摘要：In order to investigate the sand mold strength after the aeration sand filling-high pressure squeeze moldingprocess,a tree-dimentional(3D)numerical simulation was *** commercial finite element method(FEM)software ABAQUScombined with a revised Drucker-Prager/Cap model was used to simulate the squeeze compaction ***,the sand bulk density after the aeration sand filling process was tested by a specially designed experiment,which divided the whole sand bulk in the molding chamber into5x9regions and it was used as the input to simulate the squeeze *** the simulation process,the uniform modeling simulation and the patition modeling simulation methods were used a d the3D numercal simulation results were compared with correlative benchmark *** the3D numerica simulation results,it can be concluded that the uniform sand bulk density distribution can obtain a high quality sandmold and the revised Drncker-Pager/Cap model is suitable for handling the situation with the complex ***3D numerical simulation results can predict well the sand mold strength distribution and can be used as guidelines for the production practice.

摘要：针对面向现场装配的工艺信息完整准确表达与高效管理的应用需求,提出以三维装配过程模型为载体实现面向现场装配的产品装配工艺模型表达与管理方法。分析了面向现场装配的产品装配工艺信息变迁特点,明确了从产品预规划装配工艺信息向现场实际装配工艺信息的实例化映射规则;定义了三维装配过程模型与装配工艺信息数据集,并确定了工艺信息在该模型上的装配工艺基于模型定义(MBD)表达方案;利用装配工艺信息层级嵌套管理模式实现了对面向现场装配的产品装配工艺信息的有效管理,并构建了装配工艺管理器进行工艺信息的组织与存储。将上述方法集成于三维装配工艺设计系统中,并以创建某型减速器产品的三维装配工艺模型为例,验证了所提方法的有效性。

摘要：为实现曲率半径不低于5D(D为钢管直径)的热煨弯管的外根焊自动焊接,采用差速驱动、衬垫侧向伸缩、刚性与柔性转换等技术,研制了新型柔性带复合衬垫内对口器。针对单材质铜衬垫存在的焊缝渗铜、表面烧损或破损时不易修复且修复后精度降低,以及单材质烧结陶瓷衬垫使用时易因焊接高温反复影响而出现的表面烧损严重且不可修复、开裂、剥离、脱落等问题,设计了基于金属与陶瓷材料的、满足基体重复利用及陶瓷涂层再修复的复合衬垫。进行了柔性内对口器过弯管、爬坡、刚柔转换、管口组对等系列试验及工程现场测试。结果表明:柔性带复合衬垫内对口器具备对于曲率半径5 D热煨弯管的良好通过能力及30°爬坡能力,实现了直管与热煨弯管不同组合形式的精确组对、不大于30°坡度施工环境下的外根焊自动焊接与焊缝背面强制成形及刚性与柔性的适时转换;复合衬垫有效解决了单材质铜衬垫及烧结陶瓷衬垫易出现的问题,使用寿命、重复利用性及可修复性等综合性能更优。新型柔性带复合衬垫内对口器的研制成功提高了油气管道的焊接质量和施工效率,降低了施工成本。