The main differences between low porosity clay bricks and ordinary clay bricks are as follows:

I. Porosity

Low porosity clay brick: the porosity is usually lower than 17%, and even lower than 12%. Low porosity makes the brick more compact and has stronger corrosion resistance.

Ordinary clay brick: the porosity is usually between 22% and 26%, the density is relatively low, and the erosion resistance is weak.

II. Strength

Low porosity clay brick: Because of low porosity, the brick structure is more compact, and its compressive strength and cold compressive strength are significantly higher than those of ordinary clay bricks. For example, the compressive strength of DN-12 clay brick with low porosity at room temperature can reach 68 MPa.

Ordinary clay brick: its strength is relatively low, and it is mainly used in general industrial furnaces.

III. Fire resistance

Low porosity clay brick: the fire resistance is usually above 1400°C, and some models are even higher, which is suitable for high temperature environment.

Ordinary clay brick: the fire resistance is generally between 1250 C and 1350 C, which is suitable for low temperature environment.

IV. Erosion resistance

Low porosity clay brick: due to its low porosity and high density, it has stronger tolerance to acidic and alkaline slag and chemical substances, and is especially suitable for high-temperature equipment in metallurgy, chemical industry and other industries.

Ordinary clay brick: its corrosion resistance is relatively weak, and it is mainly used in weak acid environment.

V. Thermal conductivity and thermal insulation performance

Low porosity clay brick: low thermal conductivity, better thermal insulation performance, which can effectively reduce heat loss.

Ordinary clay brick: high thermal conductivity and relatively poor thermal insulation performance.

VI. Service life

Low porosity clay brick: the service life is 2 to 3 times longer than that of ordinary clay brick, with better stability and no sudden change in erosion degree.

Ordinary clay brick: short service life, suitable for occasions with low requirements on refractory performance.

VII. Production technology

Low porosity clay brick: high pressure forming and high temperature sintering are usually used, and the sintering temperature is high. Flint clay and other additives are added to the raw materials to further reduce the porosity.

Ordinary clay brick: the production process is relatively simple and the sintering temperature is low.

VIII. Application areas

Low porosity clay brick: widely used in high temperature equipment such as blast furnace, converter, glass kiln and cement kiln.

Ordinary clay brick: suitable for permanent layer of furnace lining and flue at low temperature.

IX. Appearance and color

Low porosity clay brick: the appearance color is usually red, and the section is relatively dense.

Ordinary clay brick: yellowish in color and coarse in section.

To sum up, low porosity clay brick is obviously superior to ordinary clay brick in performance, especially suitable for high temperature environment with high requirements for refractory performance. Ordinary clay bricks are more suitable for general industrial furnaces.