现代铸造

土木工程论文编号:TM010  论文字数:14321,页数:44

目录
摘要 I
ABSTRACT II

第1章 绪论 1
1.1 现代铸造的状况及发展趋势 1
1.1.1 铸造生产的特点 1
1.1.2国内外铸造技术的现状、存在问题及发展趋势 2
1.2计算机技术在铸造的应用 3
1.2.1计算机数值模拟的优点 4
1.2.2计算机辅助设计及铸造过程计算机模拟与传统铸造技术的比较 5
1.3课题的提出及研究内容 5
1.3.1课题的提出 5
1.3.2课题任务及研究内容 6
第2章 矿井天轮铸造工艺设计 7
2.1零件的铸造工艺性分析 7
2.1.1零件结构材质和技术要求 8
2.1.2铸件质量对零件结构的要求 8
2.1.3铸造工艺对零件的结构要求 8
2.2造型方法的选择 10
2.3工艺方案的确定 10
2.3.1浇注位置的确定 10
2.3.2分型面的确定 11
2.3.3铸件浇注温度的确定 11
2.4工艺参数的确定 11
2.4.1铸件尺寸公差 11
2.4.2机械加工余量 12
2.4.3铸件线收缩率 12
2.4.4起模斜度 12
2.4.5最小铸出孔 12
2.5砂芯设计 13
2.6浇注系统设计 13
2.6.1浇注形式及注入位置的选择 14
2.6.2铸件模数 15
2.6.3直浇道的位置和高度 15
2.6.4浇注时间的确定 16
2.6.5浇注系统的截面积 16
2.6.6冒口与冷铁设计 18
第3章 凝固过程数值模拟 21
3.1铸件凝固过程数值模拟技术的原理 21
3.2 View Cast的实现过程 22
3.3模拟结果及其分析 23
3.3.1轮缘初始方案模拟结果及其分析 24
3.3.2轮缘优化方案模拟结果及其分析 26
3.3.3轮毂初始方案模拟结果及其分析 30
3.3.4轮毂优化方案模拟结果及其分析 33
结论 38
参考文献 39
致谢 40 

摘要
 本文运用传统方法完成了对矿井天轮的铸造工艺方案设计，包括铸造方法、浇注位置、分型面的选择，各项铸造工艺参数的确定，以及浇注系统、冒口、冷铁的设计。根据天轮的结构特点及质量要求，对天轮轮毂、轮缘进行差时浇注。通过在天轮轮毂顶部设计两个保温冒口，在轮缘热节处上方放置冒口以及在轮毂厚大部位加冷铁，以期实现顺序凝固。建立铸件、浇注系统及冒口的三维实体模型，运用View Cast铸造模拟软件对天轮的凝固过程进行了计算。其结果显示，轮缘热节处、轮毂壁厚大部位最后凝固且产生缩孔缩松缺陷。根据模拟结果及分析，通过加大保温冒口尺寸、冷铁厚度，对铸造工艺进行优化。再次模拟的结果表明，优化工艺能将缺陷转移到冒口中，实现了顺序凝固，从而最大程度地消除了铸造缺陷，获得了合理的铸造工艺方案。

关键词：天轮；工艺优化；凝固过程；数值模拟
ABSTRACT
In this paper, the design of the casting process was obtained by traditional casting design method. The process consist of the choice of the casting, parting and casting position, the determination of casting parameters and the design of the gating system, risers and cold iron. According to the structural characteristics of sheave and quality requirements, the sheave wheels and rim be poured separately. In order to achieve progressive solidification, two heat risers were laid on the top of the wheel, some heat risers were placed on the top of the hot spot in the rim and cold iron was introduced near by the thick part of the wheel hub. Three-dimensional model of the casting was built and the solidification process of the sheave was simulated by use of View Cast. The results showed that the hot spot areas in the rim and thick part of the wheel hub freeze finally, and the shrinkage generated in these areas. According to the simulation results and analysis, the casting process program was optimized by means of increasing the size of riser and thickness of the cold iron. After simulated once again, the defects were transformed to risers. The defects were eliminated to the greatest extent and the progressive solidification was achieved. So the reasonable program of the casting process was obtained.

 Key Words: Sheave; Process optimization; Casting process; Numerical simulation