ASTM A490 Bolts Specification

Carbon Steel, Alloy Steel And Weatherng Steel Structural Bolts, Hex Cap Screws and Studs Heat Treated to 150 ksi Minimum Tensile Strength

Related Specifications of ASTM A490 Bolting

F2482 A563 A563M A242/A242M A588/A588M A606/A606M A709/A709M

ASTM A490 Scope

Type Description
Type 1 Medium carbon alloy steel
Type 2 Withdrawn in 2002
Type 3 Weathering steel

ASTM A490 Chemical Requirements

ASTM A490 Chemical Requirements for Type 1 Bolts

Element Alloy Steel Alloy Steel with Boron Addition
Heat Analysis, % Product Analysis, % Heat Analysis, % Product Analysis, %
C For sizes through 13⁄8 in. 0.30-0.48 0.28-0.50 0.30-0.48 0.28-0.50
C For size 11⁄2 in. 0.35-0.53 0.33-0.55 0.35-0.53 0.33-0.55
P 0.040 0.045 0.040 0.045
M 0.60 0.57 0.60 0.57
S, max 0.040 0.045 0.040 0.045
B . . . . . . 0.0005-0.003 0.0005-0.003
Alloying Elements A A A A

ASTM A490 Chemical Requirements for Type 3 Bolts

Element Heat Analysis, % Product Analysis, %
C for Sizes 0.75 in. and smaller 0.20-0.53 0.19-0.55
C for Sizes larger than 0.75 in. 0.30-0.53 0.28-0.55
M, min 0.40 0.37
P, max 0.035 0.040
S, max 0.040 0.045
Cu 0.20-0.60 0.17-0.63
Cr, min 0.45 0.42
Ni, min or 0.20 0.17
Mo, min 0.15 0.14

ASTM A490 Mechinical Requirements

ASTM A490 Hardness Requirements for Bolts 1⁄2 to 11⁄2 in. Nominal Size

Size, in. Nominal Length, in. Brinell Rockwell C
min max min max
1⁄2 to
1, incl.
Less than 2D
2D and longer
311 352 33 38
. . . 352 . . . 38
Over 1 to
11⁄2, incl
Less than
3D 3D and longer
311 352 333 38
. . . 352 . . . 38

ASTM A490 Tensile Load Requirements for Bolts Tested Full-Size

Bolt Size, Threads per Inch, and Series Designation Stress Area,A in.2 Tensile Load,B lbf Proof Load,Length Measurement Method Alternative Proof Load,B lbf Yield Strength Method
min max
1⁄2 -13 UNC 0.142 21 300 24 600 17 050 18 500
5⁄8-11 UNC 0.226 33 900 39 100 27 100 29 400
3⁄4-10 UNC 0.334 50 100 57 800 40 100 43 400
7⁄8-9 UNC 0.462 69 300 79 950 55 450 60 100
1-8 UNC 0.606 90 900 104 850 72 700 78 800
11⁄8 -7 UNC 0.763 114 450 132,000 91 550 99 200
11⁄4 -7 UNC 0.969 145 350 167 650 116 300 126,000
13⁄8 -6 UNC 1.155 173 250 199 850 138 600 150 200
11⁄2 -6 UNC 1.405 210 750 243 100 168 600 182 600
  • A The stress area is calculated as follows:
    • As = 0.7854 [D − (0.9743/n)] 2
  • where:
    • As = stress area, in.2
    • D = nominal bolt size, and
    • n = threads per inch.
  • B Loads tabulated and loads to be used for tests of full-size bolts larger than 1 1⁄2 in. in diameter are based on the following:
  • Bolt Size, Threads per Inch, and Series Designation Tensile Load,B lbf Proof Load,Length Measurement Method Alternative Proof Load,B lbf Yield Strength Method
    min max
    1⁄2 to 1 1⁄2 in., incl 150,000 psi 173,000 psi 120,000 psi 130,000 psi

ASTM A490 Tensile Strength Requirements for Specimens Machined from Bolts

Bolt Size, Threads per Inch, and Series Designation Tensile Load,B lbf Yield Strength (0.2 % offset), min, psi Elongation in 2 in. or 50 mm, min, % Reduction of Area, min, %
min max
1⁄2 to 1 1⁄2 in., incl 150,000 psi 173,000 psi 130,000 psi 14 40

ASTM A490 Bolting Surface Treatment Specifications

ASTM A490 Bolting Components Marking

Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.

ASME Dimensional Standards

ASTM A490 Bolting Certifications

  • EN 10204 3.1
  • EN 10204 3.2
  • PED 2014/68/EC
  • MERKBLATT AD 2000 W2/W7/W10
  • API 20 E BSL 1/ BSL 2
  • NACE MR 0175
  • NACE MR 0103

ASTM A490 Testing Standards

ASME Threading Specifications

ASTM A490 Supplementary Requirements