轴承盖超声波探伤缺陷分析及改进

某型轴承盖轴承面经超声波探伤不合格。经分析主要原因是原工艺热冒口的冒口颈(内浇道)偏小,且开设的位置不合理,造成内浇道根部存在疏松和晶粒粗大铸造缺陷。新工艺利用均衡凝固理论,采用短、薄、宽内浇道分散引入,配合冷铁和保温冒口,加大激冷度,强化补缩;优化熔化工艺,改善内部组织;获得了高致密度要求的铸件。

Analysis and Improvement on UT Defects of Certain Type of Bearing Caps

The main reasons that result in the disqualification of bearing caps, bearing surface and UT is that the riser neck of primary hot feeder is too small and their positions are not reasonable so as to cause porosity and coarse grain in the root of riser neck. Based on the new equilibrium solidification theory, the dispersed gate with flat.thin and wide rise neck, coupled with cold iron and warming riser, was adopted in the new gating system. The system can increase chill degree, strengthen feeding, improve inner structure, and thus acquire desired castings with higher density.