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| IdentificationGrade Mark | Specification | FastenerDescription | Material | Nominal SizeRange (in.) | Mechanical Properties | ||
| Proof Load(psi) |
Yield StrengthMin (psi) |
Tensile StrengthMin (psi) |
|||||
 NoGradeMark |
SAE J429Grade 1 | Bolts,Screws,Studs | Low or Medium Carbon Steel |
1/4 thru 1-1/2 |
33,000 | 36,000 | 60,000 |
| ASTM A307Grades A&B | Low Carbon Steel |
1/4 thru 4 | – | – | |||
| SAE J429Grade 2 | Low or Medium Carbon Steel |
1/4 thru 3/4 Over 3/4 to 1-1/2 |
55,00033,000 | 57,00036,000 | 74,00060,000 | ||
| NoGradeMark |
SAE J429Grade 4 | Studs | Medium Carbon Cold Drawn Steel |
1/4 thru 1-1/2 |
– | 100,000 | 115,000 |
| B5 |
ASTM A193Grade B5 | AISI 501 | 1/4 Thru 4 | – | 80,000 | 100,000 | |
| B6 |
ASTM A193Grade B6 | AISI 410 | 85,000 | 110,000 | |||
| B7 |
ASTM A193Grade B7 | AISI 4140, 4142, OR 4105 |
1/4 thru 2-1/2Over 2-1/2 thru 4Over 4 thru 7 | –—- | 105,00095,00075,000 | 125,000115,000100,000 | |
| B16 |
ASTM A193Grade B16 | CrMoVa Alloy Steel |
105,00095,00085,000 | 125,000115,000100,000 | |||
| B8 |
ASTM A193Grade B8 | AISI 304 | 1/4 and larger | – | 30,000 | 75,000 | |
| B8C |
ASTM A193Grade B8C | AISI 347 | |||||
| B8M |
ASTM A193Grade B8M | AISI 316 | |||||
| B8T |
ASTM A193Grade B8T | Bolts,Screws,Studs for High-Temperature Service | AISI 321 | 1/4 and larger |
– | 30,000 | 75,000 |
| B8 |
ASTM A193Grade B8 | AISI 304Strain Hardened | 1/4 thr 3/4Over 3/4 thru 1Over 1 thru 1-1/4Over 1-1/4 thru 1-1/2 | –—— | 100,00080,00065,000
50,000 |
125,000115,000105,00
0100,000 |
|
| B8C |
ASTM A193Grade B8C | AISI 347Strain Hardened | |||||
| B8M |
ASTM A193Grade B8M | AISI 316Strain Hardened | 95,00080,00065,000
50,000 |
110,000100,00095,00
090,000 |
|||
| B8T |
ASTM A193Grade B8T | AISI 321Strain Hardened | 100,00080,00065,000
50,000 |
125,000115,000105,000
100,000 |
|||
| L7 |
ASTM A320Grade L7 | Bolts,Screws,Studs for Low-Temperature Service | AISI 4140,4142 or 4145 | 1/4 thru 2-1/2 | – | 105,000 | 125,000 |
| L7A |
ASTM A320Grade L7A | AISI 4037 | |||||
| L7B |
ASTM A320Grade L7B | AISI 4137 | |||||
| L7C |
ASTM A320Grade LC7 | AISI 8740 | |||||
| L43 |
ASTM A320Grade L43 | AISI 4340 | 1/4 thru 4 | – | 105,000 | 125,000 | |
| B8 |
ASTM A320Grade B8 | Bolts,Screws,Studs for Low-Temperature Service | AISI 304 | 1/4 and larger | – | 30,000 | 75,000 |
| B8C |
ASTM A320Grade B8C | AISI 347 | |||||
| B8T |
ASTM A320Grade B8T | AISI 321 | |||||
| B8F |
ASTM A320Grade B8F | AISI 303or 303Se | |||||
| B8M |
ASTM A320Grade B8M | AISI 316 | |||||
| B8 |
ASTM A320Grade B8 | AISI 304 | 1/4 thru 3/4Over 3/4 thru 1Over 1 thru 1-1/4Over 1-1/4 thru 1-1/2 | –—— | 100,00080,00065,00
50,00 |
100,00080,00065,00
50,00 |
|
| B8C |
ASTM A320Grade B8C | AISI 347 | |||||
| B8F |
ASTM A320Grade B8F | AISI 303or 303Se | |||||
| B8M |
ASTM A320Grade B8M | AISI 316 | |||||
| B8T |
ASTM A320Grade B8T | AISI 321 | |||||
 |
SAE J429Grade 5 | Bolts,Screws,Studs | Medium Carbon Steel, Quenched and Tempered | 1/4 thru 1Over 1 to 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 |
| ASTM A449 | 1/4 thru 1Over 1 to 1-1/2Over 1-1/2 thru 3 | 85,00074,000
55,000 |
92,00081,00058,000 | 120,000105,00090,000 | |||
 |
SAE J429Grade 5.1 | Sems | Low or Medium Carbon Steel, Quenched and Tempered |
No. 6thru 3/8 | 85,000 | – | 120,000 |
 |
SAE J429Grade 5.2 | Bolts,Screws,Studs | Low Carbon Martensitic Steel, Quenched and Tempered |
1/4 thru 1 | 85,000 | 92,000 | 120,000 |
| A325 |
ASTM A325Type 1 | High StrengthStructural Bolts | Medium Carbon Steel, Quenched and Tempered |
1/2 thru 11-1/8 thru 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 |
| A325 |
ASTM A325Type 2 | Low Carbon Martensitic Steel, Quenched and Tempered |
1/2 thru 1 | 85,000 | 92,000 | 120,000 | |
| A325 |
ASTM A325Type 3 | Atmospheric Corrosion Resisting Steel, Quenched and Tempered |
1/2 thru 11-1/8 thru 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 | |
 BB |
ASTM A354Grade BB | Bolts,Studs | Alloy Steel, Quenched and Tempered | 1/4 thru 2-1/22-3/4 thru 4 | 80,00075,000 | 83,00078,000 | 105,000100,000 |
 BC |
ASTM A354Grade BC | 105,00095,000 | 109,00099,000 | 125,000115,000 | |||
 |
SAE J429Grade 7 | Bolts,Screws, | Medium Carbon Alloy Steel, Quenched and Tempered 4 |
1/4 thru 1-1/2 |
105,000 | 115,000 | 133,000 |
 |
SAE J429Grade 8 | Bolts,Screws,Studs | Medium Carbon Alloy Steel, Quenched and Tempered |
1/4 thru 1-1/2 | 120,000 | 130,000 | 150,000 |
| ASTM A354Grade BD | Alloy Steel, Quenched and Tempered 4 |
||||||
| No GradeMark |
SAE J429Grade 8.1 | Studs | Medium Carbon Alloy or SAE 1041 Modified Elevated Temperature Drawn Steel |
1/4 thru 1-1/2 |
120,000 | 130,000 | 150,000 |
| A490 |
ASTM A490 | High Strength Structural Bolts |
Alloy Steel, Quenched and Tempered |
1/2 thru 1-1/2 |
120,000 | 130,000 | 150,000 min170,000 max |
| No GradeMark |
ISO R898Class 4.6 | Bolts,Screws,Studs | Medium Carbon Steel, Quenched and Tempered | All Sizesthru 1-1/2 | 33,000 | 36,000 | 60,000 |
| No GradeMark |
ISO R898Class 5.8 | 55,000 | 57,000 | 74,000 | |||
| 8.8or88 |
ISO R898Class 8.8 | Alloy Steel, Quenched and Tempered | 85,000 | 92,000 | 120,000 | ||
| 10.9or109 |
ISO R898Class 10.9 | 120,000 | 130,000 | 150,000 | |||
FASTENER IDENTIFICATION
MARKING
| GradeIdentificationMarking | Specification | Material | Nominal SizeIn. | ProofLoadStressksi | HardnessRockwell | SeeNote | |
| Min | Max | ||||||
 No Mark |
ASTM A563 – Grade 0 |
Carbon Steel |
1/4 thru 1-1/2 |
69 | B55 | C32 | 3,4 |
| ASTM A563 – Grade A |
Carbon Steel |
1/4 thru 1-1/2 |
90 | B68 | C32 | 3,4 | |
| ASTM A563 – Grade B | Carbon Steel | 1/4 thru 1 | 120 | B69 | C32 | 3,4 | |
| over 1 thru 1-1/2 |
105 | ||||||
 |
ASTM A563 – Grade C |
Carbon SteelMay be Quenchedand Tampered |
1/4 thru 4 | 144 | B78 | C38 | 5 |
 |
ASTM A563 – Grade C3 |
AtmosphericCorrosionResistant SteelMay be Quenchedand Tampered | 1/4 thru 4 | 144 | B78 | C38 | 5,9 |
 |
ASTM A563 – Grade D |
Carbon SteelMay be Quenchedand Tampered |
1/4 thru 4 | 150 | B84 | C38 | 6 |
 |
ASTM A563 – Grade DH |
Carbon SteelQuenchedand Tampered |
1/4 thru 4 | 175 | C24 | C38 | 6 |
 |
ASTM A563 – Grade DH3 |
AtmosphericCorrosionResistant Steel,Quenchedand Tampered | 1/4 thru 4 | 175 | C24 | C38 | 5,9 |
 |
ASTM A194 – Grade 1 |
Carbon Steel |
1/4 thru 4 | 130 | B70 | – | 7 |
 |
ASTM A194 – Grade 2 |
Medium CarbonSteel |
1/4 thru 4 | 150 | 159 | 352 | 7,8 |
 |
ASTM A194 – Grade 2H |
Medium CarbonSteel, Quenchedand Tempered |
1/4 thru 4 | 175 | C24 | C38 | 7 |
 |
ASTM A194 – Grade 2HM |
Medium CarbonSteel, Quenchedand Tempered |
1/4 thru 4 | 150 | 159 | 237 | 7,8 |
 |
ASTM A194 – Grade 4 |
Medium CarbonAlloy Steel,Quenchedand Tempered |
1/4 thru 4 | 175 | C24 | C38 | 7 |
 |
ASTM A194 – Grade 7 |
Medium CarbonAlloy Steel,Quenchedand Tempered |
1/4 thru 4 | 175 | C24 | C38 | 7 |
 |
ASTM A194 – Grade 7M |
Medium CarbonAlloy Steel,Quenchedand Tempered |
1/4 thru 4 | 150 | 159 | 237 | 7 |
| See Note 1,2 | 10 | ||||||
NOTES:
- In addition to the indicated grade
marking, all grades, except A563 grades O, A and B, must
be marked for manufacturer identification. - The markings shown for all grades of
A194 nuts are for cold formed and hot forged nuts. When
nuts are machined from bar stock the nut must be
additionally marked with the letter ‘B’. - Nuts are not required to be marked
unless specified by the purchaser. When marked, the
identification marking shall be the grade letter O, A or
B. - Properties shown are those of
nonplated or noncoated coarse thread hex nuts. - Properties shown are those of coarse
thread heavy hex nuts. - Properties shown are those of coarse
thread heavy hex nuts. - Properties shown are those of coarse
8-pitch thread heavy hex nuts. - Hardnesses are Brinell Hardness
Numbers. - The nut manufacturer, at his option,
may add other markings to indicate the use of atmospheric
corrosion resistant steel. - Specifications –
-
ASTM A563 — Carbon and Alloy Steel Nuts.
ASTM A194/A194M — Carbon and Alloy Steel Nuts for Bolts
for High Pressure and High Temperature Service.