The Importance Of The Application
The castable refractory is delivered to the customer for mixing with water and shaping, applying a dry-out program and the controlling of all these steps, after the obtainment and processing of the raw material by the manufacturer. This situation shows us that the manufacturer has 2 preprocessing but the user has minimum 5 integral proceses. Eventually the material should be accepted or rejected by the user.
The material can be stored for one year at a closed and dry place but it should not be stored more than 6 packages upon.
The mixer must be very clean. A bag of castable is charged to the mixer. (If there is a partical usage of a bag, to prevent seperation, you should mix all of the material before charging into the mixer.) You sholud add the water slowly until you realise fluency, rapid accession and until you reach the desired consistency to prevent castable agglomeration on the surface. The mixing time should be minimum. (1-2 minutes)
The case must be clean. The castable refractory should be mixed as dry and shoveled for a few times before addition of the water.
To prevent evaporation materials should be covered with polyethylene cover (wet bags should be used in order to prevent to have a weak surface). Maximum performance and strength is obtained about 20-30°C. Setting should be applied below 20°C. The duration is 24 hours.
Polyethylene cover should be removed and the castable should be cured for at least 24h. Temperature is raised to 300°C at a rate of 30°C / h and hold at this temperature about 5h. Than it is raised at a rate of 50°C / h to 800°C. It is again hold at this temperature for 5 hours and taken to the service.
It is advised to use anchorages shown above to provide a better adaptibility to the surface for castables. The anchorages should be attached by 20 cm distances on the surface and they should be 2 cm shorter than the thickness of the material. The schematic demonstration of the usage of the pins which are about 25-35 mm and are made of 308 or 310 quality of steel to increase the modulus of reptures of materials and to prevent micro cavities caused by thermal and mechanical shocks.