China Hot Rolled and Cold Drawn Steel Round Bar Suppliers - High Quality from Trusted Factory
Specification
| Parameter | Range / Options |
| Diameter | 6 mm – 500 mm (1/4" – 24") |
| Length | 3 m – 12 m (standard: 6 m) |
| Tolerance Standards | EN 10277, ASTM A29, JIS G3124 |
Material Standard
| Material Type | Standard | Common Grades |
| Carbon Steel | ASTM A36 / A29 | A36, 1018, 1045, 1215 |
| EN 10083 / 10025 | S235JR, S355JR, C45 | |
| JIS G3101 / G4051 | SS400, S45C, SCM435 | |
| Stainless Steel | ASTM A276 / A484 | 304/L, 316/L, 303, 310S, 630 (17-4PH) |
| EN 10088 | 1.4301, 1.4401, 1.4305 | |
| Alloy Steel | ASTM A29 | 4140, 4340, 8620 |
| EN 10084 | 16MnCr5, 20MnCr5 | |
| Tool Steel | ASTM A681 | O1, D2, A2, M2 |
| Aluminum | ASTM B221 | 6061, 6063, 7075, 2024 |
| Brass / Bronze | ASTM B16 / B124 | C36000, C46400 |
Manufacturing Methods
Steel is heated above recrystallization temperature (approximately 1200°C) and passed through rolling mills. This process produces bars with lower dimensional accuracy and a scaled surface, but offers cost-effectiveness suitable for construction and general applications where finish is not critical.
Hot-rolled bars are pulled through dies at room temperature, resulting in superior surface finish, tighter dimensional tolerances, and increased strength. These bars are ideal for precision components and machined parts.
The surface layer is removed by cutting to achieve high dimensional accuracy, a glossy finish, and defect-free surface condition.
Bars are ground to precise diameter tolerances, providing extreme precision, excellent straightness, and a polished surface for demanding applications.
Common for aluminum and copper, where billets are forced through a die opening to produce long lengths with consistent cross-sections.
Applications
Round bars are extensively used to manufacture shafts, gears, spindles, rollers, pins, and bushings. Their cylindrical shape makes them ideal for rotating parts and components requiring symmetry.
Essential for producing axles, drive shafts, steering components, piston rods, and fasteners. High-strength alloy grades are specified for critical drivetrain applications.
Used as reinforcing bars, column supports, braces, and anchors. Hot-rolled round bars provide reliable strength for structural frameworks.
Employed in downhole tools, valve components, pump shafts, and wellhead equipment. Corrosion-resistant stainless and alloy grades perform in harsh environments.
Precision-ground bars serve in landing gear components, turbine shafts, structural connectors, and fasteners where strict tolerances and high reliability are required.
Raw material for CNC machining, turned parts, bolts, studs, and custom components across all industries.
Stainless steel and naval brass round bars provide corrosion resistance for hardware, fittings, shafts, and structural elements in marine environments.
Used in turbine components, generator shafts, and nuclear reactor internals, often in specialized high-temperature alloys.
Stainless steel round bars are specified for surgical instruments, implants, and medical device components requiring biocompatibility and cleanability.
Sanitary-grade stainless steel bars serve in equipment frames, conveyor components, and processing machinery where hygiene is critical.
Frequently Asked Questions
Round bars are available in diameters ranging from 6 mm to 500 mm (1/4" to 24"), with standard lengths from 3 m to 12 m. The most commonly stocked length is 6 m.
Hot-rolled bars are produced at high temperatures (~1200°C), offering cost efficiency but lower dimensional accuracy and a scaled surface. Cold-drawn bars are processed at room temperature through dies, resulting in tighter tolerances, improved surface finish, and higher strength — making them better suited for precision machining applications.
For corrosion-resistant applications, stainless steel grades such as 304/L, 316/L, or 310S are recommended. Grade 316/L offers superior resistance in chloride-rich environments such as marine or chemical processing. For highly demanding conditions, duplex or 17-4PH grades may be specified.
Round bars are manufactured to internationally recognized tolerance standards including EN 10277 (European), ASTM A29 (American), and JIS G3124 (Japanese). The applicable standard depends on the end-use region and customer specification requirements.
Yes. Cold-drawn, peeled, and centerless-ground round bars are particularly well-suited for CNC machining due to their tight dimensional tolerances and clean surface condition. Free-machining grades such as 1215 (carbon steel) and 303 (stainless steel) are specifically designed to improve machinability and reduce tool wear.
Yes. In addition to steel, round bars are available in aluminum alloys (6061, 6063, 7075, 2024 per ASTM B221), brass (C36000), and bronze (C46400 per ASTM B16/B124). Aluminum bars are commonly produced via extrusion and are widely used in aerospace, automotive, and lightweight structural applications.