Views: 0 Author: Site Editor Publish Time: 2025-04-11 Origin: Site
On March 18, 2025, an old customer of our company sent us an inquiry for ASTM A193 Grade B8 Class 2 Stud Bolts, and each bolt was equipped with two hexagonal nuts and two washers. After the quotation was completed, the customer communicated the product details to us, and a week later, the customer placed an order with us.
ZIZI is a company specializing in the production and processing of pipes and fittings. The pipes and pipe fittings we produce are mainly used in chemical, petroleum, natural gas, water conservancy, electric power, marine engineering and other fields. The products mainly include seamless pipes, welded pipes, butt-welded pipe fittings, high-pressure forged pipe fittings and flanges of various sizes. The materials include carbon steel, stainless steel, alloy steel, low-temperature steel, duplex steel, base alloy, etc.
ITEM | DESCRIPTION | QUANTITY | UNIT |
1 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M20 x 210mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 264 | SET |
2 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M16 x 240mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 968 | SET |
3 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M16 x 170mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 1368 | SET |
4 | STUD BOLT & 2 NUTS W/2 WASHERS WIth ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M20 x 115mm | 96 | SET |
5 | STUD BOLT & 2 NUTS W/2 WASHERS With ASTM A 193-B8 CI2/A 194-8 CI2/ SS304M16x100mmASME B18.2.1 & B18.2.2 | 1158 | SET |
6 | STUD BOLT & 2 NUTS W/2 WASHERS Wit ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M16 x 200mmASME B18.2.1 & B18.2.2 | 222 | SET |
7 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M20 x 210mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 468 | SET |
8 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M16 x 240mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 448 | SET |
9 | STUD BOLT. NUTS W/ 2 WASHERS WI ASTM A 193-B8 CI2/A 194-8 CI2/ SS304 M16 x 170mm ORIGINAL MTC : EN10204 3.1 MUST BE PORVIDED WITH MATERIAL | 848 | SET |
10 | STUD BOLT & 2 NUTS W/ 2 WASHERS with ASTM A 193-B8 CI2/ A 194-812/ SS304 M16x100mm ASME B18.2.1 & B18.2.2 | 792 | SET |
1. Visual Inspection
Check for surface defects, cracks, burrs, pitting, or corrosion.
Ensure uniform thread profile, chamfering, and overall appearance.
2. Dimensional Inspection
Verify diameter, length, thread pitch, and tolerances using calipers, gauges, and micrometers.
Ensure threads comply with ASME B1.1 (Unified Inch) or ISO metric standards.
Class | Marking |
Class 1 | "BPF" Manufacturer's Logo & "B8" Grade Marking |
Class 2 | "BPF" Manufacturer's Logo & "B8SH" Grade Marking |
Class 2B | "BPF" Manufacturer's Logo & "B9" Grade Marking |
ASTM A193 Grade B8 Class 2 Stud Bolts are high-strength stainless steel fasteners designed for high temperature and high-pressure applications, commonly used in pressure vessels, flanges, valves, and pipeline systems in the petrochemical, oil & gas, and power generation industries.
Standard Specification Of | ASTM A193 Grade B8 Stud Bolts |
Type Of Head | Hex, Threading, Square, Round |
Size Type | Inches 3/8 to 3 |
Surface Finish | Plain / Zinc plated / Hot dip galvanized |
Standard Dimensions Of | ASME B18.2.1 |
ASTM A193
A standard specification from ASTM International for alloy and stainless steel bolts, studs, and other externally threaded fasteners.
Mainly used for bolting materials in high-temperature or high-pressure service.
Grade B8
Made from AISI 304 stainless steel (similar to SS304).
Has good corrosion resistance, especially in mild environments.
B8 bolts are widely used in non-sour and moderately corrosive environments.
Class 2
Indicates the bolt has been strain hardened (cold worked) for higher strength compared to Class 1.
Class 2 bolts are stronger than Class 1, but still maintain corrosion resistance.
Identification | B8, B8A | B8C, B8CA |
Grade | Unstabilized 18 chromium - 8 Nickel (Type 304 Stainless) | Stabilized 18 Chromium- 8 Nickel (Type 347 Stainless) |
Element | Range | Range |
Carbon, max | 0.08 | 0.08 |
Manganese, max | 2 | 2 |
Phosphorus, max | 0.045 | 0.045 |
Sulfur, max | 0.03 | 0.03 |
Silicon | 1 | 1 |
Chromium | 18.00 - 20.00 | 17.00 - 19.00 |
Nickel | 8.00 - 11.00 | 9.00 - 12.00 |
Columbium + Tantalum | - | 10x carbon, min |
Mechanical Requirements, Inch Products | |||||||
Class | Diameter | Tensile Strength, min, ksi | Yield Strength, min, ksi | Elongation in 4D min, % | Reduction of Area, min, % | Hardness, max | |
2 | 3/4 and under | 125 | 100 | 12 | 35 | 321 HBW | 35 HRC |
Over ¾ to 1, incl. | 115 | 80 | 15 | 35 | |||
Over 1 to 1-1/4, incl. | 105 | 65 | 20 | 35 | |||
Over 1-1/4 to 1-1/2, incl. | 100 | 50 | 28 | 45 | |||
Mechanical Requirements, Metric Products | |||||||
Class | Diameter | Tensile Strength, min, ksi | Yield Strength, min, ksi | Elongation in 4D min, % | Reduction of Area, min, % | Hardness, max | |
2 | M20 and under | 860 | 690 | 12 | 35 | 321 HBW | 35 HRC |
Over M20 to M24, incl. | 795 | 550 | 15 | 35 | |||
Over M24 to M30, incl. | 725 | 450 | 20 | 35 | |||
Over M30 to M36, incl. | 690 | 345 | 28 | 45 | |||
**All measurements in millimeters** | ||||||||
NOMINAL SIZE (D) | BODY DIAMETER | HEAD THICKNEASTM A193 | ACROASTM A193 THE FLATS | ACROASTM A193 CORNERS | ||||
D (MAX) | D (MIN) | H (MAX) | H (MIN) | F (MAX) | F (MIN) | C (MAX) | C (MIN) | |
m10 | 10 | 9.78 | 6.63 | 6.17 | 17 | 15.73 | 18.48 | 17.77 |
m12 | 12 | 11.73 | 7.76 | 4.24 | 19 | 17.73 | 20.78 | 20.03 |
m14 | 14 | 13.73 | 9.09 | 8.51 | 22 | 20.67 | 24.25 | 23.35 |
m16 | 16 | 15.73 | 10.32 | 9.68 | 24 | 23.67 | 27.71 | 26.75 |
m20 | 20 | 19.67 | 12.88 | 12.12 | 30 | 29.16 | 34.64 | 32.95 |
m24 | 24 | 23.67 | 15.44 | 14.56 | 36 | 35 | 41.57 | 39.55 |
m30 | 30 | 29.67 | 19.48 | 17.92 | 46 | 45 | 53.12 | 50.85 |
m36 | 36 | 35.61 | 23.38 | 21.63 | 55 | 53.8 | 63.51 | 60.79 |
m42 | 42 | 41.38 | 26.97 | 25.03 | 65 | 62.9 | 75.06 | 71.71 |
m48 | 48 | 47.38 | 31.07 | 28.93 | 75 | 72.6 | 86.6 | 82.76 |
m56 | 56 | 55.26 | 36.2 | 33.8 | 85 | 82.2 | 98.15 | 93.71 |
m64 | 64 | 63.26 | 41.32 | 38.68 | 95 | 91.8 | 109.7 | 104.65 |
m72 | 72 | 71.26 | 46.45 | 43.55 | 105 | 101.4 | 121.24 | 115.6 |
m80 | 80 | 79.26 | 51.58 | 48.42 | 115 | 111 | 132.72 | 126.54 |
m90 | 90 | 89.13 | 57.74 | 54.26 | 130 | 125.5 | 150.11 | 143.07 |
m100 | 90 | 99.13 | 63.9 | 60.1 | 145 | 140 | 167.43 | 159.6 |
Flanged joints in pipelines and pressure vessels
Steam systems and boiler equipment
Chemical and petrochemical process systems
Offshore platforms and marine environments
Food & beverage and pharmaceutical industries (non-toxic, corrosion-resistant)
