ASTM A490/A490M Type 1 Heavy Hex Structural Bolts

ASTM A490/A490 Type 1 Heavy Hex Structural Bolts

ASTM A490 Type 1 is a high tensile bolting grade manufactured from high tensile alloy steel intended for use in structural connections. Type 1 Bolts are produced from 1/2" to 1-1/2" in imperial size as per ASTM A490 & from M12 to M36 in metric size as per ASTM A490M. These A490 type 1 bolts can be supplied with zinc, cadmium or dacromet coatings in accordance to ASTM F1136. Ferrobend stocks raw material for quick manufacturing and shorter delivery times. We supply Type 1 boltings with EN 10204 type 3.1 certification. Please browse through the page for complete detail on chemical requirement, hardness requirement, tensile requirement, recommended nuts and washers for A490/A490M Type 1 Bolts.

ASTM A490 Type 1 Chemical Composition

Element Heat Analysis % Product Analysis %
Carbon    
For sizes through 1-3/8" 0.30 - 0.48 0.28 - 0.50
For sizes 1-1/2" 0.35 - 0.53 0.33 - 0.55
Phosphorus, max 0.040 0.045
Sulfur, max 0.040 0.045

ASTM A490M Type 1 Mechanical Requirement (Metric)

Nominal Diameter, mm Tensile Strength, min, Mpa Yield Strength, min, Mpa Elongation in 4D, min, % Reduction in Area, min, %
M12 to M36, Inclusive 1040 - 1210 940 14 40

ASTM A490 Type 1 Mechanical Requirement (Imperial)

Nominal Diameter, inch Tensile Strength, min, ksi Yield Strength, min, ksi Elongation in 4D, min, % Reduction in Area, min, %
1/2" to 1-1/2", Inclusive 150 - 173 130 14 40

Hardness Requirements for ASTM A490M Bolts (Metric)

Bolt Size, mm Bolt Length*, mm Brinell Rockwell C
min max min max
M12 to M24, inclusive Less than 2D 311 352 33 39
M12 to M24, inclusive 2D and over -- 352 -- 39
M25 to M36, Inclusive Less than 3D 311 352 33 39
M25 to M36, Inclusive 3D and over -- 352 -- 39
Note* : Heavy Hex Structural Bolts M24 and smaller and shorter than 2D are subject only to minimum and maximum hardness. Heavy hex structural bolts larger than M24 through M36 inclusive in diameter and shorter than 3D are subject only to minimum and maximum hardness.

Hardness Requirements for ASTM A490 Bolts (Imperial)

Bolt Size, mm Bolt Length*, mm Brinell Rockwell C
min max min max
1/2" to 1", inclusive Less than 2D* 311 352 33 39
1/2" to 1", inclusive 2D and over -- 352 -- 39
1-1/8" to 1-1/2", inclusive Less than 3D 311 352 33 39
1-1/8" to 1-1/2", inclusive 3D and over -- 352 -- 39
Note* : Heavy Hex Structural Bolts 1" and smaller and shorter than 2D are subject only to minimum and maximum hardness. Heavy hex structural bolts larger than 1" through 1-1/2" inclusive in diameter and shorter than 3D are subject only to minimum and maximum hardness.

ASTM A490/A490M Type 1 Heat Treatment

Type 1 and Type 3 bolts shall be heat treated by quenching in oil from the austenitic temperature and then tempered by reheating to a temperature of not less then 800°F.

Recommended Nuts

Bolt Type and Finish Nut Class and Finish Specification
Plain (noncoated) ASTM A563-DH, DH3, plain (uncoated)
Weathering steel ASTM A563-DH3, weathering steel

Recommended Washers

Bolt Type and Finish Washer Finish
Plain (noncoated) Plain (uncoated)
Weathering steel Weathering steel

ASTM A490/A90M Type 1 Bolt Marking

Grade Marking
A490 / A490M Type 1 A490 / A490M