4A缸体的工艺设计及优化

Process Design Optimization of 4A Cylinder Block

介绍了4A缸体铸件结构及原生产工艺,并针对原工艺存在的缺陷问题,采用精益理念,从生产布局到模具设计进行优化,重新设计工艺,避免了跨区域作业,减少了砂芯的转运。工艺优化过程中,从主体芯的生产、芯砂种类及涂料等方面入手,将砂芯易烧结部位割离,选用粒度140/70目的覆膜砂,并浸涂专用的防烧结涂料解决易烧结问题;对主体芯射不实的部位增加射嘴,增加排气,减短油孔芯头,解决砂芯疏松问题。经过生产调试和批量生产,综合废品率从24.6%降至6.28%,又经过近2年的过程控制优化,废品率可以控制在5%以下。

The structure and former production process of 4A cylinder block was introduced,and in order to solve the defect problem existing with former process,adopting lean concept,conducted optimization from production layout to pattern toolings design,redesign the process,avoided cross-regional operations,reduced sand cores transport.The process optimization began with main body cores production,core sand sorts and coating,the location easy to be sintered was cut off,coated sand with grain size of 140/70 mesh was chosen,and special anti-sintering coating was dipped to solve problem of easy to be sintered.After production debugging and mass production,the comprehensive waste rate decreased from 24.6%to 6.28%,and further more after 2 years process controlling optimization,the waste rate could be controlled less than 5%.