How are tiles made step by step?

The process of making tiles involves several key steps, transforming raw materials into durable and aesthetically pleasing products. Here's a step-by-step guide:

1. Raw Material Preparation:

• Sourcing: The process begins with sourcing the primary raw materials, typically clay, silica sand, feldspar, and other minerals. The specific composition depends on the type of tile being manufactured (e.g., ceramic, porcelain).
• Cleaning and Crushing: The raw materials are cleaned to remove any impurities and then crushed into smaller pieces to ensure a consistent mixture.

2. Mixing and Grinding:

• Batching: The crushed materials are carefully weighed and measured according to a specific recipe (or batch) to achieve the desired properties in the final tile.
• Wet Grinding: The measured materials are mixed with water in large mills. These mills grind the materials into a fine slurry, also known as slip. This process ensures a homogeneous mixture and reduces particle size for better tile quality.

3. Forming the Tile:

• Spray Drying (for Porcelain): For porcelain tiles, the slip is typically spray-dried to create a fine, flowable powder. This powder is then fed into presses.
• Pressing: The powder (for porcelain) or the slip (for some ceramic tiles) is fed into high-pressure presses. These presses compact the material into the desired tile shape and size. Pressure can range from hundreds to thousands of tons, depending on the tile size and material.
• Extrusion (Less Common): Some tiles, particularly quarry tiles, are made by extruding the clay mixture through a die. The extruded material is then cut to the desired length.

4. Drying:

• Controlled Environment: The pressed tiles are carefully dried to remove moisture and prevent cracking or warping. This is typically done in a controlled environment with specific temperature and humidity levels.

5. Glazing (Optional):

• Application: If a glazed finish is desired, a liquid glaze is applied to the tile surface. This can be done through spraying, pouring, or screen printing. The glaze provides color, texture, and a protective layer.
• Glaze Composition: Glazes are composed of various materials, including silica, fluxes, and colorants, that melt and fuse to the tile surface during firing.

6. Firing:

• Kiln Process: The tiles are then fired in a kiln at high temperatures. The specific temperature and firing cycle depend on the type of tile.
  • Ceramic Tiles: Typically fired at lower temperatures (around 1000-1300 °C).
  • Porcelain Tiles: Fired at higher temperatures (around 1200-1400 °C) to achieve vitrification (low porosity).
• Chemical Transformations: During firing, the materials undergo chemical transformations, fusing together and hardening into a durable product.

7. Sorting and Quality Control:

• Inspection: After firing, the tiles are carefully inspected for any defects, such as cracks, chips, or variations in color or size.
• Sorting: Tiles are sorted according to quality and grade.

8. Packaging:

• Protection: Finally, the tiles are packaged for shipment, typically in cardboard boxes, to protect them from damage during transportation.