Calcined flint clay has been processed through a series of procedures, such as remove impurities, magnetic-selected to move iron and spraying drying etc. Water-washed kaolin has been used very effectively as functional filler in ceramic and so on.
Calcined flint clay is mainly used for manufacturing high-quality refractory products, refractory castable, sagger, kiln furniture, crucibles, ceramic fiber, precision casting sand, ceramics products, etc.
Features of calcined flint clay:
High refractoriness.
Physicochemical stability.
Volume density high.
Low porosity.
Low water absorption.
Fully calcined.
Low impurity content.
Pure white.
Specifications of calcined flint clay:
Size of particles: 0-1mm, 1-3mm, 3-5mm, 5-8mm, 8-15mm, 0-5mm, 0-50mm.
Size of sand: 8-16, 16-30, 30-60, 30-80, 60-80, 80-120 (mesh).
Size of powder: -200mesh, -270mesh, -325mesh.
Physical and chemical index of calcined flint clay:
| Item/Grade | YNS45 | YNS45 | YNS44 | YNS44 | YNS43 | YNS42 | YNS40 | YNS36 |
| A | B | A | B | |||||
| Al2O3 % | 46-48 | 45-48 | 44-48 | 44-48 | 43-48 | 42-46 | 40-46 | 36-42 |
| SiO2 % | 49-52 | 49-52 | 50-53 | 50-53 | 50-53 | 50-53 | 50-54 | 50-55 |
| Fe2O3 % (max) | 1.0 | 1.15 | 1.3 | 1.5 | 2.0 | 2.5 | 3.0 | 3.5 |
| TiO2 % (max) | 0.8 | 0.8 | 0.9 | 0.9 | 1.0 | 1.1 | 1.2 | 1.3 |
| K2O+Na2O % (max) | 0.3 | 0.3 | 0.4 | 0.4 | 0.4 | 0.5 | 0.5 | 0.6 |
| Ca0+Mg0 % (max) | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.6 | 0.7 | 0.8 |
| Bulk density g/cm3(min) | 2.58 | 2.55 | 2.52 | 2.50 | 2.45 | 2.40 | 2.37 | 2.30 |
| Refractoriness °C(min) | 1780 | 1770 | 1760 | 1750 | 1740 | 1720 | 1710 | 1700 |
| Impurities % (max) | 0.5 | 1.5 | 2.0 | 2.5 | 3.0 | 3.5 | 4.0 | |
