Construction procedure of refractory castable

Inspection before construction

Pre-construction inspection shall be strictly carried out, including the following contents

1. Define the appearance and structure of casting material equipment and clean it

2. Setting of process holes

3. The construction machinery and tools must be in good condition, vibration tools and other parts must be in good condition

4. Type, size, arrangement and welding quality of the anchorage parts. Expansion compensation must be done for the metal anchorage parts

5. Around the fire brick heat insulation layer to do a good job of pouring material water loss (glue) preventive measures

6. Packing and delivery date of castable, and pre-test to check for failure

7. The quality of construction water must be potable water

8. Implementation of construction process formula

9. Pouring procedure

If the above inspection is unqualified, the construction can only be carried out after it is qualified. The expired and invalid materials shall not be used.

Template for construction

Can be made of steel or hard wood (bamboo).The formwork should have enough strength, good rigidity, no distortion, no displacement, no leakage of pulp.Steel template to use a mold remover, wood template to brush waterproof paint.Reused boards should be cleaned before use.

Construction of pouring material lining

3.1 construction of castable

3.1.1 stirring of castable

Stirring time should not be less than 5 minutes.The operation of the use of forced mixer, mixing should be first dry mix, and then add 80% of the solvent mixing, and then according to the dry and wet degree and the requirements of the construction of specific parts, and then slowly add the remaining solvent, until the appropriate working consistency.Under the premise of ensuring the construction performance, the amount of solvent should be less.Castable material should be used throughout the bag, and the finished mix of castable must be finished within 30 minutes.In the high - temperature dry operating environment is also appropriate to shorten the time.Castable which has been initially set or agglomerated shall not be used, nor shall it be stirred with solvent for reuse.

3.1.2 vibrating

Pouring material into the template should be immediately layered vibration with a vibrator, the height of each layer is less than 300 mm, vibration spacing to 2500mm is appropriate.When vibrating, try not to touch the anchor, do not damage the heat insulation layer, do not be in the same position of long vibration and revitalization.The vibrator should be drawn out slowly after the surface of the pouring material is pulped to avoid segregation and cavitation of the pouring material.After the completion of pouring, the pouring body can no longer be subjected to compression and shock before solidification.

3.1.3 pouring quantity and expansion joint

Each casting area shall be 1.5m squared (in sync with the amount of stirring). Expansion joints shall be reserved according to requirements (generally considered in synchronization during casting) and shall not be omitted.The expansion joints in the kiln and decomposition furnace are arranged in the axial direction of the annular ring with no less than 4 lines. Aluminum silicate fiber cotton felt is used as the material.

3.1.4 maintenance and stripping inspection

After the surface of castable is dried, necessary maintenance shall be carried out according to the requirements of construction maintenance, especially for the castable needing water maintenance, water shall be sprayed regularly to keep its surface moist.After the final setting of the pouring material, the side mold can be removed and continued to be sprayed with water for curing. However, the load-bearing template can be removed only after the strength reaches 70%. 

After the formwork is removed, the castable body should be inspected in time, and the quality problems such as honeycomb, peeling and cavity should be dealt with and repaired in time.When the problem is serious, the defect should be chipped away to expose the anchorage part, and then filled with homogeneous tamping material to continue curing.Do not cover problems with mud.

3.2 construction of composite lining

To the refractory and heat insulation compound lining should be layered construction, do not mix layer and slurry construction, heat insulation materials (such as silicon calcium board, silicon aluminum board, asbestos or slag cotton, etc.) should be sprayed with waterproof and moisture-proof materials.