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ASTM A307 TECHNICAL DATA

 

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Technical Data: ASTM A307 Chemical Requirements for Grades A and B Bolts, Studs, and Threaded Rod ASTM A307 Hardness Requirements for Bolts, Studs, and Threaded Rods ASTM A307 Tensile Requirements for Full-Size Bolts, Studs, and Threaded Rod ASTM A307 Tensile Requirements for Machined Specimens ASTM A307 Sample Sizes and Acceptance Numbers for Inspection of Hot-Dip or Mechanically Deposited Zinc-Coated Threads

Chemical Requirements for Grades A and B Bolts, Studs and Threaded Rod

  Heat Analysis Product Analysis
Carbon, max 0.29 0.33
Manganese, max 1.20 1.25
Phosphorus,   max 0.04 0.041
Sulfur, max    
Grade A 0.15 A
Grade B 0.05 0.051

Hardness Requirements for Bolts, Studs, and Threaded Rod

Grade Nominal
Length, in. 		HardnessA
Brinell Rockwell B
min max min max
A Less than 3 × diaB 121 241 69 100
3 × dia and longer   241   100
B Less than 3 × diaB 121 212 69 95
3 × dia and longer   212   95
AAs measured anywhere on the surface or through the cross section.
BAlso bolts with drilled or undersize heads. These sizes and bolts with modified heads shall meet the minimum and maximum hardness as hardness is the only requirement.

Tensile Requirements for Full-Size Bolts, Studs, and Threaded Rod

Bolt
Size, in.		 Threads
per inch		 Stress
Area, A
in.2		 Tensile Strength, lbfB
Grade
A, min C		 Grade B
minD maxD
1⁄4 20 0.0318 1,900 1,900 3,180
5⁄16 18 0.0524 3,100 3,100 5,240
3⁄8 16 0.0775 4,650 4,650 7,750
7⁄16 14 0.1063 6,350 6,350 10,630
1⁄2 13 0.1419 8,500 8,500 14,190
9⁄16 12 0.182 11,000 11,000 18,200
5⁄8 11 0.226 13,550 13,550 22,600
3⁄4 10 0.334 20,050 20,050 33,400
7⁄8 9 0.462 27,700 27,700 46,200
1 8 0.606 36,350 36,350 60,600
1 1⁄8 7 0.763 45,800 45,800 76,300
1 1⁄4 7 0.969 58,150 58,150 96,900
1 3⁄8 6 1.155 69 300 69,300 115,500
1 1⁄2 6 1.405 84 300 84,300 140,500
1 3⁄4 5 1.90 114,000 114,000 190,000
2 4½ 2.50 150,000 150,000 250,000
2 1⁄4 4½ 3.25 195,000 195,000 325,000
2 1⁄2 4 4.00 240,000 240,000 400,000
2 3⁄4 4 4.93 295,800 295,800 493,000
3 4 5.97 358,200 358,200 597,000
3 1⁄4 4 7.10 426,000 426,000 710,000
3 1⁄2 4 8.33 499,800 499,800 833,000
3 3⁄4 4 9.66 579,600 579,600 966,000
4 4 11.08 664,800 664,800 1,108,000
B1 lbf = 4.448 N.
CBased on 60 ksi (414 MPa).
DBased on 60–100 ksi (414–690 MPa).

Tensile Requirements for Machined Specimens

  Grade A Grade B
Tensile strength, ksi 60 min 60-100
Yield point, min ksi … …
Elongation in 2 in.,
     min, %		 18 18

Sample Sizes and Acceptance Numbers for Inspection of Hot-Dip or Mechanically Deposited Zinc-Coated Threads

Lot Size Sample SizeA Acceptance Number
2 to 90 13 1
91 to 150 20 2
151 to 280 32 3
281 to 500 50 5
501 to 1,200 80 7
1,201 to 3,200 125 10
3,201 to 10,000 200 14
10,001 and over 315 21
AInspect all bolts in the lot if the lot size is less than the sample size.