fired bricks china

What should I do if there are under fired or over fired bricks

1、 Underfired bricks

In the process of producing sintered bricks in tunnel kilns, it is often found that there are severe underfired bricks on both sides of the bottom of the kiln car, which turn white in color; The strength is very low, resulting in a high crushing rate of finished bricks.

Reason:

The poor sealing of the kiln car and the entry of cold air from the bottom of the car into the kiln result in a decrease in temperature on both sides of the bottom of the billet stack, which is the main cause of underfired bricks;

The pressure, temperature, and atmosphere of the tunnel kiln are unbalanced, and the pressure inside the kiln is lower than the pressure below the kiln car;

Insufficient internal heat content in the 3 raw materials;

4. Insufficient production capacity, sintering time and insulation time.

Solution:

1. Check the seals between the kiln cars and the sand seals on both sides of the kiln wall, repair the air leakage in the sand seal groove in a timely manner, and ensure that there is enough sand in the sand seal groove to prevent cold air from entering the kiln from the bottom of the car;

2. Adjust the balance between positive pressure, zero pressure, and negative pressure inside the kiln, maintain the temperature of each zone inside the kiln, reduce the temperature difference between the top and bottom of the billet stack on the kiln car, and ensure the normal roasting and insulation of the billet;

Analyze the calorific value of the raw materials and increase the roasting temperature appropriately;

Strictly control the roasting and insulation time, strictly achieve “fixed belt, fixed temperature, and fixed time” for roasting and insulation, and do not affect quality based on single production.

2、 Overheated brick

In the process of producing sintered bricks in tunnel kilns, the bricks in the middle and upper parts of the brick stack show bending deformation or bubbles, commonly known as explosive bricks or over fired bricks.

Reason:

Excessive heat preparation in raw materials;

2. Unreasonable stacking of billets;

3. The roasting belt moves forward, and the roasting and insulation time is too long.

Solution:

Analyze the proportion of heat added to the raw materials and allocate the internal combustion heat value reasonably;

2. Improve the stacking method by appropriately increasing the gaps between the billet and the stack;

Strictly control the roasting and insulation time.