Galvanised steel, often referred to as simply "galvanized" steel, is a type of steel that has been coated with a layer of zinc. This protective layer helps to prevent corrosion and extends the lifespan of the steel. In order to properly specify or identify galvanised steel, it is important to understand the standard coding system used for this material.
The role of standards in coding
Standards play a crucial role in the world of galvanised steel coding. They provide a universally accepted set of rules and guidelines that help ensure consistency and accuracy in identifying and categorising different types of galvanised steel.
ASTM International coding system
The most widely used coding system for galvanised steel is developed by ASTM International (formerly known as the American Society for Testing and Materials). ASTM A653/A653M is the standard specification for steel sheet, zinc-coated (galvanised) or zinc-iron alloy-coated (galvannealed) by the hot-dip process. This specification covers various grades of galvanised steel with different coating weights and surface finishes.
For example, G90 indicates that the total weight of zinc coating on both sides of the steel sheet is 0.9 ounces per square foot, while G60 represents a coating weight of 0.6 ounces per square foot. The letter designation following the numerical value specifies the surface finish, such as A for regular spangle, B for minimized spangle, and C for no spangle.
Other coding systems
In addition to the ASTM coding system, other organisations and countries have their own coding systems for galvanised steel. For instance, European standards are designated with the prefix EN. The European standard for continuously hot-dip coated steel flat products is EN 10346. This standard includes specific coating designations, such as Z275 for a coating weight of 275 grams per square meter.
It's worth noting that while different coding systems may vary in their specific designations and terminology, the underlying purpose remains the same – to provide a consistent and reliable method for identifying and specifying galvanised steel.
Conclusion
In conclusion, the code for galvanised steel refers to the standards and specifications used to identify and categorise this type of steel. The ASTM International coding system, such as ASTM A653/A653M in the United States, is widely recognised and commonly used. However, other coding systems, such as those used in Europe, also exist. Understanding these coding systems is essential for accurately specifying galvanised steel and ensuring its quality and performance in various applications.