How To Construct Refractory Castables

The construction of refractory castables should be carried out strictly by the construction specifications to ensure the construction quality and progress. During the construction period, the refractory materials should be kept in a ventilated and dry place. During summer construction, the refractory castables should be placed in a cool and dry place, and outdoor exposure is prohibited.

The following is the construction process of refractory castables:

1. Before construction, the construction equipment and construction site should be cleaned. No mud, sand, lime, silicate cement, or other debris should be mixed into the castables, and all tools and equipment in contact with the castables should not be sticky with the above substances.

2. The mixing of castables should use a forced mixer, and the mixing water must be clean water with a pH value between 6-8 and a dosage of 7-8%. It is strictly forbidden to mix castables of different brands or manufacturers until the materials are uniform.

3. When mixing, pour all the materials in the bag (including the main material and small bags of auxiliary materials) into the mixer. No residue can be left, and no part can be taken out for use. First dry mix for 2-3 minutes, then add water while mixing, wet mix for 3-4 minutes, and discharge the material only when it is evenly mixed. The mixed material should be used within 30 minutes.

4. Before pouring, apply a layer of engine oil to the casting surface of all molds, and all embedded metal parts should be coated with a layer of asphalt paint before pouring;

5. When pouring, pour to the specified thickness at one time, and then vibrate with a vibrator. The vibrator should be inserted straight, inserted quickly, and pulled out slowly, and the insertion depth should be 100mm to the next layer of lining to ensure the connection between the upper and lower linings. The insertion distance is 150-200mm. The vibration time for each time should be based on the return of the material surface (generally 20-40 seconds). The vibrator model is 50 or above to ensure sufficient vibration intensity.

6. Demolding can be done 24 hours after pouring. After demolding, it should be naturally cured for 24 hours. The curing temperature should be between 15-25℃, the curing humidity should not be less than 90%, and the total curing time should be more than 3 days.

7. After natural curing is completed, the furnace should be baked. The furnace should be strictly handled according to the drying system and the temperature should be raised slowly.