Steel rails, also known as railroad tracks or railway lines, are critical components of railway infrastructure. They provide a stable and durable surface for trains to travel on, ensuring safe and efficient transportation. The manufacturing process of steel rails involves several steps, from raw material preparation to final finishing.

How Are Steel Rails Manufactured?

The manufacturing process of railway tracks has evolved. The following steps are the modern level production process.

• Pretreatment

It starts with the pretreatment of molten iron. The main purpose is to further reduce the content of harmful impurities in the molten iron. The usual way is to desiliconize at the tap hole of the blast furnace, dephosphorize and desulfurize the molten iron in the hot metal tank car. Some also adopt the "tandem method" of steelmaking, that is, the dephosphorization and desulfurization of molten iron are first carried out, and then go to the converter for decarburization and smelting.

• Refining

Adopt the refining technology outside the furnace. The main function is to further adjust the molten steel composition and molten steel temperature, reduce the inclusion content, and ensure the accuracy of the molten steel composition during tapping.

• Vacuum Degassing

Vacuum degas the molten steel after steelmaking to further reduce the content of hydrogen, oxygen and other gases dissolved in the molten steel. By doing so, the influence of these gases on the performance of rail steel can be reduced. Usually degassing is realized by the VD method or by the RH method. After vacuum degassing, the hydrogen content (volume fraction) in the steel can be less than 2.5PPM, and the oxygen content (volume fraction) can be less than 20PPM, which is more conducive to improving the toughness of the steel.

• Continuous Bloom Casting

Put the molten steel into the ladle, and lift it to the top of the continuous casting machine by the overhead crane. Pour the liquid steel into the continuous casting machine to cast a slab. Without cooling, the steel slab or "blooms" is directly heated in the soaking furnace for a certain period. This softens the steel for further shaping. It is then get squirted with water at over 3700 PSI. the water jets strip off any iron oxide that's formed on the steel's surface leaving the steel slab ready to be shaped into railroad tracks.

The continuous casting process has been gradually improved in the past 20 years. Due to the use of protective casting, it can effectively prevent the secondary oxidation of the molten steel during casting. Besides, it greatly reduces the inclusions in the steel, and significantly improve the surface quality of the steel slab. Major steel rail manufacturers in the world have adopted continuous casting process to produce steel rails.

After taking the above measures, the smelting level of rail steel has reached a high degree of purity. For example, the fluctuation of carbon composition is controlled at about 0.06% (mass fraction).

It is discovered that all manufacturers that use melton iron pretreatment, out-of-furnace refining, vacuum degassing and continuous casting technologies have gained the very good physical quality of their rails. The content of hydrogen, oxygen, phosphorus, and sulfur are all very low, and the content of inclusions: Type A inclusions are less than class 1.5, and B, C, and D inclusions are less than class 1.0.

• Rolling

The steel slab is then directly entering a machine called rolling mill which squeezes the rectangular steel into T-shaped tracks and stretches the rails out more than quadrupling its length.

• Heat treatment

The popular heat treatment is quenching and tempering or slack quenching. Some countries tried to improve the yield strength and tensile strength of railroad tracks by controlling the temperature of rolling or online heat treatment. Full heat treatment stabilizes the microstructure of the rail.

• Straightening

After cooling, a straightening machine works on the railroad tracks from both horizontal and vertical directions.

• Inspection

Railroad track inspection is also an important step. Check the surface and inner defect of railroad tracks through ultrasonic and eddy current inspection.

• Sawing and drilling

Use a carbide machine with hard alloy to process and drill the railhead to obtain high accuracy.

As a professional steel rail manufacturer in china, we can provide quality and low price GB standard light railway steel rail. The common sizes light rail from GNEE RAIL includes 6kg, 9kg, 12kg, 15kg, 22kg, 30kg, 8kg, 18kg, 24kg and etc. standard of light rail include GB11264-89 standard and YB222-63 standard.

Heavy rail is one of rail types. By the material, heavy rail can be divided into (low) manganese rail steel, (low) copper rail steel, (low) silicon rail steel GNEE RAIL provide u71mn heavy 50kg train railway steel rail with low price, and common sizes include 38kg, 43kg, and 50kg. All of sizes are based on GB2585-2007 standard.

Crane rail is usually classified into GB standard QU70, QU80, QU100, and QU120. Crane rail is made of u71mn, and with YB/T5055-93 standard.

At GNEE RAIL, we specialize in providing a full range of rail components, including heavy rail,light rail, crane rail and rail fastening, as well as matching high-performance rail clips and fastening solutions. Backed by strict quality control and industry certifications, our products are engineered to meet international standards and diverse project demands.

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