摘要
介绍了灰铸铁数控机床底座铸件的结构及技术要求,详细阐述了原铸造工艺及存在的缩孔、缩松及变形问题,通过增大球形冒口尺寸,在热节处增加冷铁进行激冷,使厚壁区域提前凝固,实现铁液的顺序凝固;通过提高废钢的加入比例,提高锰含量的控制中值,降低碳含量及硅含量的控制中值,保证珠光体的体积分数,从而保证铸件的硬度;通过增加加强拉筋,防止在凝固过程中铸件收缩变形.生产结果显示:连续生产的10件机床底座铸件顶面无缺陷,粗加工后未发现缩孔、缩松缺陷,变形量控制在2 mm以内,改进效果明显.
Abstract
The structure and technical requirements of the gray iron machine tool base were introduced,original casting method and process,and caused shrinkage cavity and porosities as well as the deformation defects were described in details.Through increasing spherical riser dimensions,setting chills to chill hot spots to earlier solidify and thereby to realize earlier solidification.Through increasing steel scrap adding ratio,increasing the control median of manganese content,decreasing carbon content and silicon content to ensure pearlite volume fraction and thereby ensure casting hardness.Through adding strengthening ribs to prevent casting contraction deformation.Production results showed:continuously producing 10-piece machine tool base castings having not defect on top surface,not shrinkage cavity and porosities,the deformation was controlled less than 2 mm.Improving effect was obvious.
维普
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