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 8MLN Nut Grades

Grade Tensile Class Raw Material
B5 4-6% Chromium Ferritic Steel
B6 13% Chromium Ferritic Steel
B6X 13% Chromium Ferritic Steel
B7 Chromium Molybdenum Alloy Steel, Quenched & Tempered
B7M Chromium Molybdenum Alloy Steel, Quenched & Tempered
B16 Chromium-molybdenum-vanadium Alloy Steel, Quenched & Tempered
B8 Class 1 AISI 304 Stainless Steel, Carbide Solution Treated
B8 Class 2 AISI 304 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8A AISI 304 Stainless Steel, Carbide solution treated in the finished condition
B8C Class 1 AISI 347 Stainless Steel, Carbide Solution Treated
B8C Class 2 AISI 347 Stainless Steel, Carbide Solution Treated and Strained Hardened
B8CA AISI 347 Stainless Steel, Carbide Solution Treated in Finished Condition
B8M Class 1 AISI 316 Stainless Steel, Carbide Solution Treated
B8M Class 2 AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8MA AISI 316 Stainless Steel, Carbide Solution Treated in Finished Condition
B8M2 AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8M3 AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8P Class 1 AISI 305 Stainless Steel, Carbide Solution Treated
B8P Class 2 AISI 305 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8PA AISI 305 Stainless Steel, Carbide Solution Treated in Finished Condition
B8N AISI 304N Stainless Steel, Carbide Solution Treated
B8N AISI 304N Stainless Steel, Carbide Solution Treated and Strain Hardened
B8MLCuN AISI 304N Stainless Steel, Carbide Solution Treated
B8MLCuN UNS S31254 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8MLCuNA UNS S31254 Stainless Steel, Carbide Solution Treated
B8T Class 1 AISI 321 Stainless Steel, Carbide Solution Treated
B8T Class 2 AISI 321 Stainless Steel, Carbide Solution Treated and Strain Hardened
B8TA AISI 321 Stainless Steel, Carbide Solution Treated in Finished Condition
B8R Nitronic 50/UNS S20910 Stainless Steel, Carbide Solution Treated
B8RA Nitronic 50/UNS S20910 Stainless Steel, Carbide Solution Treated in Finished Condition
B8S Nitronic 60/UNS S21800 Stainless Steel, Carbide Solution Treated
B8SA Nitronic 60/UNS S21800 Stainless Steel, Carbide Solution Treated
B8LN AISI 304LN Stainless Steel, Carbide Solution Treated
B8LNA AISI 304LN Stainless Steel, Carbide Solution Treated in Finished Condition
B8MLN AISI 316LN Stainless Steel, Carbide Solution Treated
B8MLNA AISI 316LN Stainless Steel, Carbide Solution Treated in Finished Condition
B8CLN AISI 347LN Stainless Steel, Carbide Solution Treated
B8CLNA AISI 347LN Stainless Steel, Carbide Solution Treated in Finished Condition

ASTM A194 Grade 8MLN Chemical Components

Grade Material UNS
Number
C, % Mn, % Ph, % S, % Si, % Cr, % Ni, % Mo, % Ti, % Cb & Ta, % N, % Other Elements, %
8MLN Type 316LN S31653 0.030 2.000 0.045 0.030 1.000 16.0-18.0 10.0-13.0 2.0-3.0 - - 0.10-0.16 -

ASTM A194 Grade 8MLN Hardness Requirement

Grade & Type Brinell Hardness Rockwell Hardness
C Scale B Scale

ASTM A194 Grade 8MLN Proof Load (Inch Series)

Nominal Size, inch Threads per inch Stress Area inch Proof Load, lbf
All Types of Grade 8
Heavy Hex Hex
1/4" 20 0.0316 5570 4770
5/16" 18 0.0524 9170 7860
3/8" 16 0.0774 13560 11620
7/16" 14 0.1063 18600 15940
1/2" 13 0.1419 24830 21280
9/16" 12 0.1820 31850 27300
5/8" 11 0.2260 39550 33900
3/4" 10 0.3340 58450 50100
7/8" 9 0.4620 80850 69300
1" 8 0.606 106000 90900
1 1/8" 8 0.7900 138200 118500
1 1/4" 8 1.0000 175000 150000
1 3/8" 8 1.2330 215800 185000
1 1/2" 8 1.492 261100 223800

ASTM A194 Grade 8MLN Marking

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