B8, B8M, B6, B7, Half / Full Thread Bolt, Double Ended Nut, Fasteners, Mumbai, India
 
 

B8 / B8M / B6 / B7 ( Half / Full Thread, Double Ended )

 
Standard : DIN 938, DIN 939, DIN 975, DIN 976, DIN 2509
Thread type : MM, BSW, BSF, UN, UNC, UNF & FINE PITCH
Size in length : Manufactured as per customer requirements.
Threading : UNC / BSW/ BSF. Any size and any length in metric or inches.
B6 Bolt and Nuts
 
Material Grades:

• A2 ( AISI 304 / AISI 304L ) / 1.4301 / 1.4306 / ASTM A193 B8 Cl.1 & Cl.2 /ASTM A320 B8 Cl.1 & Cl.2 / A2-50 / A2-70 / A2-80.
• A4 ( AISI 316 / AISI 316L ) / 1.4401 / 1.4404 / ASTM A193 B8M Cl.1 & Cl.2 / ASTM A320 B8M Cl.1 & Cl.2 / A4-50 / A4-70 / A4-80.
• Stainless Steel "BS 1449" Grades 316S31 & 316S33
• AISI 410 / 1.4006 / ASTM A193 B6.
• ASTM A193 B7. • ASTM A194

 
Scope
This specification is heavily utilized in petroleum and chemical construction applications. The ASTM standard covers alloy steel and stainless steel bolting materials for high temperature or high pressure service. This specification includes fasteners intended for use in pressure vessels, valves, flanges, and fittings. Although, this material is often available in national coarse (UNC) thread pitches, if being used in traditional applications, threads are specified 8 threads per inch (tpi) for diameters above one inch. Further, the same can be produced bearing threads BSW, BSF, fine pitch.
 
Below is a basic summary of a few of the common grades. ASTM A193 covers a number of other standard specifications.
 
A193 Grades
B7 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
B7 Up to 2-1/2 125 105 16 50
2-5/8 - 4 115 95 16 50
4-1/8 - 7 100 75 18 50
B8 Class 1 All 75 30 30 50
B8M Class 1 All 75 30 30 50
B8 Class 2 Up to 3/4 125 100 12 35
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
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 Hardware
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
 
B8 Bolt and Nuts | B8M Bolt and Nuts | B7 Bolt and Nuts | B6 Bolt and Nuts | B8 / B8M / B6 / B7 (Half/Full Thread, Double Ended)
 
 
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