The steel rail is the main component of the train tracks. It directly bears the repeated impact loads of the wheels of the rolling stock. It is also the basis for ensuring the safe, stable, and fast transportation of the train.
What are the specifications for railway track material?
Railway tracks are composed of multiple components, with steel rails being the most critical material, providing the structural pathway for trains and distributing wheel loads to sleepers and ballast. The material specifications of rails directly affect track durability, safety, and maintenance cycles. Various international standards define the composition, mechanical properties, and dimensions of steel rails for different types of railways.
What Metals Are Used in Railway Tracks?
Rail steel is a high-carbon alloy steel designed for high strength, wear resistance, and fatigue life. The main metals and elements in rail steel include:
| Element | Typical Content (%) | Purpose |
|---|---|---|
| Carbon (C) | 0.65–0.80 | Provides hardness and tensile strength |
| Manganese (Mn) | 0.70–1.40 | Enhances toughness and wear resistance |
| Silicon (Si) | 0.15–0.35 | Improves strength and elasticity |
| Chromium (Cr) | 0–0.40 | Enhances wear and corrosion resistance in some rails |
| Vanadium (V) | 0.03–0.12 | Refines grain and increases fatigue resistance |
| Phosphorus (P) | ≤0.04 | Limits brittleness |
| Sulfur (S) | ≤0.04 | Reduces the risk of cracks |
For example, a U71Mn rail-common in Chinese heavy rail lines-contains 0.65–0.76% C, 1.10–1.40% Mn, and 0.15–0.35% Si, offering excellent fatigue and wear resistance for high axle loads.
What Are the Standard Grades of Rail Steel?
Rail steel is categorized into grades according to international standards, with each grade specifying chemical composition and mechanical properties:
| Standard | Grade | Yield Strength (MPa) | Tensile Strength (MPa) | Hardness (HB) | Typical Application |
|---|---|---|---|---|---|
| GB (China) | U71Mn | – | ≥880 | 240–270 | Heavy railways, high-speed lines |
| GB (China) | U75V | – | ≥980 | 240–270 | High-speed and freight rail |
| EN / UIC | R260 | – | ≥880 | 260–300 | European mainlines |
| EN / UIC | R350HT | – | ≥1175 | 350–390 | High-speed rail |
| JIS (Japan) | 60N | – | ≥500–650 | – | Urban and regional railways |
| AREMA / ASCE | 115RE | – | ≥880 | 240–270 | North American mainline rail |
The yield strength, tensile strength, and hardness are critical for rails to resist bending, wear, and fatigue over long-term operations.
What Are the Common Rail Types and Their Material Properties?
Rails are also categorized by weight per meter, which correlates with structural performance. Typical international rails include:
| Rail Type | Weight (kg/m) | Standard | Material Grade | Application |
|---|---|---|---|---|
| Light Rail | 22 | GB11264-89 / JIS 22KG | Q235 / 55Q | Urban trams, light-duty lines |
| Medium Rail | 50 | GB2585-2007 / UIC54 | U71Mn | Regional and freight lines |
| Heavy Rail | 60 | GB2585-2007 / UIC60 | U71Mn | Mainline, high-speed, heavy freight |
| Crane Rail | QU100 / QU120 | YB/T5055-93 | U71Mn | Industrial yards, ports, cranes |
The weight per meter ensures the rail can withstand train axle loads without excessive deflection or wear.
How Are Rails Produced?
Steel rails are produced using hot-rolled steel, usually from oxygen-converter or electric-furnace steel. Some high-speed or heavy-duty rails undergo head-hardening, which increases wear resistance on the railhead. Quality checks include:
- Dimensional verification (head, web, foot)
- Mechanical testing (tensile, yield, hardness)
- Chemical composition validation
- Non-destructive testing for internal cracks
GNEE RAIL supplies rails meeting GB, UIC, AREMA, DIN, JIS, and Australian standards, with full testing documentation and technical support for installation and maintenance.
| Standard | Sepc. | Material Typical Grade |
| UIC860 | UIC54 | 700,900A,900B |
| UIC60 | ||
| EN13674.1 | 5.00E+02 | R200,R350HT,R260Mn,R35LHT,R320Cr,R370CrHT |
| 5.40E+02 | ||
| 6.00E+02 | ||
| 6.00E+03 | ||
| BS-11-1985 | BS80A | 700,900A,900B |
| BS90A | ||
| BS100A | ||
| AREMA | 115RE | SS,HH,LA,IH |
| 136RE | ||
| ASCE60 | U71Mn | |
| ASCE85 | U71Mn | |
| GB 2585-2007 | 50kg/m | U71Mn |
| 60kg/m | U75V | |
| 75kg/m | ||
| TB/T2344-2012 | 50kg/m | U71Mn,U75V,U77MnCr |
| 60kg/m | U78CrV | |
| 75kg/m | ||
| GB 11264-1989 | 8kg/m | Q235 |
| 12kg/m | Q235 | |
| 15kg/m | 55Q, Q235 | |
| 18kg/m | 55Q, Q235 | |
| 22kg/m | 55Q, Q235 | |
| 24kg/m | 55Q, Q235 | |
| 30kg/m | 55Q, Q235 | |
| 38kg/m | 50Mn, U71Mn | |
| 43kg/m | 50Mn, U71Mn | |
| GB Crane rails | QU70 | U71Mn |
| QU80 | U71Mn | |
| QU100 | U71Mn | |
| QU120 | U71Mn |