Cold heading Service


A193 B8 stud bolts are a type of fastener used in various industries, particularly in applications where high-temperature and high-pressure conditions are present. The “A193” refers to the ASTM A193 specification, which covers alloy steel and stainless steel bolting materials for high-temperature or high-pressure service. The “B8” specifically refers to a particular grade within the A193 specification.

A193 B8 stud bolts are made from stainless steel grade 304, which is an austenitic chromium-nickel alloy known for its corrosion resistance and good mechanical properties. These stud bolts are commonly used in applications where resistance to corrosion and elevated temperatures is required, such as in chemical, petrochemical, and power generation industries.

These stud bolts are threaded rods with threads on both ends, and they are commonly used in conjunction with two nuts to create a secure joint in various assemblies. They play a crucial role in maintaining the integrity of structures and equipment under demanding conditions.

Specification of A193 B8 stud bolts:

A193 B8 stud bolts, made from stainless steel grade 304, find applications in various industries due to their corrosion resistance and mechanical properties. Here are some common applications:

Product nameASTM A193 B8 Stud Bolts
Diameter1/4″ – 4″
Dimension StandardASME B18.31.2
MaterialStainless steel, AISI 304
Compatible nuts/washersA194 GR.8 heavy hex nuts
Manufacturing Processwire drawing, thread rolling, heat treatment, surface treatment
Surface treatmentBlack Oxide Coating/Zinc Plating (Electroplating)/Hot-Dip Galvanizing/Mechanical Galvanizing/Dacromet Coating/Painting or Powder Coating
Application IndustryPiping Systems/Pressure Vessels/Pressure Vessels/Oil and Gas Industry/Power Generation/Chemical Processing

It’s important to note that A193 B8 stud bolts are not suitable for all applications. Depending on the specific requirements of a project, other grades of stud bolts may be more appropriate.

Chemical Composition:

ElementsRangeAllowed Variation, %
Carbon, max0.08 %+ 0.01
Manganese, max2.00 %+ 0.04
Phosphorus, max0.045 %+ 0.010
Sulfur, max0.030 %+ 0.005
Silicon, max1.00 %+ 0.05
Chromium18.0 - 20.0%+/- 0.20
Nickel8.0 - 11.0%+/- 0.15
Molybdenum+/- 0.10

 Mechanical and physical properties:

Mechanical Requirements, Inch Products
ClassDiameterTensile Strength, min, ksiYield Strength, min, ksiElongation in 4D min, %Reduction of Area, min, %Hardness, max
1All Diameters75303050223 HBW96 HRB
2Up to 3/41251001235321 max35 HRC max
7/8 - 1115801535
1-1/8 - 1-1/4105652035
1-3/8 - 1-1/2100502845

Quality control of A193 B8 Stud bolts:

Control MethodDetail
Material Inspection:Verify the material's composition, heat treatment, and quality upon receipt. Conduct metallurgical analysis to ensure the material properties meet the standards.
Process Control:Implement strict process control measures for heat treatment, machining, threading, and any other manufacturing steps. Maintain consistent process parameters to ensure uniform quality.
Inspection Points:Introduce inspection points at various stages of manufacturing to check for defects, dimensions, and quality. Inspect threading, dimensions, surface finish, and other critical parameters.
Sampling and Testing:Regularly sample products for testing, such as tensile testing, hardness testing, and metallurgical analysis, to ensure they meet the required specifications.
Thread Inspection:Thoroughly inspect threading using proper thread gauges to ensure accurate dimensions and fit with mating components.
Traceability:Implement a traceability system to track each fasteners journey from raw material to final product. This aids in accountability and recalls if necessary.