Curing and drying of refractory castables

After completing the installation of refractory castables, the kiln must undergo drying and curing. Proper curing and drying are crucial for the kiln's subsequent operation. Not only do they extend the kiln's service life, but they also prevent cracking, spalling, or explosions. Therefore, thorough curing and drying are essential for future use. Next, we will introduce the curing and drying processes for refractory castable furnace linings.

I. Curing and Baking Requirements

1. Curing: After 24 hours of hardening following castable installation, the formwork may be removed and natural curing initiated. Watering is strictly prohibited during curing. The cast structure must not be subjected to vibration or impact. Optimal curing temperature ranges from 15-30°C. When temperatures fall below 15°C, heating measures must be implemented. Total curing duration shall not be less than 3 days.

2. Baking: Baking is a critical step for extending the service life of furnaces, kilns, and thermal equipment. Its primary functions are to remove free water and chemically bound water from the furnace structure and to achieve high-temperature performance characteristics. Improper baking, inadequate moisture removal, or uneven heating during the process can cause cracks in the furnace structure, reduce strength, and in severe cases, lead to large-scale spalling or even explosions. Baking must be conducted strictly according to the baking schedule.

II. Precautions for Kiln Firing

1. Kiln drying must be conducted continuously without interruption. Strictly adhere to the principles of gradual temperature increase, appropriate holding time, and thorough drying both inside and out to prevent cracking and localized explosions.

2. The use of wood for drying is strictly prohibited! Wood drying cannot accurately control temperatures, making it highly prone to causing accidents such as kiln cracking or explosions.

3. If the kiln temperature significantly exceeds the specified limit, immediately maintain the current temperature without attempting to reduce it. Should substantial steam emission occur during drying, cease temperature increases and maintain the current temperature until steam emission subsides or ceases.

4. If forced to halt drying operations, implement measures to minimize temperature decline.

5. Production may commence immediately upon completion of the drying cycle.

The above outlines requirements and recommendations for the curing and drying of high-temperature kilns after construction. Strict adherence to drying procedures is essential to prevent a series of issues during subsequent kiln operation.