我厂烘爐的火門盖(如圖1)內襯,只用廿几天就要換一次耐火磚,浪费很大。我們用修理冲天爐用的石英砂混合料来代替耐火磚修火門盖,得到了成功,使火門盖使用寿命延長了三倍。石英砂混合材料是用石英砂60％(粒度2～3公厘)、石英粉27％、甘子土13％(按重量比)配合成的,將三种材料在混砂机上加水13～15％,混制10～15分鐘,成为塑性良好的泥团。用鑄鉄做成与火門盖相似的心骨,用四个弯头螺釘固定在爐門外壳上,如圖2。心骨上塗一層泥漿水,然后將石英砂混合料摔貼到心骨上,并用砂椿用力搗实,將火門內襯修成如圖三的形狀,用压勺墁光。再用三公厘的气孔針在整个表面上札气孔(每平方英吋3～5个),使它不致發生裂紋。火門 I plant the oven door fire (Figure 1) lined with only a few days will change a refractory brick, waste a lot. We succeeded in replacing the firebrick fireproof door with the quartz sand mix used to repair the cupola, extending the life of the fire door threefold. Quartz sand is mixed with quartz sand 60% (particle size 2 to 3 mm), 27% quartz powder, 13% (in weight ratio) of Ganzi soil, the three materials in the sand mixer on the water 13 to 15% , Mixing 10 to 15 minutes to become a good plasticity of the mud. Made with cast iron and fire doors similar to the heart, with four elbow screws in the door shell, as shown in Figure 2. The heart of a layer of muddy water, and then drop the quartz sand mixture onto the heart, and with a pound hard pound, will be built into the fire door as shown in Figure three shape, with pressure spoon cellent. Use a three-millimeter stomatal needle across the entire surface of the sapphire pore (3-5 holes per square inch) so that it will not crack. Fire door