What is flint clay?
Flint clay is a representive of Chinese refractory clay. Normally, flint clay means CALCINED FLINT CLAY, it is calcined clay ore. Its Al2O3 content is about 44%, Fe2O3 less than 2%, with stable compound and dense structure,fracture surface likes broken shells.
Flint clay has no fixed compound. It is like Kaolin clay (Al2O3/3SiO2=0.85), besides some free quartz, it also has very few ferro and alkalis mineral. Common color include: pure white, light gray, light tea-yellow, some are brown.
What can flint clay do?
Flint clay has refractoriness and sinterability. This compound of many aluminum silicate , main component is Al2O3 and SiO2. Oxide impurities will flux the material, lower its refractoriness. Lower the Na2O+K2O content, higher the refractoriness.
As Al2O3/3SiO2 ratio near theoretical value(A/S= 0.85), flint clay is purer, refractoriness is higher, and its sinterablity is better .Top grade fint clay can reach 1750℃ refractoriness, water absorbtion less than 5%, bulk density bigger than 2.55g/cm3.
Block photo
Specifications
| Item/Grade | YNS45 | YNS44 | YNS43 | YNS42 | YNS40 |
| AL2O3 % | 46-48 | 44-48 | 43-48 | 42-46 | 40-46 |
| SiO2 % | 49-52 | 50-53 | 50-53 | 50-53 | 50-54 |
| Fe2O3 % (max) | 1 | 1.3 | 2 | 2.5 | 3 |
| Ti02 % (max) | 0.8 | 0.9 | 1 | 1.1 | 1.2 |
| K2O+Na2O % (max) | 0.3 | 0.4 | 0.4 | 0.5 | 0.5 |
| Ca0+Mg0 % (max) | 0.5 | 0.5 | 0.5 | 0.6 | 0.7 |
| Bulk density g/cm³(min) | 2.58 | 2.52 | 2.45 | 2.4 | 2.37 |
| Refractoriness °C(min) | 1780 | 1760 | 1740 | 1720 | 1710 |
| Impurities % (max) | 0.5 | 2 | 3 | 3.5 | 4 |
Advantages
1.Heat insulation
2.heat preservation
3.low water absorption
4.construction easily
5.Good work ability
6.Strong adhesive power
