Key Production Stages and Control Methods Affecting Brick Quality

Key Production Stages and Control Methods Affecting Brick Quality

Producing strong, uniform, and durable bricks is fundamental to the profitability and reputation of small-scale brick manufacturing projects. Quality is not accidental; it is achieved through meticulous control at every stage, from raw materials to curing. Controlling the following four core stages will fundamentally guarantee the quality of the bricks.

I. Raw Material Proportioning and Mixing: Laying the Foundation for Strength

This is the first step in determining the intrinsic strength of the bricks.

Key Control Points:

Stable Raw Material Quality: The specifications and quality of raw materials such as cement, sand, stone powder, or coal slag should be relatively consistent. Avoid frequently changing suppliers or using raw materials with excessively high clay content or variable composition.

Accurate Proportioning: Strictly weigh or measure according to the successful experimental formula. Cement content is crucial for strength; too much increases costs, while too little results in insufficient strength; the gradation (particle size distribution) of aggregates (sand, stone powder) affects density.

Even and Moderate Moisture Content: Water content is critical. Too little water results in a dry, loose mixture that is difficult to compact, making the brick blanks fragile; too much water makes the brick blanks too soft and prone to deformation, resulting in many internal pores and low strength after drying. The goal is a mixture that "forms a ball when squeezed by hand, but crumbles when dropped."

Thorough and Even Mixing: Ensure that all raw materials, especially cement and water, are thoroughly and evenly mixed in the mixer, without dry clumps or uneven color.

II. Forming and Pressing: Shaping the Appearance and Density

This is the key process that gives the bricks their shape and initial density.

Key Control Points:

Filling Quantity and Uniformity: The amount of mixture filled into the mold must be accurate, consistent, and evenly distributed. Too little material results in incomplete brick blanks and insufficient dimensions; too much material can damage the equipment due to excessive pressure, and the brick blanks will be too thick.

Forming Pressure and Time: Ensure that the equipment provides sufficient and stable forming pressure (or vibration force) and maintains sufficient pressing (vibration) time. Insufficient pressure or too short a time will result in loose internal structure and poor strength.

Mold Condition: The molds must be clean, free of residue, and accurately installed. Worn, deformed, or residue-containing molds will directly lead to inaccurate brick dimensions, rough surfaces, chipped edges, or difficulty in demolding. III. Demolding and Handling: The "Care Period" for Protecting the Green Bricks

Newly formed wet bricks are extremely fragile, and the handling at this stage determines their final appearance.

Key Control Points:

Smooth Demolding: Ensure the demolding mechanism operates smoothly, gently and vertically pushing or transferring the bricks onto the pallets, avoiding bumps or scratches.

Use Flat Pallets: Pallets must be flat, clean, and free from deformation. Twisted pallets can cause the bricks to deform under gravity.

Gentle Handling: Handle wet bricks carefully, avoiding vibration, tilting, or stacking, to prevent internal cracks or corner damage.

IV. Curing Management: The "Incubation" for Achieving Final Strength

The strength of the bricks "develops" in a suitable curing environment; it is not achieved overnight.

Key Control Points:

Resting Period: After molding, the bricks should rest on the pallets for at least 24 hours (depending on weather and formula) to allow for initial setting and gain sufficient strength before moving and stacking.

Moisture Curing: Initial curing (usually 3-7 days) must maintain a humid environment. This can be achieved by covering with plastic sheeting or regularly spraying with water (mist), preventing rapid moisture evaporation. Insufficient moisture will prevent proper cement hydration, leading to a significant decrease in strength and even surface cracking.

Avoid Direct Sunlight and Wind: The curing area should be shaded and protected from wind. Direct sunlight and strong winds can cause uneven drying and shrinkage of the bricks, leading to cracks.

Standardized Stacking and Sufficient Curing Time: Stacking should be neat and stable, with ventilation gaps. Bricks typically require about 28 days to reach their designed strength. Avoid premature handling or subjecting them to heavy pressure during the curing period.

In summary, producing high-quality bricks is a process with interconnected steps: a good formula is the foundation, careful pressing is key, gentle handling is the safeguard, and patient curing is fundamental. By establishing simple control standards in each step (such as fixed ratios, mold inspection, and recording curing time) and strictly adhering to them, you can consistently produce high-quality products and earn long-term market trust. Remember, quality is built into the product, not inspected into it.