MF FASTENER INDUSTRIES LLC Manufacturer of anchor bolts, studs & plate washers · Importer & stockist of fasteners

Technical datasheet ASTM F3125 / F3125M — Grade A490 & A490M heavy hex structural bolt

Reference only — for design, verification or contractual purposes refer to the current issue of the original standard. MF Fastener Industries LLC · sales@mfindllc.com · +971 6 767 2469 · mfindllc.com

HOME / DATA & DRAWINGS / A490 / A490M

Dimensional datasheet

ASTM A490 structural bolt

Heavy hex structural bolt, alloy steel, quenched and tempered, 150 ksi / 1040 MPa class. The high-strength grade above A325, for connections where fewer or smaller bolts are needed.

View the product Get a quote

D nominal diameterF width across flatsH head heightL length under head

Dimensions

inches

Imperial sizes, UNC thread, dimensions to ASME B18.2.6. Head dimensions are identical to A325 — only the material, strength and marking differ.

Size	Threads/in	F — across flats	Spanner size	H — head height	Thread length	Tensile strength min
1/2"	13 UNC	7/8"	7/8"	5/16"	1"	150 ksi
5/8"	11 UNC	1-1/16"	1-1/16"	25/64"	1-1/4"	150 ksi
3/4"	10 UNC	1-1/4"	1-1/4"	15/32"	1-3/8"	150 ksi
7/8"	9 UNC	1-7/16"	1-7/16"	35/64"	1-1/2"	150 ksi
1"	8 UNC	1-5/8"	1-5/8"	39/64"	1-3/4"	150 ksi
1-1/8"	7 UNC	1-13/16"	1-13/16"	11/16"	2"	150 ksi
1-1/4"	7 UNC	2"	2"	25/32"	2"	150 ksi
1-3/8"	6 UNC	2-3/16"	2-3/16"	27/32"	2-1/4"	150 ksi
1-1/2"	6 UNC	2-3/8"	2-3/8"	15/16"	2-1/4"	150 ksi

A325 and A490 are withdrawn as standalone standards

ASTM withdrew A325, A325M, A490 and A490M in 2016. All four are now grades within ASTM F3125 / F3125M. The product is unchanged and the head is still marked A325 or A490, so a drawing calling for A325 is satisfied by F3125 Grade A325.

A490 must not be hot-dip galvanized

ASTM F3125 prohibits hot-dip galvanizing of A490 and A490M. At this strength the risk of hydrogen embrittlement and delayed fracture is unacceptable.

If the connection needs corrosion protection, the options are weathering steel Type 3, an approved coating system, or a change of grade. Ask before ordering — a galvanized A490 should not exist.

Re-use is not permitted

A490 bolts are tightened past yield and must not be re-used — a bolt backed off and re-tightened has an unknown clamp load. Order spares.

Metric — Grade A490M

ASTM F3125M

Size	Pitch	F — across flats	Spanner size	H — head height	Tensile min
M16	2.00	27 mm	27 mm	10.0 mm	1040 MPa
M20	2.50	34 mm	34 mm	12.5 mm	1040 MPa
M22	2.50	36 mm	36 mm	14.0 mm	1040 MPa
M24	3.00	41 mm	41 mm	15.0 mm	1040 MPa
M27	3.00	46 mm	46 mm	17.0 mm	1040 MPa
M30	3.50	50 mm	50 mm	18.7 mm	1040 MPa
M36	4.00	60 mm	60 mm	22.5 mm	1040 MPa

A490M carries the same prohibition on hot-dip galvanizing as A490.

Mechanical properties

F3125 / F3125M

Property	A490 (imperial)	A490M (metric)
Tensile strength	150 – 173 ksi	1040 – 1210 MPa
Yield strength min	130 ksi	940 MPa
Hardness	33 – 38 HRC	33 – 38 HRC
Elongation min	14%	14%
Head marking	A490 and manufacturer's mark	A490M and manufacturer's mark

Note the tensile strength has a maximum as well as a minimum. Over-strength material is as much a rejection as under-strength.

At a glance

Standard	ASTM F3125 / F3125M Grade A490 / A490M
Withdrawn standard	ASTM A490 · A490M (2016)
Head	Heavy hexagon
Thread	UNC imperial · metric coarse
Class	150 ksi / 1040 MPa
Galvanizing	Not permitted
Matching nut	ASTM A563 Grade DH or DH3 · A563M 10S or 10S3
Matching washer	ASTM F436 / F436M hardened
Lower grade	A325 / A325M

Supply

Imported and held in stock, sourced from established mills and supplied from our warehouse in Umm Al Quwain.

Anchor bolts, studs and plate washers are manufactured at our own plant. This item is not.

Finish

Plain	Black, oiled — the normal supply
Weathering steel	Type 3, for uncoated weathering assemblies
Hot-dip galvanized	Not permitted
Certification	Mill certificate against lot and heat number

Testing

Dimensional and thread inspection is carried out in our own plant on calibrated instruments. Tensile, hardness and chemical testing is carried out by independent UAE-accredited laboratories.

Reference only

This datasheet is published for reference. Dimensions and property values are reproduced in good faith from published standards, but for design, verification or contractual purposes always refer to the current issue of the original standard.

If a figure here conflicts with the standard, the standard governs.

Need a quotation?

Send the size, length, Type and quantity, with the nuts and washers you need as a matched set. If a coating is required, tell us the environment and we will advise.