France uses several steel numbering systems, including the French Standard or AFNOR, the France-based UIC Standard, and the France-based EN Standard.
AFNOR steel grades are commonly designated using the following format:
XCXX–XX–XX, where:
• XC represents the steel category, e.g. XC18 = general construction steel
• XX is a numeric code indicating the steels mechanical properties
• XX is a numeric code indicating the steels chemical composition
• XX is an optional code indicating a specialty addition or specific treatment
The UIC Standard for steels uses the following numbering system:
UXX–XXXX, where:
• U represents the steel category, e.g. U48 = structural steel
• XXXX is a numeric code indicating the steels structural properties
The EN Standard for steels uses the following naming system:
EN XX–XX–XX, where:
• EN is an abbreviation of the French word, Enseigne (standard)
• XX is a code indicating the steels mechanical properties
• XX is a code indicating the steels chemical composition
• XX is an optional code indicating a specialty addition or specific treatment
All three numbering systems are used to indicate the specific grade of a steel and its various properties. Each system has its pros and cons and is tailored to specific applications. Knowing which number system will be the most useful when specifying or operating with steel is key.
The AFNOR system is the most commonly used in France, and is beneficial for general purpose steel products such as construction materials, pipes, and thin plates. The UIC Standard for steels is used for specific pieces of construction equipment, such as railway tracks and sleepers, which require certain levels of strength and durability. The EN Standard for steels is used for industrial and machine parts, such as motors and engine blocks.
Ultimately, the choice of numbering system for steel products depends on the application for which the steel will be used. The difference in strength and durability between steels varies significant, so it is important to take these factors into account when deciding which alloy is the most suitable. Furthermore, due to the availability of different grades and alloys, the various numbering systems can help those responsible for a product’s design narrow their choices down to the most suitable materials. Working with a qualified advisor in the field of steel engineering can be particularly helpful to guarantee that the most suitable steel is employed.
