【作者】 王树奎；

【导师】 姜青河；

【作者基本信息】 山东大学 ， 材料工程， 2011， 硕士

【摘要】 226B系列柴油机是潍柴道依茨的主打产品,其产品质量直接关系到潍柴的企业形象和声誉。气缸盖是柴油机上重要部件之一,因此,气缸盖的性能要求比较高。同时,气缸盖结构比较复杂,铸件壁厚不均匀,最小壁厚只有5mm,质量不好控制,铸件毛坯综合废品率一直居高不下。分析废品原因,提出改进措施,提高铸件质量,是本课题的主要任务。本文通过对冷芯盒树脂砂、覆膜砂的发气量对呛气孔的影响及材料的发气速度对呛气孔的影响进行了大量的实验,发现影响气孔缺陷的主要因素不仅取决于芯子的发气量,其发气速度也是一个主要因素。当材料的发气量大时,如果其发气速度也较大,在铸件凝固前就已经全部释放完毕,则铸件也不易形成呛气孔缺陷。同时,还进行了内浇道的设置位置、浇注温度以及浇注速度对气孔缺陷的影响。结果发现采用开放式浇注系统及高温浇注对该系列气缸盖铸件防止气孔缺陷最好。另外,此铸件的芯子结构、芯头的排气对产生气孔缺陷有一定的影响。通过改进芯子的结构,使其顺利排气,对防止气孔缺陷也有良好的作用。在改进芯子结构的同时,对芯子的准确定位也进行了改进,解决了加工过程中时常出现的“偏芯子”、芯子烧结导致水腔不通的缺陷。更多还原

【Abstract】 226B diesel engine is the main product of WeiChai Deutz factory,and its quality has effects on the image and reputation of WeiChai.cylinder head is one of the important parts in a engine, so needs high capability。Cylinder head’s structure is complicated,the thickness of the casting wall is asymmetric,and the least thickness is only 5mm,so it is hard to control its quality and the reject rate is always high.The main work of this study is,ayalysing the reason of reject,putting forward the improving methods,and advancing the quality of castings.This article through to the resin sand of cold box cores, coated sand hair to choke the influence of porosity gas and materials of hair to choke porosity gas speed the influence of a large number of experimental, found the main factors of influence stomatal defects depends not only on the hair’s volume, the hair gas speed is also a major factor. When the hair of materials the decency, if the hair gas speed is larger also, in casting mold ago release all finished, the casting is formed not easily also choke stomatal defects.At the same time, also carried out the location of internal sprue, pouring temperature and casting speed on the influence of porosity defects. The results found that the open gating system and high temperature of the cylinder head such series casting prevent blow hole defects is best.In addition, the casting of the structure, core of the head’s exhaust to produce stomatal defects have certain effect. Through the improvement of s structure, make it smooth exhaust, to prevent blow hole defects as well as in effect. In the improvement of structure’s at the same time, it’s the accurate positioning also improved, and solve the processing process often appear "partial’s", sintering cause water chamber’s illogical defects.更多还原