Silica insulating series, a kind of insulating refractory material with a content of SiO2 no less than 91%, is mainly made of silica rock. Besides of thermal insulating performance, it has kept most characteristics of silica series. It owns high refractoriness under load. During process of heating-up, its volume will be slightly expanded and the Integrity of furnace will be improved.
The producing process of silica insulating series includes: fine grinding silica rock which is main raw material of the series; adding part of waste silica bricks or waste silica insulating refractory brick powder, mineralizer and carbon powder; then mixing with water to obtain mud materials in mixing machine, based on a certain proportion; moulding by mechanical or handwork; drying moisture remaining in raw bricks to less than 0.5% and installing into furnaces to sinter. In addition, in order to prevent sharp volume expansion due to SiO2 polycrystalline transformation and cracks of products generated, the temperature of heating-up and cooling shall be slowly adjusted while sintering.
Silica insulating series is mainly used in external insulating layers of linings in glass furnace and similar parts of furnace in metallurgical industry.
This series is suitable to be used in lining or insulating layer of industrial furnaces which its long-term work temperature is not more than 1550ºC. And the brasque or insulating layer can not directly contact to high temperature melting materials as well as corrosive gas.
Silica insulating series owns abilities of relatively high refractoriness under load. Its linear expansion rate is higher than that of normal clay insulating materials and the attention shall be paid while working.
Furthermore, due to the dust of silica rock which can be harmful to human health, relevant personnel shall pay more attention on safety protection in processes of production and construction.
Physical and Chemical Indicators