Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High Pressure or High Temperature Service, or both.
ASTM A194 specification covers a variety of carbon, alloy, and martensitic stainless steel nuts in the size range 1/4 through 4
in. and metric M6 through M100 nominal. It also covers austenitic stainless steel nuts in the size range 1/4 in. and M6
nominal and above. These nuts are intended for high-pressure or high-temperature service, or both.
ASTM A194 Grade 3 Nut Grades
Grade |
Tensile Class |
Raw Material |
ASTM A194 Grade 3 Chemical Components
Grade |
Material |
UNS Number |
C, % |
Mn, % |
Ph, % |
S, % |
Si, % |
Cr, % |
Ni, % |
Mo, % |
Ti, % |
Cb & Ta, % |
N, % |
Other Elements, % |
3 |
Type 501 |
|
0.10 min |
1.000 |
0.040 |
0.030 |
1.000 |
4.0-6.0 |
- |
0.40-0.65 |
- |
- |
- |
- |
ASTM A194 Grade 3 Hardness Requirement
Grade & Type |
Brinell Hardness |
Rockwell Hardness |
C Scale |
B Scale |
ASTM A194 Grade 3 Proof Load (Inch Series)
Nominal Size, inch |
Threads per inch |
Stress Area inch |
Proof Load, lbf |
GRADE 2, 2HM, 6, 6f, 7M |
Grade 2H, 4, 7, 16 |
All Types of Grade 8 |
Heavy Hex |
Hex |
Heavy Hex |
Hex |
Heavy Hex |
Hex |
ASTM A194 Grade 3 Marking
Grade Type |
Hot Forged or Cold Punched Nuts |
Nuts Machined from Bar Stock |