The tunnel kiln's control over the firing temperature is crucial during the production process; it must be neither too high nor too low, as either extreme can affect the quality of the fired product and reduce work efficiency. Thus, mastering the art of fire watching is essential.

How to Handle a "Big Fire"

1. During the formula preparation, reduce the amount of coal added; if it's coal gangue, decrease the gangue content and increase the clay amount.

2. Speed up the import process, but this would result in an overly large "black heart" volume.

3. Reduce the air volume and inlet speed of the exhaust fan, lowering the firing temperature of the tunnel kiln. Adjusting the formula is an effective approach.

Two: High temperature in the sintering belt

When the temperature of the brick stack approaches the upper limit of its sintering temperature range, it is referred to as the high-temperature firing zone. At this point, the color of the brick body transitions from yellow to light yellow. The reason is either inaccurate control of the firing conditions or the failure to timely detect that the firing temperature has reached the sintering point.

Measures to be taken at this point include: cease adding coal when there's external coal combustion, and be attentive to any changes in the fire condition. Always remember not to pour water to cool down the fire from the fire hole during high temperatures, as this may cause the kiln's interior wall bricks to crack or damage the tunnel kiln.

Section 3: Low firing temperature encountered

The firing belt takes on a cherry red or light red hue, indicating the birth of bricks, yet the firing temperature cannot be elevated.

Possible reasons include: low combustion, incorrect use of the brake, and the combustion in the low-temperature section has been basically exhausted. By the time it reaches the high-temperature section, there is no coal left to burn, and the kiln workers failed to detect this in a timely manner. When there is insufficient airflow and low temperatures occur, coal powder is added to the fire mouth, and the flame progresses slowly or even stops. Conversely, if the flame quickly retreats, it indicates that the airflow is too great, blowing away the heat, preventing the temperature from rising.

Here's the content for this issue. The common problems in the production process of tunnel kilns mainly include these types. Whether the temperature is too high or too low, it will lead to a decrease in product quality. Therefore, if you encounter these situations, it's worth trying the above methods to resolve them.