
Steel bars and rods are essential materials in various industries, particularly construction and manufacturing. They come in different shapes, sizes, and grades, each suited for specific applications.
What is a steel bar?
A steel bar is a solid piece of steel that is manufactured in various shapes, sizes, and grades to serve multiple purposes across various industries. These bars are typically produced through processes like hot rolling, cold rolling, forging, or extrusion.
Types of steel bars

Round Bars:
- Cylindrical shape.
- Used in machining, construction, and manufacturing components like shafts and rods.
Square Bars:
- Square cross-section.
- Commonly used in construction, for making frames, and as base material for various machined components.
Flat Bars:
- Rectangular cross-section with flat surfaces.
- Used in fabrication, construction, and for making brackets, bases, and other structural components.
Hexagonal Bars:
- Hexagonal cross-section.
- Often used in the fastener industry to make nuts, bolts, and other hardware.
Deformed/Rebar:
- Typically used in concrete reinforcement.
- Features surface deformations (ribs) for better bonding with concrete.
Commons uses of steel bars
- Construction: Used as reinforcement bars (rebars) in concrete structures, frameworks for buildings, bridges, and other infrastructure projects.
- Manufacturing: Utilized in making machinery parts, automotive components, tools, and equipment.
- Industrial: Employed in the production of heavy equipment, mining machinery, and industrial structures.
- Agriculture: Used in the manufacture of agricultural tools and machinery.
- Domestic and Commercial: Applied in furniture making, decorative items, and other household and commercial products.
Manufacture Technique
The manufacture of steel bars can be achieved through various techniques, two of the most common being hot rolling and cold drawing. Each method has its own set of processes and results in steel bars with different properties suitable for specific applications.

Hot Rolling
Hot rolling is a process where steel is heated above its recrystallization temperature and then rolled into shape. Here’s an overview of the hot rolling process:
- Heating: Steel billets or slabs are heated in a furnace to a temperature typically above 1100°C (2000°F).
- Rolling: The heated steel is passed through a series of rolling mills, where it is progressively reduced in thickness and shaped into the desired form (round, square, flat, etc.).
- Finishing: The rolled steel is cut to the required length and allowed to cool. During cooling, it may undergo further processing such as straightening or cutting.
- Cooling: The bars are cooled naturally or with water sprays to achieve the desired mechanical properties.
- Inspection and Packaging: The final product is inspected for quality and defects, and then packaged for shipment.
Properties and Applications:
- Properties: Hot-rolled steel bars have a rough surface finish, less precise dimensions, but good ductility and toughness.
- Applications: Commonly used in construction (rebar, structural beams), automotive frames, and machinery parts.

Cold Drawing
Cold drawing is a process where steel is drawn through a die without heating it above its recrystallization temperature. This results in a product with a smoother finish and more precise dimensions. The cold drawing process typically involves the following steps:
- Pickling: The hot-rolled steel bar is cleaned in an acid bath to remove scale and impurities.
- Pointing: One end of the bar is tapered to a point to facilitate entry into the drawing die.
- Drawing: The bar is pulled (drawn) through a series of dies to reduce its diameter and improve its surface finish and mechanical properties. This process may be repeated several times with intermediate annealing (heating) to relieve internal stresses.
- Annealing: The drawn bars may be heat-treated to improve ductility and relieve internal stresses.
- Finishing: The cold-drawn bars are straightened, cut to length, and may undergo additional surface treatments.
- Inspection and Packaging: The final product is inspected for quality and defects, then packaged for shipment.
Properties and Applications:
- Properties: Cold-drawn steel bars have a smooth surface finish, closer dimensional tolerances, and higher tensile strength due to work hardening.
- Applications: Used in precision machining, automotive components, tools, fasteners, and other applications where high dimensional accuracy and surface finish are crucial.
Standards and Materials

Forged Pipe Fittings Material Grade
Nickel Alloy | ASTM/ASME SB 425 | Alloy 825/Incoloy 825/UNS N08825 |
ASTM/ASME SB 446 | Alloy 625/UNS N06625 | |
ASTM/ASME SB164 | Monel 400/Alloy 400/UNS N04400 | |
ASTM/ASME SB 408 | Alloy 800HT/Incoloy 800HT/UNS N08811, Alloy 800/Incoloy 800/UNS N08800, Alloy 800H/Incoloy 800H/UNS N08810 | |
ASTM/ASME SB 649 | Alloy 925/Incoloy 925/UNS N09925, Alloy 926/Incoloy 926/UNS N08926, Alloy 31/UNS N08031 | |
ASTM/ASME SB 166 | Alloy 600/Inconel 600/UNS N06600,Alloy 601/Inconel 601/UNS N06601 | |
ASTM/ASME SB160 | Alloy 200/UNS N02200, Alloy 201/UNS N02201 | |
ASTM/ASME SB 472 | Hastelloy C276/UNS N10276,Alloy 926/Incoloy 926/UNS N08926,Alloy 31/UNS N08031,Alloy 20/N08020,Alloy C-22/Hastelloy C22/N06022, Alloy 600/Inconel 600/UNS N06600, | |
ASTM/ASME SB 473 | Alloy 20/UNS N08020 | |
ASTM/ASME SB 574 | Hastelloy C-276/UNS N10276 | |
ASTM/ASME SB 637 | Alloy 718/Inconel 718/N07718 | |
Stainless Steel | ASTM/ASME SA 276 /479 | 304/SUS304/UNS S30400, 304L/UNS S30403, 316/UNS S31600, 316Ti/UNS S31635, 316H/UNS S31609, 316L/UNS S31603, 310S/UNS S31008, 321/UNS S32100, 321H/UNS S32109, 347/UNS S34700, 347H/UNS S34709, F51/S31803/2205, F53/S32750/2507, F55/S32760, F44/S31254/254SMO, S31050/1.4466, F904L/N08904,Alloy 800HT/Incoloy 800HT/UNS N08811, Alloy 800/Incoloy 800/UNS N08800, Alloy 800H/Incoloy 800H/UNS N08810 |
ASTM/ASME SA 479 | 304H/UNS S30409 | |
Carbon Steel and Low Alloy Steel | ASTM/ASME SA 694 | F42, F46, F48, F50, F52, F56, F60, F65, F70 |
ASTM/ASME SA 350 | LF2, LF3 | |
ASTM A105/ASME SA105 |
Conclusion
In summary, a steel bar is a fundamental material in numerous applications due to its strength, versatility, and durability. It is essential in both construction and manufacturing, playing a crucial role in the development and maintenance of infrastructure and machinery.
FAQs
- Hot-Rolled Steel Bars: Made by heating steel above its recrystallization temperature and rolling it into shape. They have a rough surface, lower dimensional accuracy, but good ductility and toughness.
- Cold-Drawn Steel Bars: Made by drawing steel through a die at room temperature. They have a smooth surface, high dimensional accuracy, and higher tensile strength due to work hardening.
When choosing a steel bar, consider the following factors:
- Application Requirements: Select the type of steel bar based on the specific needs of your project or product.
- Mechanical Properties: Choose based on required strength, toughness, and ductility.
- Environmental Factors: Consider corrosion resistance and weathering, especially for outdoor or harsh environments.
- Standards and Specifications: Ensure the material meets relevant industry standards such as ASTM, AISI, ISO, etc.
Common standards and specifications for steel bars include:
- ASTM (American Society for Testing and Materials): e.g., ASTM A615 (standard for rebar).
- AISI (American Iron and Steel Institute): e.g., AISI 304, 316 (standards for stainless steel).
- ISO (International Organization for Standardization): e.g., ISO 6935 (standard for steel bars for concrete reinforcement).
- GB (Guobiao, Chinese National Standards): e.g., GB 1499 (standard for rebar).
The corrosion resistance of steel bars depends on their material and surface treatment. Stainless steel bars have high corrosion resistance, suitable for humid or corrosive environments. Other types of steel bars can be coated or galvanized to enhance corrosion resistance.
When storing and handling steel bars, consider the following:
- Prevent Corrosion: Store steel bars in a dry place, away from water and corrosive substances.
- Avoid Deformation: Ensure even support during storage to prevent bending or deformation.
- Safety: Use appropriate equipment and tools for handling to ensure the safety of workers.
STEEL BARS AND RODS SSM can provide
Types | Round Bar Square Bar Hexagon Bar Flat Bar | ||
Size | Diameter | 5 – 500mm | |
Length | ≤12M or As Per Client’s Requirements. | ||
Diameter Tolerance | H7 H9 H10 H11 | ||
Surface | Black Bright Pickling white | ||
Manufacture Technique | Hot Rolling, Cold-drawing | ||
Standard | SUS AISI DIN |
At our company, we specialize in the production of various types of bars including Round Bar, Square Bar, Hexagon Bar, and Flat Bar, with diameters ranging from 5mm to 500mm. Our products adhere to industry standards such as SUS, AISI, and DIN, ensuring high quality and precision.
We offer a wide range of materials to meet diverse needs, including Nickel Alloy, Stainless Steel, Carbon Steel, and Low Alloy Steel. Whether you require materials for industrial applications or specialized projects, we have the expertise and capability to deliver according to your specifications.
With our commitment to quality and customer satisfaction, we aim to be your preferred supplier for all your bar requirements. Contact us today to discuss how we can meet your specific needs and provide tailored solutions to support your projects.