Carbon Steel Flat Bar Product Overview
Carbon steel flat bar is one of the most versatile sections in metal distribution. Its rectangular cross-section and clean edges make it ideal for frames, brackets, machine parts, agricultural equipment, and general fabrication. Huaxia-Steel supplies hot-rolled, cold-drawn, and slit-from-plate flat bar in Q235B, Q345B, A36, 1045, S45C, and other grades with mill certificates and export packaging.

Standard Sizes and Specifications
| Parameter | Range |
|---|---|
| Thickness | 3 mm – 100 mm |
| Width | 10 mm – 300 mm |
| Length | 3,000 mm / 6,000 mm, or cut to length |
| Tolerance | ASTM A6 / EN 10058 / GB/T 704, or tighter on request |
| Surface | Hot rolled black, pickled, cold drawn bright, shot blasted |
| Edge condition | Sheared edge, slit edge, or machined edge |
Available Steel Grades
| Grade | Standard | Typical Application |
|---|---|---|
| Q235B | GB/T 700 | General fabrication, brackets, frames |
| Q345B / Q355B | GB/T 1591 | Heavy frames, cranes, structural supports |
| A36 | ASTM A36 | Structural and welded fabrications |
| 1045 / S45C / C45 | ASTM A830 / JIS G4051 / EN 10083 | Machined parts, shafts, keys, wear strips |
| 1018 | ASTM A108 | Cold formed parts, pins, light brackets |
Manufacturing Standards
Our carbon steel flat bar is produced and inspected in accordance with internationally recognized standards:
- ASTM A36 / A6: structural carbon steel and dimensional tolerances
- ASTM A108: cold-finished carbon steel bars
- EN 10025-2: structural steel grades including S235JR and S275JR
- EN 10058: tolerances for hot-rolled flat bars
- GB/T 704 / GB/T 706: Chinese dimensional standards
- JIS G3101 / JIS G4051: Japanese structural and machine-use grades

Applications
- Machine frames, base plates, and mounting brackets
- Agricultural equipment parts and wear strips
- Construction and infrastructure projects
- Truck bodies, trailers, and transport equipment
- General fabrication and repair work
- Shaft keys, shims, and spacers when precision-cut
Quality Assurance
Every heat is supplied with an EN 10204 3.1 mill test certificate showing heat number, chemical composition, mechanical properties, and dimensional verification. Additional services include:
- PMI (Positive Material Identification)
- Hardness testing
- Third-party inspection by SGS, BV, or TUV
- Ultrasonic testing for plate-origin flat bar
- Dimensional reports on request
Packaging and Shipping
Flat bar is bundled with steel straps, ends protected, and surface oiled for ocean transport. Options include plastic wrapping, waxed paper interleaving, wooden pallet, and wooden crate. Standard export packaging prevents rust and deformation during transit.

Request a Quotation
Send us your grade, thickness, width, length, quantity, and destination port. Our team will reply with a competitive factory-direct quotation, lead time, and shipping options within 24 hours. Contact Huaxia-Steel now.





