banner
img
img

ASTM 193

The specification of ASTM A193 includes high tensile fasteners, which are composed of stainless steel or alloy. These are primarily used in the applications of chemical and petroleum construction. The chief use of these bolting solutions is in services related to high pressure and temperatures like valves, fittings and flanges, and pressure valves.

Let us now check out the grades that fall in the A193 segment.

A193 Grades

B7 Alloy steel, AISI 4140/4142 quenched and tempered
B7M Alloy steel, AISI 4140/4142 quenched and tempered
B8 Stainless steel, AISI 304, carbide solution treated.
B8 Class 2 Stainless steel, AISI 304, carbide solution treated, strain hardened
B8M Stainless steel, AISI 316, carbide solution treated.
B8M Class 2 Stainless steel, AISI 316, carbide solution treated, strain hardened
B16 Alloy steel, AISI 4340 quenched and tempered

A193 Mechanical properties

Grade Size Tensile ksi, min Yield ksi, min Elong %, min RA % min HBW Rockwell
B7 Up to 2-1/2 125 105 16 50 321 Max 35 HRC max
2-5/8 - 4 115 95 16 50
4-1/8 - 7 100 75 18 50
B7M Up to 4 100 80 18 50 235 Max -
Over 4 - 7 100 75 18 50
B8 All 75 30 30 50 223 Max 96 HRB max
B8 Class 2 Up to 3/4 125 100 12 35 321 Max 35 HRC max
7/8 - 1 115 80 15 35
1-1/8 - 1-1/4 105 65 20 35
1-3/8 - 1-1/2 100 50 28 45
B8M All 75 30 30 50 223 Max 96 HRB max
B8M Class 2 Up to 3/4 110 95 15 45 321 Max 35 HRC max
7/8 - 1 100 80 20 45
1-1/8 - 1-1/4 95 65 25 45
1-3/8 - 1-1/2 90 50 30 45
B16 Up to 2-1/2 125 105 18 50 321 Max 35 HRC max
Over 2-1/2 to 4 110 95 17 45
Over 4 to 8 100 85 16 45

A193 Chemical properties

Element B7 (AISI 4140) B8 (AISI 304) B8M (AISI 316) B16
Carbon 0.37 - 0.49% 0.08% max 0.08% max 0.36 - 0.47%
Manganese 0.65 - 1.00% 2.00% max 2.00% max 0.45 - 0.70&
Phosphorus, max 0.035% max 0.045% max 0.045% max 0.035% max
Sulfur, max 0.040% max 0.030% max 0.030% max 0.040% max
Silicon 0.15 - 0.35% 1.00% max 1.00% max 0.15 - 0.35%
Chromium 0.80 - 1.10% 18.0 - 20.0% 16.0 - 18.0% 0.80 - 1.15
Nickel - 8.0 - 11.0% 10.0 - 14.0% -
Molybdenum 0.15 - 0.25% - 2.00 - 3.00% 0.50 - 0.65

A193 compatible hardware

Bolt Grade Nut Washers
B7 A194 Grade 2H F436
B7M A194 Grade 2HM F436
B8 A194 Grade 8 SS304
B8 Class 2 A194 Grade 8 SS304
B8M A194 Grade 8M SS316
B8M Class 2 A194 Grade 8M SS316
B16 A194 Grade 16 F436