ASTM A193
This specification covers alloy and stainless steel bolting for pressure vessels, valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications.(Heavy Hex, Studs, Anchor Blots & Jack Screws)

* Optional welding & Counter-Punching/ Tighten Torque(For Anchor Bolts).

  • B7 Alloy steel, AISI 4140/4142 quenched and tempered
  • B7M Alloy steel, AISI 4140/4142 quenched and tempered
  • B8 Class 1 Stainless steel, AISI 304, carbide solution treated.
  • B8M Class 1 Stainless steel, AISI 316, carbide solution treated.
  • B8 Class 2 Stainless steel, AISI 304, carbide solution treated, strain hardened
  • B8M Class 2 Stainless steel, AISI 316, carbide solution treated, strain hardened

A193 MECHANICAL PROPERTIES

Grade Size Tensile Ksi, Min Yield, Ksi, Min Elong, %, Min RA % Min HBW HRC
B7 Up to 2-12″ 125 105 16 50 321 Max 35 Max
2-1/2 – 4″ 115 95 16 50
B7M Up to 4″ 100 80 18 50 B93 B99
B8 Class 1 All 75 30 30 50 223 Max 35 Max
B8M Class 1 All 75 30 30 50 223 Max 96 Max
B8 Class 2 Up to 3/4″ 125 100 12 35 321 Max 35 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 Class 2 Up to 3/4 110 95 15 45 321 Max 35 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

A193 CHEMICAL PROPERTIES

Element B7(AISI 4140) B8(AISI 304) B8M(AISI 316)
Carbon 0.37 – 0.49% 0.08% Max 0.08% Max
Manganese 0.65 – 1.10% 2.00% Max 2.00% Max
Phosphorus, Max 0.035% 0.045% 0.045%
Sulfur, Max 0.040% 0.030% 0.030%
Silicon 0.15 – 0.35% 1.00% Max 1.00% Max
Chromium 0.75 – 1.20% 18.0 – 20.0% 16.0 – 18.0%
Nickel 8.0 – 11.0% 10.0 – 14.0%
Molybdenum 0.15 – 0.25% 2.00 – 3.00%

A193 RECOMMENDED ASSEMBLY COMBINATION

Bolt Grade Nuts Washers
B7 A194 Grade 2h F436
B8 Class 1 A194 Grade 8 SS304
B8M Class 1 A194 Grade 8M SS316
B8 Class 2 A194 Grade 8 SS304
B8M Class 2 A194 Grade 8M SS316