对于大型零件退火,退火箱的封口过去一直采用钢板盖泥封法。由于钢板变形,封口泥经常干裂、漏气,使得靠近箱顶的工件质量不稳定。后来,我们摸索采用粘土—铁屑—焦炭粉覆盖法密封箱盖,取消了钢板,获得了良好的效果。 具体方法是:工件装箱后,至箱口留下约20mm的间隙,填入粘土(50％)—铁屑(30％,充当填 For annealing of large parts, the sealing of the annealing box used to use the steel plate cover mud seal method. Due to the deformation of the steel plate, the sealing mud often cracks and leaks, which makes the quality of the workpiece near the top of the box unstable. Later, we explored the use of clay - iron - coke powder cover sealing lid, canceled the plate, and achieved good results. The specific method is: After the workpiece packing, to leave about 20mm gap to the mouth, fill in clay (50%) - iron filings (30%