1.4 : レンガ

Bricks are masonry units made from fired clay in various shapes, sizes, and colors.

Conventionally, bricks were made in a simple wooden mold, producing a fixed number of bricks at a single time.

Local clays and shales are used to manufacture bricks. The raw material is subjected to crushing, grinding, and screening for fine consistency.

This material is then mixed with water to create a pliable clay, and it is shaped into bricks either by a soft mud process, a dry-press process, or a stiff mud process.

Once the raw clay is shaped into bricks, they are air dried and exposed to high temperatures in kilns at eighteen hundred to twenty four hundred degrees Fahrenheit to prepare the bricks for construction use.

The exposure duration of bricks in the kilns is between 40 and 150 hours. Following this, controlled cooling measures are implemented to prevent thermal cracking in the bricks.

The temperature in the kiln affects the size and color of the bricks — higher temperatures result in more shrinkage and darker bricks.