EN 13674: Railway Track Rail Standards (Steel Grades & Profiles)

EN 13674 (specifically Part 1: Vignole railway rails 46 kg/m and above) is the definitive manufacturing standard for the steel rails that form the backbone of modern railway networks. It supersedes older classifications (like UIC 60 or S49), harmonizing the profiles into the “E” series (e.g., 60E1).

This standard is not just about shape; it is about Metallurgy. It defines the chemical composition, hardness levels, and rigorous testing protocols required to ensure a rail can withstand millions of axle passes without developing Rolling Contact Fatigue (RCF) or brittle fractures.

1. Steel Grades: From R260 to R400HT

The durability of a track depends on the hardness of the rail steel. EN 13674 categorizes steel grades by their minimum Brinell Hardness (HBW). The choice of grade is a trade-off between wear resistance and weldability.

• R260 (Standard Grade): The baseline Carbon-Manganese steel used for straight tracks and high-speed lines where wear is uniform.
• R350HT (Heat Treated): “Head Hardened” rails. Through a controlled cooling process, the rail head is made significantly harder to resist the grinding forces in tight curves and Heavy Haul operations.

2. Classification of Rail Steels

Selecting the right steel grade is crucial for Life Cycle Cost (LCC) management. Installing soft rail in a sharp curve leads to rapid wear; installing hard rail on a straight line is a waste of money.

3. The “E” Profiles (Geometry)

EN 13674 standardized the rail cross-sections. The profile name indicates the mass per meter and the specific geometry version:

• 60E1 (formerly UIC 60): The standard heavy rail (60 kg/m) for mixed traffic and high-speed lines in Europe.
• 54E1 (formerly UIC 54): Used for lighter traffic or older infrastructure upgrades.
• Profile Tolerance: The standard mandates strict tolerances (e.g., Crown Profile deviation ≤ 0.5mm) to ensure a perfect wheel-rail interface.

4. The Invisible Enemy: Hydrogen

A critical requirement of EN 13674 is Vacuum Degassing. During steel production, trapped Hydrogen gas can cause internal microscopic cracks (“Shatter Cracks” or Flaking) that grow over time, leading to sudden rail breaks. The standard mandates strict limits on hydrogen content (typically < 2.5 ppm) and 100% Ultrasonic Testing of the finished rail.