本文试验研究了在砂型顶面用不同方法(盖塑料膜、喷水、喷粘土浆、撒粘土粉和细砂等)施加软复盖对砂型气流紧实效果的影响。试验表明:只要在砂型顶面形成一层不透气的软隔膜,均可提高气流紧实的效果;并改善砂型背面的松散状态。其中以复盖塑料膜最为简单可靠,软复盖的气流紧实还显著地提高低矮砂型的紧实效果。 In this paper, the effect of soft cover applied on the top of sand mold with different methods (cover plastic film, water spray, clay sprayed clay, clay and fine sand, etc.) on the compaction of sand-type air stream was experimentally studied. Experiments show that as long as a layer of air-impermeable soft membrane is formed on the top of the sand mold, the air-tightness can be improved and the looseness of the back of the sand mold can be improved. One of the most simple and reliable to cover the plastic film, soft cover airflow tight also significantly improve the low sand compact effect.