- Keywords: Steel Roud Bar, Carbon Steel Round Bar, Stainless Steel Round Bar, Alloy Steel Round Bar
- Standard: GB/T 702, ASTM A29/A108, EN 10060, JIS G3191, DIN 1013
- Grade: Q235, Q345, 20#/45# (Carbon Steel), 40Cr, 20CrMnTi, 42CrMo (Alloy Steel), A36, 1045, 4140, S45C, C45
- Diameter Range: 5mm-500mm (larger sizes available upon request)
- Length：4m- 12m, or as required
- Delivery Condition: U / N / A / S / FP / AC / QT / EFS
Product Description of Steel Round Bar
Steel Round Bar is a high-quality cylindrical structural steel product with a smooth, uniform cross-section, manufactured from premium steel materials through precision rolling and strict quality control. It is widely recognized for its excellent mechanical properties, high strength, good ductility, and easy processing, making it an indispensable component in various industrial, construction, and manufacturing fields.
Types of Steel Roud Bar:
Type | Key Feature | Common Grade | Typical Use |
Low Carbon | Ductile, weldable | 1018, Q235 | Construction, bolts |
Medium Carbon | Good strength | 1045, 45# | Shafts, gears |
High Carbon | Hard, wear-resistant | 1095, 60# | Springs, tools |
Alloy | High strength | 4140, 40Cr | Aerospace, machinery |
Stainless | Corrosion-resistant | 304, 316 | Food, medical, marine |
Tool Steel | Ultra-hard | H13, D2 | Dies, cutting tools |
Key Features of Steel Roud Bar
1)High strength and durability
2)Good machinability and weldability
3)Uniform chemical composition and mechanical properties
4)Available in various grades for different applications
5)Custom lengths and diameters available
Applications of Steel Round Bar
Manufacturing – shafts, axles, gears, bolts, fasteners
Construction – reinforcement bars, anchor bolts, structural supports
Machinery – machine tool parts, hydraulic cylinders, piston rods
Automotive – transmission shafts, steering components
Shipbuilding – rudder stocks, propeller shafts
Oil & Gas – drill pipes, valve stems
Standard of Steel Round Bar:
Material | Application | ASTM | JIS | GB | Material Grade Cross-Reference |
Stainless Steel Round Bar, 304 Grade | Food processing equipment, medical devices, chemical tanks, pharmaceutical machinery | ASTM A276 | JIS G4303 SUS304 | GB/T 1220 06Cr19Ni10 | 304 (ASTM) = SUS304 (JIS) = 06Cr19Ni10 (GB) |
Stainless Steel Round Bar, 316L Grade | Marine components, offshore oil platforms, biopsy instruments, seawater systems | ASTM A276 | JIS G4303 SUS316L | GB/T 1220 022Cr17Ni12Mo2 | 316L (ASTM) = SUS316L (JIS) = 022Cr17Ni12Mo2 (GB) |
Carbon Steel Round Bar, 45# | Shafts, gears, connecting rods, crankshafts, machine tool spindles | ASTM A510 / A29 | JIS G4051 S45C | GB/T 699 45# | 45# (GB) = S45C (JIS) = 1045 (ASTM) |
Carbon Steel Round Bar, 20# | Bolts, pins, low-stress structural parts, automotive brackets | ASTM A510 / A29 | JIS G4051 S20C | GB/T 699 20# | 20# (GB) = S20C (JIS) = 1020 (ASTM) |
Alloy Steel Round Bar, 4140 Grade | High-strength axles, drill collars, hydraulic rods, firearm components | ASTM A29 | JIS G4105 SCM440 | GB/T 3077 42CrMo | 4140 (ASTM) = SCM440 (JIS) = 42CrMo (GB) |
Alloy Steel Round Bar, 40CrNiMoA | Aircraft landing gear, heavy-duty gears, high-torque shafts | ASTM A29 | JIS G4105 SNCM8 | GB/T 3077 40CrNiMoA | 40CrNiMoA (GB) = SNCM8 (JIS) = 4340 (ASTM) |
Tool Steel Round Bar, SKD61 | Die casting molds, hot forging dies, plastic injection molds | ASTM A681 | JIS G4404 SKD61 | GB/T 1299 4Cr5MoSiV1 | SKD61 (JIS) = H13 (ASTM) = 4Cr5MoSiV1 (GB) |
Copper Round Bar, C11000 | Electrical busbars, grounding rods, switchgear contacts | ASTM B170 | JIS H3100 C1100 | GB/T 5231 T2 | C11000 (ASTM) = C1100 (JIS) = T2 (GB) |
Aluminum Round Bar, 6061-T6 | Aircraft fittings, marine hardware, bicycle frames, structural supports | ASTM B221 | JIS H4000 A6061 | GB/T 3190 6061 | 6061-T6 (ASTM) = A6061 (JIS) = 6061 (GB) |
Titanium Alloy Round Bar, Ti-6Al-4V | Jet engine shafts, biomedical implants, aerospace fasteners | ASTM B348 | JIS G4600 TC4 | GB/T 2965 TB2 | Ti-6Al-4V (ASTM) = TC4 (JIS) = TB2 (GB) |
Key Point：Standard Application Scope and Material Form
Standard | Material | Description |
ASTM A276 | Round Bar, Flat Bar, Square Bar | Applicable to cold drawn, hot rolled, and forged stainless steel bars. Surface finish may be bright, polished, or black (as-rolled). |
JIS G4303 | Round Bar, Flat Bar | Specifically applicable to austenitic, martensitic, and precipitation-hardening stainless steels. Grades such as SUS304 and SUS630 fall under this standard.
|
GB/T 1220 | Round Bar, Flat Bar, Hex Bar | This is the unified Chinese national standard for stainless steel bars. 06Cr19Ni10 is the official Chinese GB grade designation for 304 stainless steel.
|
ASTM A510 | Wire Rod, Coarse Round Wire | Applicable to wire rods and coarse round steel wires. Not directly applicable to machined bars — this distinction should be noted.
|
ASTM A29 | Hot-Forged or Hot-Rolled Bar | Applicable to carbon and alloy steel forged/hot rolled bars, such as 4140, 4340, 45#, etc. |
Specification of Steel Round Bar
The manufacturing process heavily influences which standard applies and the achievable tolerances and surface finish.
Hot Rolled Steel Round Bars
Standards: EN 10060, ISO 1035-1, ASTM A29
Diameter Range: Typically from 5 mm to over 500 mm. For example, hot-rolled bars are available from 6 mm to 110 mm under EN 10025, and from 16 mm to 510 mm under EN 10060 .
Surface Finish: As-rolled, often with a rough, black (mill) scale surface.
Tolerances: Defined by standards like EN 10060 .
Cold Drawn / Bright Steel Round Bars
Standards: EN 10277, ASTM A108
Diameter Range: From 5 mm to 100 mm under EN 10277 .
Surface Finish: Smooth, bright, and precise with tighter dimensional tolerances (e.g., tolerance class h9 per ISO 286-2) .
Forged Steel Round Bars
Standards: EN 10250 (for open die steel forgings)
Diameter Range: Often used for larger diameters. For example, diameters greater than 300 mm are typically forged.
Surface Finish: Can be peeled (machined) to a smooth finish or left as-forged.
Manufacturing Process of Steel Round Bar:
