ASTM A193 Grade B8M Class 2 Stud Bolts
Lightning Bolt is an ISO 9001 certified fastener manufacturer for ASTM A193 Grade B8M Class 2 Stud Bolts. In addition to many different sizes and grades of ASTM A193 Grade B8 Stud Bolts, we also carry one of the largest inventories of ASTM A194 Grade 8 & 8M stainless heavy hex nuts in North America. Very commonly used in the assembly of industrial pipe & valves, the chemical composition of ASTM A193 Grade B8M Class 2 Stud Bolts are considered nearly identical to grade 316 stainless steel, hover they are also strain hardened. Email us your inquiries at sales@lightningboltandsupply.com
Many of our customers may understand that ASTM A193/A193M is a specification that covers both inch and metric series carbon alloy steel and stainless steel bolting materials. This includes externally threaded bolts, screws, and studs. It is intended to cover alloy and stainless steel bolting material for pressure vessels, valves, flanges, and fittings for high temperature service. Bars and wire shall be hot-wrought, and the material may be further processed by center less grinding or by cold drawing. Austentic stainless steel, which is a 300 series stainless, has austenite, which is a a metallic, non-magnetic, allotrope of iron as its primary phase. Such alloys contain chromium, nickel (and sometimes nitrogen and molybdenum) & although they can not be thru hardened, they can be carbide solution treated or carbide solution treated & strain-hardened (which is considered “class2”).
Heat treated conditions for the ferritic materials include:
- normalized & tempered
- quenched & tempered.
Heat treated conditions for the austentic stainless steels include:
- Carbide solution treated (Class 1)
- Carbide solution treated after finishing (Class 1A)
- Carbide solution treated nitrogen-bearing stainless steels (Class 1B & 1C)
- Carbide solution treated by cooling rapidly from the rolling temperature (Class 1D)
- Carbide solution treated and Strain-hardened (Classes 2, 2B, and 2C)
All austentic stainless steels shall receive a carbide solution treatment which applies to each class. Class 1, 1B, and 1C (Grades B8R and B8S only), 2, 2B, and 2C can apply to bar, wire, and finished fasteners. Class 1A (ALL GRADES) and Class 1C (GRADES B8RA & B8SA only) can apply to finished fasteners as well. Class 1D applies only to bar and wire and finished fasteners that are machined directly from class 1D bar or wire without any subsequent hot or cold working. Finished products must conform to ASTM Chemical composition and Mechanical Properties tables (listed below).
Class 2 materials shall be carbide solution treated by heating for the ambient temperature and holding at a sufficient time at a temperature at which the chromium carbide will go into solution and then cooling at a rate sufficient to prevent the precipitation of the carbide. Stain-hardening of austentic steels is the increase in strength and hardness that results from plastic deformation below the re crystallization temperature (cold work). This effect is produces in austentic stainless steels by reducing oversized bars or wire to the desired final size by cold drawing or other process. The degree of strain-hardening achievable in any alloy is limited by its strain-hardening characteristics. In addition, the amount of strain-hardening that can be produced is further limited by the variables of the process, such as the total amount of cross section reduction, die angle, and bar size. In large diameter bars, for example, plastic deformation will occur principally in the outer regions of the bar so the the increased strength and hardness due to strain-hardening is achieved predominantly near the surface of the bar. Therefore, the smaller the bar, the greater the penetration of the strain-hardening.
Why Lightning Bolt ASTM A193 Grade B8M Class 2 Stud Bolts?
Lightning Bolt & Supply has been servicing North America’s industrial fastener needs for over 25 years. Since then, our focus on the production of high quality parts at competitive pricing has allowed us to become an industry leader. Our niche in exotic high nickel alloy fasteners include materials such as: hastelloy, Inconel, monel, A-286, 904L, Alloy-20, duplex stainless as well as many additional alloys.
Being centrally headquartered in Baton Rouge, Louisiana, we are capable of shipping to jobsites all over the world. Many of our industrial projects that we supply material to include anchor bolts, and also stud bolts of many different ASTM grades. These include B7, L7, B16, B8, B8M, stain hardened and many more. In addition to being an ISO certified fastener manufacturer, we were awarded “Corporate Supplier of the Year” by WBENC.
ASTM A193 B8M, B8MA, B8M2, B8M3, B8P, B8PA
Identification | B8M, B8MA, B8M2, B8M3 | B8P, B8PA | ||
---|---|---|---|---|
Grade | 18 Chromium- 10 Nickel- 2 Molybdenum (Type 316 Stainless) | Unstabilized 18 Chromium - 8 Nickel (Type 305 Nickel) | ||
Element | Range | Tolerance +/- | Range | Tolerance +/- |
Carbon, max | 0.08 | 0.01 over | 0.12 | 0.01 over |
Manganese, max | 2.00 | 0.04 over | 2.00 | 0.04 over |
Phosphorus, max | 0.045 | 0.010 over | 0.045 | 0.010 over |
Sulfur, max | 0.030 | 0.005 over | 0.030 | 0.005 over |
Silicon | 1.00 | 0.05 over | 1.00 | 0.05 over |
Chromium | 16.00 - 18.00 | 0.20 | 17.00 - 19.00 | .20 |
Nickel | 10.00 - 14.00 | 0.15 | 11.00 - 13.00 | 0.15 |
Molybdenum | 2.00 - 3.00 | 0.10 | - | - |
Columbium + Tantalum |
ASTM A193 TENSILE STRENGTH / HARDNESS CHART
Grade and Class | Diameter | Tensile Strength Min KSI | Yield Strength 0.2% Offset KSI | Elongation in 4D, Min, % | Reduction of Area Min, % | Hardness Max Brinell | Hardness Max Rockwell |
---|---|---|---|---|---|---|---|
B5 | up to 4" incl | 100 | 80 | 16 | 50 | - | - |
B6 | up to 4" incl | 110 | 85 | 15 | 50 | - | - |
B6X | up to 4" incl | 90 | 70 | 16 | 50 | - | C26 |
B7 | to 2-1/2" | 125 | 105 | 16 | 50 | - | C35 |
over 2-1/2 to 4" | 115 | 95 | 16 | 50 | - | C35 | |
over 4" to 7" | 100 | 75 | 18 | 50 | - | C35 | |
B7M | up to 4" incl | 100 | 80 | 18 | 50 | 235 | B99 |
over 4" to 7" | 100 | 75 | 18 | 50 | 235 | B99 | |
B16 | to 2-1/2" | 125 | 105 | 18 | 50 | 321 | C35 |
over 2-1/2" to 4" | 110 | 95 | 17 | 45 | 321 | C35 | |
over 4" to 7" | 100 | 85 | 16 | 45 | 321 | C35 | |
Classes 1 and 1D: B8, B8M, B8P, B8LN, B8ML | ALL | 75 | 30 | 30 | 50 | 223 | B96 |
Class 1: B8C, B8T | ALL | 75 | 30 | 30 | 50 | 223 | B96 |
Class 1A: B8A, B8CA, B8MA, B8PA, B8TA, B8LNA, B8MLNA, B8NA, B8MNA, B8MLCuNA | ALL | 75 | 30 | 30 | 50 | 192 | B90 |
Classes 1B & 1D: B8N, B8MN, B8MLCuN | ALL | 80 | 35 | 30 | 40 | 223 | B96 |
Class 1C and 1D: B8R | ALL | 100 | 55 | 35 | 55 | 271 | C28 |
Class 1C: B8RA | ALL | 100 | 55 | 35 | 55 | 271 | C28 |
Classes 1C and 1D: B8S | ALL | 95 | 50 | 35 | 55 | 271 | C28 |
Classes 1C: B8SA | ALL | 95 | 50 | 35 | 55 | 271 | C28 |
Class 2: B8, B8C, B8P, B8T, B8N | to 3/4" | 125 | 100 | 12 | 35 | 321 | C35 |
over 3/4" to 1" | 115 | 80 | 15 | 35 | 321 | C35 | |
over 1" to 1-1/4" | 105 | 65 | 20 | 45 | 321 | C35 | |
over 1-1/4 to 1-1/2" incl | 100 | 50 | 28 | 45 | 321 | C35 | |
Class 2 B8M, B8MN, B8MLCuN | to 3/4" | 110 | 96 | 15 | 45 | 321 | C35 |
over 3/4" to 1" | 100 | 80 | 20 | 45 | 321 | C35 | |
over 1" to 1-1/4" | 95 | 65 | 25 | 45 | 321 | C35 | |
over 1-1/4 to 1-1/2" incl | 90 | 50 | 30 | 45 | 321 | C35 | |
Class 2B: B8, B8M2 | to 2" incl | 95 | 75 | 25 | 40 | 321 | C35 |
over 2" to 2-1/2" incl | 90 | 65 | 30 | 40 | 321 | C35 | |
over 2-1/2 " to 3" incl | 80 | 55 | 30 | 40 | 321 | C35 | |
Class 2C: B8M3 | to 2" incl | 85 | 65 | 30 | 60 | 321 | C35 |
over2" | 85 | 60 | 30 | 60 | 321 | C35 |