2.500 - 4

0.050

2.3876

2.4011

2.750 - 4

0.050

2.6376

2.6513

3.250 - 4

0.050

3.1376

3.1517

3.500 - 4

0.050

3.3876

3.4019

3.750 - 4

0.050

3.3876

3.4019

4.000 - 4

0.050

3.8876

3.9023

.

ASTM F1554

The ASTM F1554 specification covers anchor bolts designed to anchor structural supports to concrete foundations. F1554 anchor bolts can take the form of either headed bolts, straight rods, or bent anchor bolts. The three grades 36, 55, and 105 designate the minimum yield strength (ksi) of the anchor bolt. The bolts can be either cut or roll threaded and a weldable grade 55 can be substituted for grade 36 at the supplier's option. Color coding on the end - 36 blue, 55 yellow, and 105 red – helps facilitate easy identification in the field. Permanent manufacturer and grade marking is allowed under the S2 supplementary requirements.

Applications for F1554 anchor bolts include columns in structural steel framed buildings, traffic signal and street lighting poles, and overhead highway sign structures to name just a few.

GRADES

MECHANICAL PROPORTIES

RECOMMENDED NUTS and WASHERS

ASTM F2329

ASTM F2329 covers the requirements for hot-dip zinc coating applied to carbon steel and alloy steel bolts, screws, washers, nuts, and special threaded fasteners applied by the hot-dip coating process . 

This specification was developed in 2005, but is not yet widely used since many of the ASTM specification covering threaded fasteners do not reference it.  As soon as these specifications are updated to reference the ASTM F2329 specification, it will likely become much more prevalent than ASTM A153 which is the specification that is currently used to cover hot-dip galvanizing of bolts. 

ASTM A123 is a related hot-dip galvanizing specification covering iron and steel products made from rolled pressed and forged shapes, castings, plates, bars, and strips.

1. The availability of A563 grade DH nuts in nominal sizes 3/4" and larger is very limited and generally available only on special orders of 50,000 or more. For smaller quantities, ASTM A194 grade 2H should be considered.