Cement brick production method

Cement bricks and unfired clay cement bricks are new bricks made of clay mixed with a small amount of cement and admixtures, which do not need to be fired and are naturally cured. The production process is as follows:

I. Raw material selection

1. Clay: It must contain a certain amount of loose particles to facilitate mixing cement. Clay with less sand content can be mixed with sand in the soil. Clay with less sand content and harder must be ground before mixing with sand.

2. Cement: Adding 10% of 425# ordinary Portland cement can improve the strength and water resistance of the brick, and it will not crack after being soaked in water. Otherwise, general bricks will crack.

3. Admixture: Adding a small amount of admixture (reinforcement agent) can not only improve the hardening strength of the brick, but also reduce the amount of cement and reduce the cost of the product.

4. Water: The strength of the brick is high when the water content is appropriate. If the molding water content is small, the strength of the brick is poor, the material has great resistance in the mold, and the bottom of the brick is not dense when it is pressed on one side; if the molding water content is large, the bottom surface is wet, and it is easy to be damaged when it is removed from the mold. When the moisture content of sand is 3-5%, the water consumption during molding is preferably 10%. If there is too much fine sand in the raw material, it should be reduced to 8%.

2. Process operation

1. Mixing time: The longer the mixing time, the more evenly mixed it can be. The strength of dry mixing for 20 minutes is 15-23% higher than that of 10 minutes; the wet mixing time is preferably when the material does not clump. The storage time of the mixed material is preferably about 2 hours. Too long or too short a time will reduce the compressive strength of the brick.

2. Molding pressure: The pressure of clay cement brick during molding is best at 500 kilograms per square centimeter. Under this pressure, the product has high compressive strength and good water resistance. If the pressure is too low, it is not easy to compact.

3. Curing conditions: Clay cement bricks are generally protected by solar energy. The strength of the 7-day natural curing in the sun is equivalent to 67-90% of the strength of the 28-day age; the strength of the 28-day age is 80-95% of the strength of the quarter-year age. Therefore, if the curing site is small, the clay cement brick can be shipped after 7 days of natural curing.

Proportions of several materials for unburned bricks

Formula for unburned bricks 1. Fly ash bricks: 30% fly ash, 30% slag, 30% saltpeter (pebbles), 8-10% cement, 0.2% rock sand. (100kg/cm2 plus 8% cement, 150kg/cm2 plus 10% cement)

Formula for unburned bricks 2. Saltpeter bricks: 60% stone powder, 3% saltpeter (pebbles), 8-10% cement, 3% quicklime, 0.2% ash powder.

Formula for unburned bricks 3. River sand bricks: ① 60% river sand, 30% stone powder, 10-15% cement, 0.5% mortar treasure. ② 0.2% ash powder king, 0.2% early strength agent, 0.2% potassium chloride. (Choose one)

Formula for unburned bricks 4. Shale bricks (after crushing): 90% shale, 8-10% cement, 0.2% rock sand, 0.2% potassium chloride.

5. Gold iron ore powder: 60% gold iron ore powder, 30% stone powder, 10-15% cement, 0.2% rock sand, 0.2% potassium chloride, 0.2% early strength agent.

6. High-dosage fly ash bricks: 60% fly ash, 30% slag, 8-10% cement, 0.2% rock sand, 0.2% early strength agent.

1. Clay: It must contain a certain amount of loose particles to facilitate mixing cement. Clay with less sand content can be mixed with sand in the soil. Clay with less sand content and harder must be ground before mixing with sand.

2. Cement: Adding 10% of 425# ordinary Portland cement can improve the strength and water resistance of bricks, and will not crack after immersion in water. Otherwise, general bricks will crack.

3. Admixture: Adding a small amount of admixture (reinforcement agent) can not only improve the hardening strength of bricks, but also reduce the amount of cement and reduce the cost of products.

4. Water: The strength of the brick is high if the amount of water is appropriate. If the water content is low, the strength of the brick is poor, the material has great resistance in the mold, and the bottom of the brick is not dense when it is pressed on one side; if the water content is high, the bottom is wet and it is easy to be damaged when it is removed from the mold. When the moisture content of the sand is 3-5%, the water content during molding is preferably 10%. If there is too much fine sand in the raw material, it can be reduced to 8%.

Cement brick production process operation

1. Mixing time: The longer the mixing time, the more uniform the mixing. The strength of the dry mix for 20 minutes is 15-23% higher than that of the dry mix for 10 minutes; the wet mixing time is preferably when the material does not clump. The storage time of the mixed material is about 2 hours. If the time is too long or too short, the compressive strength of the brick will be reduced.

2. Molding pressure: The pressure of clay cement brick during molding is best at 500 kilograms per square centimeter. Under this pressure, the product has high compressive strength and good water resistance. If the pressure is too low, it is not easy to compact.

3. Curing conditions: Clay cement bricks are generally protected by solar energy. The strength of natural sun curing for 7 days is equivalent to 67-90% of the strength of 28 days; the strength of 28 days is 80-95% of the strength of one quarter. Therefore, if the curing site is small, clay cement bricks can be shipped after 7 days of natural curing.