What kind of steel are rails made of?
Jan 14, 2026
What kind of steel are rails made of?
Steel rails are a core component of railway tracks, guiding train wheels and transferring enormous loads to the sleepers. Rails are primarily made of high-strength, wear-resistant steels. For heavy-duty applications such as crane rails (QU70-QU120) and heavy rails (50-75 kg/m), manganese-carbon steels like U71Mn are the industry standard. U71Mn offers high tensile strength, excellent toughness and good wear resistance, making it suitable for concentrated loads and industrial environments. Higher-grade rails such as U75V or the European R350HT steel are used for high-speed or extremely heavy load lines.
Steel grade comparison table
| Grade | C (%) | Si (%) | Mn (%) | Tensile (MPa) | Elongation (%) | Hardness (HB) | Typical application |
|---|---|---|---|---|---|---|---|
| U71Mn | 0.65-0.76 | 0.15-0.35 | 1.10-1.40 | 880 min | 9 min | 240-270 | Heavy rail, crane rail |
| U75V | 0.71-0.80 | 0.50-0.80 | 0.70-1.05 | 980 min | 9 min | 240-270 | High-speed and heavy rail |
| 50Mn | 0.48-0.56 | 0.17-0.37 | 0.70-1.00 | 645 min | 13 min | - | Medium rail |
| Q235 | 0.12-0.20 | 0.30 max | 0.30-0.70 | 375-460 | 26 min | - | Light rail, industrial tracks |
How heavy and light rail standards differ across countries
Rail standards vary internationally, reflecting differences in load requirements, climate and operational conditions. Rails are manufactured to GB, UIC, AREMA, BS, DIN and JIS standards to ensure compatibility with local and international projects. For example, UIC 60 rails are commonly used on European high-speed lines, while ASCE 60 or 75 rails meet American heavy rail requirements.
| Standard | Rail type | Weight (kg/m) | Material | Typical application |
|---|---|---|---|---|
| GB 2585-2007 | Heavy rail | 50-75 | U71Mn / U75V | Chinese high-speed and heavy-load lines |
| UIC 860 | Heavy rail | 50-60 | 900A / 1100 | European mainline tracks |
| AREMA / ASCE | Heavy rail | 60-136 | U71Mn and equivalents | American freight and industrial tracks |
| JIS E 1103 | Light / medium rail | 15-50 | Carbon steel | Japanese industrial and passenger lines |
| GB/T 11264 | Light rail | 6-30 | Q235 / 55Q | Urban transit and light industrial tracks |
Common rail processing operations
Rails are usually delivered as rolled lengths and then processed for the specific track design. Typical operations include hot or cold bending for crane and mining curves, precision drilling of fishplate or bolt holes, angle cutting for welded joints, end milling or grinding for long-rail welding alignment, sandblasting for surface preparation and anti-rust oiling for marine transport, plus rail welding to form continuous track.
FAQ
Why is U71Mn the standard steel for heavy rails?
U71Mn combines a minimum tensile strength of 880 MPa, toughness and wear resistance with good weldability, which is why it dominates heavy rail and crane rail production.
What is the hardness of U71Mn rail steel?
U71Mn rails develop a hardness of 240-270 HB, giving the running surface strong resistance to wheel wear.
What steel is used for high-speed rails?
High-speed lines use higher-strength grades such as U75V (980 MPa minimum) or heat-treated head-hardened steels equivalent to R350HT under EN 13674-1.
Can Q235 steel be used for mainline rails?
No. Q235 is limited to light rail and industrial tracks; mainline service requires U71Mn, U75V or higher grades.
How do I select the steel grade for a crane rail?
Crane rails are normally specified in U71Mn with a hardened head to resist the concentrated wheel loads of crane trolleys, with the section chosen from QU70 to QU120 by crane capacity.
Are rails from different standards interchangeable?
Not without verification. Section height, head and base width and web thickness differ between standards, so equivalent profiles must be checked dimensionally before substitution.
