Classification of Refractory Products according to EN 12475-1: Alumino-silicate Materials
The first part of the EN 12475 specification establishes strict criteria for the classification and nomenclature of shaped products based on alumino-silicate systems. EV Group China applies these standards to exclude the following product categories from the general list:
- Materials in which the content of metal oxides (excluding Al₂O₃, SiO₂, Fe₂O₃) exceeds 5%.
- Products with a carbon, carbide, nitride, or oxynitride content exceeding 1% by mass.
EN 12475-2: Basic (Refractory) Products with a Residual Carbon Content of Less Than 7%
This section regulates the classification parameters for shaped refractories, both with and without antioxidant additives. It is important to note that products with a carbon content of 7% and above after the coking process do not fall into this category. EV Group China supplies products of this group, taking into account the possibility of using metal frames or protective plates to increase structural strength.
Note 1: The classification of products with a carbon content of 7% to 30% is provided in Part 3 of the EN 12475 standard.
Note 2: Production technology allows for the use of external metal casings for all types of bricks, as well as the application of internal reinforcing plates for unfired products.
EN 12475-3: Basic Refractories with a Carbon Content of 7% to 30%
The third part of the standard covers the classification of shaped products that have undergone coking and retained 7% to 30% carbon in their structure. EV Group China ensures the supply of products in this group, including modifications with protective antioxidant additives, as well as variants reinforced with metal elements.
Note 1: For requirements regarding refractories with a carbon content below 7%, please refer to the requirements of EN 12475-2.
Note 2: Products can be supplied in a metal cassette or with internal metal plate reinforcement for operation in extreme thermal conditions.
EN 12475-4: Specific and Specialized Refractory Products
The fourth part of the standard establishes the nomenclature and classification features for special-purpose shaped products, divided into the following technological groups:
a) Oxide systems:
- Alumino-chromic oxide compositions.
- Zirconia-alumina refractories.
- Alumino-zirconia-silicate materials.
b) Combined oxide-non-oxide systems:
- Alumino-carbon refractories.
- Alumino-chromic oxide-zirconia-silicate compounds.
c) Non-oxide (oxygen-free) systems:
- Carbide compounds.
- Silicon carbide materials.
d) Other specialized products: This group includes materials that have a unique designation but do not fall under strict classification (e.g., products based on borides, nitrides, and their complex combinations).