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 2 Nut Grades

Grade Tensile Class Raw Material

ASTM A194 Grade 2 Chemical Components

Grade Material UNS
Number
C, % Mn, % Ph, % S, % Si, % Cr, % Ni, % Mo, % Ti, % Cb & Ta, % N, % Other Elements, %
2 Carbon   0.40 min 1.000 0.040 0.050 0.400 - - - - - - -

ASTM A194 Hardness Requirement

Grade & Type Brinell Hardness Rockwell Hardness
C Scale B Scale
2 159-352 - 84 min

ASTM A194 Proof Load (Inch Series)

Nominal Size, inch Threads per inch Stress Area inch Proof Load, lbf
GRADE 2
Heavy Hex Hex
1/4" 20 0.0316 4130 3820
5/16" 18 0.0524 6810 6290
3/8" 16 0.0774 10080 9300
7/16" 14 0.1063 13820 12760
1/2" 13 0.1419 18450 17030
9/16" 12 0.1820 23660 21840
5/8" 11 0.2260 29380 27120
3/4" 10 0.3340 43420 40080
7/8" 9 0.4620 60060 55440
1" 8 0.606 78780 72720
1 1/8" 8 0.7900 102700 94800
1 1/4" 8 1.0000 130000 120000
1 3/8" 8 1.2330 160200 148000
1 1/2" 8 1.492 194000 170040

ASTM A194 Grade 2 Marking

Grade Type Hot Forged or Cold Punched Nuts Nuts Machined from Bar Stock
2 2 2B