Foam glass (Cellular glass): Cellular glass takes glass dust as the basic material. Adds foaming agent and roasts into being through tunnel kiln. It is the best low-temperature heat-insulation material at present in the world markets. It is noted for its low unit weight, minor thermal conductivity, anti-moisture absorption, anti-mouldy, high mechanical strength, easy processing, resisting acid corrosion(except HF), nonpoisonous, stable chemical function, able to be used in a wide scope from extreme low to high temperature. Its excellent heat-insulation property can be last for many years without any degenerating. More important is that celluar glass itself is fireproof and shockproof. When it is used under such bad situations as extreme coldness, under-earth, open, easily fired, easily be damp and having chemical corrodent. It is not only safe but durable. It is be called "permanent heat-insulation material that not need be replaced" So it is widely used in oil chemistry, cold storehouse, under-earth project, ship-building, national defence and military project etc.