Specifications

ASTM F3125-15a

Scope
The ASTM F3125-15 specification consolidates and covers high strength structural bolts, both Hex Head & TC Bolts, that previously fell under A325, A490, F1852 & F2280. Bolts manufactured under this specification come in sizes from 1/2″ to 1-1/2″ inclusive. For bolts that do not fall under the diameter and length requirements for the above grades but have a similar mechanical values, see either ASTM Spec A354-BD or A449.

3.Ordering Information
NOTE 2—Bolts are sometimes detailed with names such as A325 HS, A325 SC, A325 X or A490 N. These names relate to connection design and bolt installation, but do not change the manufacturing requirements and are preferably not shown on bolt orders.

F3125-15 Classification

Grade	Min Strength	Type		Head Style
A325	120 ksi	1	3	Hex Head
F1852	120 ksi	1	3	Twist-off (TC)
A490	150 ksi	1	3	Hex Head
F2280	150 ksi	1	3	Twist-off (TC)
Source: F3125-15

Heavy Hex Bolts may be ordered individually, packaged with nuts and washers or as assemblies and may be re lubricated in the field, using a stick wax or bee’s wax.

Tension Control Bolts are only shipped as an assembly of 1 bolt, 1 nut and 1 washer. TC Bolts MAY NOT BE RE LUBRICATED IN THE FIELD and may only be re lubricated by the manufacturer.

Table 1: Dimensions, Threads, Marking Matching Components

	120 ksi Min Tensile		150 ksi Min Tensile
	Type 1	Type 3	Type 1	Type 3
Hex Head Bolt Dimensions, ASME ᴮ	B18.2.6	B18.2.6	B18.2.6	B18.2.6
Hex Head Bolt Thread Fit ASME ᴮ	B1.1 UNC 2A	B1.1 UNC 2A	B1.1 UNC 2A	B1.1 UNC 2A
Hex Head Bolt Grade Marking ᴬᴰ	A325	`A325`	A490	`A490`
Twist-Off Bolt Dimensions, ASME ᴮ	B18.2.6	B18.2.6	B18.2.6	B18.2.6
Twist-Off Bolt Thread Fit ASME ᴮ	B1.1 UNC 2A	B1.1 UNC 2A	B1.1 UNC 2A	B1.1 UNC 2A
Twist-Off Bolt Grade Marking ᴬᴰ	A325TC	`A325TC`	A490TC	`A490TC`
Twist-Off Bolt Alt Marking ᴬᶜ	A325	`A325`	A490	`A490`
Recommended Plain Nut	A563 DH	A563 DH3	A563 DH	A563 DH3
Recommended Alternative Nut	DH3, D, C, C3	C3
Recommended Coated Nut	A563 DH	A563 DH3	A563 DH	A563 DH3
Flat, Bevel or Thick Washer	F436-1	F436-3	F436-1	F436-3
Source: ASTM F3125-15

Table 2: Chemical Requirments

Heat Analysis	120 ksi Min, Grade A325 & F1852				150 ksi Min, Grade A490 & F2280
	Type 1	Type 3			Type 1	Type 3
	Carbon or Alloy ᴰ with or without Boron	Composition A	Composition B	Based on Corrosion Index ᴱ	Alloy ᴰ Steel with or without Boron	Based On Corrosion Index ᴱ
Carbon	0.30 – 0.52	0.33 – 0.40	0.38 – 0.48	0.3 – 0.52 max	0.3 – 0.48 ᴬ	0.3 – 0.53
Manganese	0.60 min	0.90 – 1.20	0.70 – 0.90	0.6 min	0.6 min	0.6 min
Phosphorus max	0.035	0.035	0.035	0.035	0.035	0.035
Sulfur max	0.04	0.04	0.04	0.04	0.04	0.04
Silicon	0.15 – 0.30	0.15 – 0.30	0.3 – 0.5	ʙ	ʙ	ʙ
Boron	0.003 max	ʙ	ʙ	ʙ	0.003 max	ʙ
Copper	ʙ	0.25 – 0.45	0.2 – 0.4	0.2 – 0.60 ʙ	ʙ	0.2 – 0.6 ᴱ
Nickel	ʙ	0.25 – 0.45	0.5 – 0.8	0.20 ʙ,c min	ʙ	0.2 ᴱ,ᶠmin
Chromium	ʙ	0.45 – 0.65	0.5 – 0.75	0.45 ʙ min	ʙ	0.45 ᴱ min
Vanadium	ʙ	ʙ	ʙ	ʙ	ʙ	ʙ
Molybdenum	ʙ	ʙ	0.063 max	0.10 ʙ,c min	ʙ	0.1 ᴱ,ᶠ min
Titanium	ʙ	ʙ	ʙ	ʙ	ʙ	ʙ
Source ASTM F3125-15

Table 3: Number of Tests and Test Method or Criteria

Table 3 Number of Tests & Test Method or Criteria
All Grades, Types, Styles	Sample Size Per Lot	Test Method	Notes
Tensile Strength	F1470	F606/F606M	Wedge or Axial Full Size. Machined See 8.1.1
Proof Load	F1470	F606/F606M	Method 1 or 2 optional. See 8.1.2
Hardness	F1470	F606/F606M
Dimensions and Thread Fit	ASME B18.18	ASME B18.2.6 B1.1 2A
Surface Discontinuities	F1470	F788
Coating Weight/Thickness	F1470 ᴮ	Product Specification
150 ksi grades all types/styles
Magnetic Partical	F1470	F788	Guide E709 of Practice E1444/E1444M
Carburization/Decarburization	At least 1	F2328
All Twist Off Assemblies
Fastener Tension	F1470	This Standard
Rotational Capacity ᴬ	F1470	Annex A2
Source: ASTM F3125-15

Table 4: Tensile Strength Requirements for Bolts Tested Full Size

		120 ksi – A325 (Hex) & F1852 (Twist-Off)			150 ksi – A490 (Hex) & F2280 (Twist-Off)
Diameter	Stress Area in ²	Tensile min lbf	Proof Load min lbf	Proof Load min lbf	Tensile min lbf	Tensile max lbf	Proof Load min lbf	Proof Load min
1/2″	0.142	17,050	12,050	13,050	21,300	24,600	17,050	18,500
5/8″	0.226	27,100	19,200	20,800	33,900	39,100	27,100	29,400
3/4″	0.334	40,100	28,400	30,700	50,100	57,800	40,100	43,400
7/8″	0.462	55,450	39,250	42,500	69,300	79,950	55,450	60,100
1″	0.606	72,700	51,500	55,700	90,900	104,850	72,700	78,800
1-1/8″	0.763	91,600	64,900	70,250	114,450	132,000	91,600	99,200
1-1/4″	0.969	116,300	82,400	89,200	145,350	167,650	116,300	126,000
1-3/8″	1.155	138,600	98,200	106,300	173,250	199,850	138,600	150,200
1-1/2″	1.105	168,600	119,500	129,300	210,750	243,100	168,600	182,600
Above values based on		120,000psi	85,000psi	92,000psi	150,000psi	173,000psi	120,000psi	130,000psi
Source: ASTM F3125-15

Table 5: Tensile Strength Requirements For Specimens Machined from Bolts

	Tensile min	Tensile max	Yield min	Elongation in 4D min	Reduction of Area, min
120 ksi A325 & F1852	120000 psi	NA	92,000 psi	0.14	0.35
150 ksi A490 & F2280	150000 psi	173,000 psi	130,000 psi	0.14	0.4
Source: ASTM F3125-15

Table 6 Hardness Requirments for Bolts

		120 ksi Tensile, Grde A325 & F1852				150 ksi Tensile, Grade A490 & F2280
		Brinell HB		Rockwell HRC		Brinell HB		Rockwell HRC
Diameter	Length	Min	Max	Min	Max	Min	Max	Min	Max
≤ 1″	Less than 2 x Diameter	253	319	25	34	311	352	33	38
≤ 1″	2 x Diameter and longer	–	319	–	34	–	352	–	38
Over 1″	Less than 3 x Diameter	253	319	25	34	311	352	33	38
Over 1″	3 x Diameter and Longer	–	319	–	34	–	352	–	38
Source: ASTM F3125-15

F3125-15 Table 7 Twist-Off Style Assembly Installation Tension Test (Minimum Tension, lbf)

Diameter	F1852	F2280
1/2″	12,550	15,650
5/8″	19,900	24,900
3/4″	29,450	36,800
7/8″	40,750	50,950
1″	53,450	66,800
1-1/8″	67,350	84,100
1-1/4″	85,500	106,850
Source: ASTM F3125-15

ASTM F3125-15 approved Jan. 1st, 2015.

St. Louis Screw & Bolt