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How to determine the quality of high-alumina bricks when making your selection
2025-09-17
There are many high-alumina brick manufacturers in the market, each claiming their products are superior. However, without the ability to distinguish between good and poor-quality bricks, it’s easy to fall for misleading claims. To help you assess the quality of high-alumina bricks effectively, the editor from a Zhengzhou-based manufacturer shares the following methods for inspection and evaluation.
1. Do the specifications of Zhengzhou high-alumina bricks meet the requirements, and are the dimensions consistent?
2. Whether the strength of the high-alumina bricks meets the requirements can be determined not only by reviewing the test reports issued by the laboratory, but also by listening to the tapping sound on-site—high-alumina bricks produce a noticeably quieter sound compared to standard materials.
3. Whether the angle of the high-alumina brick is complete and straight, as well as the flatness of its exposed surface.
4. Does the color variation of Zhengzhou high-alumina bricks meet the project requirements? Some high-alumina bricks are available without black smoke.
5. Are there high-alumina bricks that haven’t been ignited or even burned through? The surface or core of low-alloy alumina bricks is a deep red, and they produce a muffled sound when tapped.
6. Whether or not high-alloy bricks are available. Particularly for dry-laid and thin-joint applications, high-alloy bricks are difficult to cut and grind. Over-fired high-alumina bricks have a darker color compared to standard high-alumina bricks. They often exhibit significant warping and deformation, and when tapped, produce a sharp, brittle sound—almost like metal.
7. Check whether the high-alumina bricks have any cracks. The "wind cracks" that typically occur during the cutting process can be identified by observing that high-alumina bricks fired under extreme conditions exhibit "fire cracks," which can be distinguished by their distinct tapping sound. Cracks on the surface or inside the high-alumina bricks can lead to freeze-thaw damage.
8. Check the compactness of the high-alumina bricks. The density can be influenced by examining both the cross-section of the dried mud blank and the cross-section of the finished high-alumina brick. Porosity, sand holes, water-cut layers, sand-cut layers, and high-alumina bricks containing impurities are all affected.
9. Check high-alumina bricks for frost (alkali) formation. High-alumina bricks that show frost buildup should not be used in foundations or damp areas, as severe frosting indicates a substandard product.
10. Additional inspections: If the soil contains excessive sand, check for sulfur particles or lime granules—particularly whether the lime has caused cracking. Also, verify if the high-alumina plates are saturated, frozen, or mixed with frozen soil. The presence of any of these conditions can compromise the quality of the high-alumina bricks, so careful observation and thorough inspection are essential.
11. Review the test reports issued by the high-alumina brick manufacturer. After the high-alumina bricks are delivered to the site, the project team will send samples to the laboratory for retesting. If the results of the retest fail to meet the relevant standards, it indicates that the quality of the materials on-site does not match the quality of the submitted samples.
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Address: Cuigou, Pingmo Town, Xinmi City, Zhengzhou, Henan Province
Phone:+86-371-63090999 63100777
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