Defective Bricks? Adjustments May Needed in These Steps

Defective Bricks? Adjustments May Needed in These Steps

When bricks exhibit defects such as cracking, chipped corners, or insufficient strength, the problem is usually not with the brick itself, but rather with a deviation in a certain step of the production process. By observing the characteristics of the defects, the key steps requiring adjustment can be quickly identified.

I. Adjustments for "Brick Cracking" (Cracks, Breakage)

This is usually related to raw materials and early curing.

Check Raw Materials and Mixing:

Causes: Raw materials (such as sand) have too coarse particles or poor gradation, lacking fine particle filling; poor plasticity of the raw materials; uneven mixing, inconsistent wet and dry conditions.

Adjustments: Optimize the raw material ratio, adding an appropriate amount of materials with good plasticity (such as fine clay). Ensure sufficient mixing time and water addition to make the mixture uniform in moisture content.

Check Post-Molding Treatment:

Causes: Wet brick blanks lose water too quickly in the early curing stage, such as from sun exposure or wind, leading to surface shrinkage and cracking.

Adjustments: Ensure freshly formed wet brick blanks are immediately moved to a cool, windless, and humid curing area for covering or quiet rest. Exposure to harsh environments is strictly prohibited.

Check the demolding process:

Cause: Excessive force during demolding causes internal damage to the still-low-strength brick blanks, resulting in hidden cracks.

Adjustments: Optimize the demolding mechanism or standardize manual operation to ensure smooth and vertical demolding.

II. Adjustments for "Brick Corner Loss, Edge Missing, and Inaccurate Dimensions"

This mainly refers to the forming and mold stages.

Check mold condition:

Cause: Severe mold wear, deformation, or edge damage; inadequate cleaning of the mold's inner wall, resulting in material sticking.

Adjustments: Immediately inspect and replace/repair worn molds. Maintain mold cleaning every shift and may use an appropriate amount of release agent.

Check material (filler) uniformity:

Cause: Uneven or insufficient filling of the mold with raw material, resulting in localized material shortages.

Adjustment: Adjust the feeding device to ensure the raw material evenly and sufficiently fills every corner of the mold.

Check Molding Pressure and Vibration:

Cause: Insufficient pressure or vibration time, resulting in loose brick edges and corners.

Adjustment: Appropriately increase molding pressure or extend vibration time (for vibration molding machines) to ensure compaction of edges and corners.

III. Adjustments for "Insufficient Brick Strength and Brittleness" This is a systemic problem requiring inspection throughout the entire process, from formulation to curing.

Check Raw Material Ratio:

Cause: Insufficient proportion of cement and other binding materials; excessive harmful impurities in the raw materials (such as soil and organic matter).

Adjustment: Strictly adhere to the verified ratio, ensuring accurate weighing. Strengthen raw material screening and control impurity content.

Check Molding Pressure:

Cause: Insufficient or unstable pressure in the brick-making machine, resulting in insufficient brick density.

Adjustment: Calibrate and ensure the molding pressure reaches the design value and remains stable.

Check Curing Conditions:

Cause: Inadequate curing is a common cause of poor strength. Problems include insufficient resting time, untimely watering and moisturizing, and excessively low curing temperature.

Adjustment: Establish and strictly implement a curing system to ensure the brick blanks are in a suitable temperature and humidity environment during the critical period (especially the first 3-7 days).

IV. Adjustments for "Loose Brick Surface and Uneven Color"

Check Mixing and Raw Materials: Ensure thorough mixing and uniform mixing of raw materials; check for any impurities of other colors mixed in.

Check the Molded Surface: For products with layered fabric, check if the fabric layer is sufficient and uniform.

Summary: Defects are Signals of Process Problems. Every defective brick is a "warning signal" from the production process. The adjustment approach should be: tracing back from the defective product to the corresponding production stage, and then systematically checking and calibrating the process parameters, equipment status, or operating procedures of that stage. It is recommended to establish simple production records so that when problems occur, the raw materials, pressure, and curing data at that time can be quickly retrieved for precise adjustments, rather than blindly trying different methods. Through this refined process control, consistently high-quality bricks can be produced.