在铸造行业中，珍珠岩主要用作保温材料，如铸钢及铸铁浇包的覆盖剂、保温冒口材料等。近年来，生产实践发现，珍珠岩还是铸件嵌铸孔中的一种良好的填充剂。比如有的单位将珍珠岩用于充填铸铁中嵌的铸钢管，取得了良好的效果，很好的解决了嵌管管壁烧穿问题。而我们用珍珠岩作? In the foundry industry, perlite is mainly used as insulation materials, such as casting agent of cast steel and cast iron, thermal insulation riser materials. In recent years, production practice has found that perlite is also a good filler in the castings of castings. For example, some units of perlite are used to fill the cast iron tube embedded in cast iron, which has achieved good results and well solves the problem of burying through the tube wall. And we use perlite for?