大型挖掘机支座制芯工艺探讨

Discussion on Core Making Technology of Large Excavator Support

利用呋喃树脂砂、碱酚醛树脂砂及水玻璃砂制芯工艺制备的大型挖掘机支座存在裂纹倾向大、生产效率低的问题,需研究新的制芯工艺,以适应生产需求。经研究,覆膜砂壳芯工艺可取代手工呋喃树脂砂、碱酚醛树脂砂及水玻璃砂等传统制芯工艺,用于大型挖掘机支座的砂芯制备。壳芯工艺成功的关键是选择合适的壳型壁厚,设计合理的加强筋及排气通道。壳芯的应用可以消除支座内腔裂纹及气孔等铸造缺陷,大幅降低支座废品率,提高生产效率,从而降低生产成本。

The large excavator support prepared by the core-making process of furan resin sand,alkali phenolic resin sand and sodium silicate sand has the problems of large crack tendency and low production efficiency.It is necessary to study a new core-making process to meet production needs.According to the research,the coated sand shell core process can replace the traditional core-making process such as manual furan resin sand,alkali phenolic resin sand and sodium silicate sand,which can be used in the preparation of sand cores for large excavator bearings.The key to the success of the shell core process is to choose a suitable shell wall thickness,design a reasonable stiffener and exhaust channel.The application of the shell core can eliminate casting defects such as cracks and pores in the inner cavity of the support,greatly reduce the rejection rate of the support,improve production efficiency,and reduce production costs.