对引起465Q缸体渗漏的原因进行了统计分析,结果发现:(1)浇注温度过高,容易引起晶粒粗大,而且还可能引起水套芯飘浮致使水套与回油道贯通,并引起渗漏；(2)孕育剂加入量增大,铸件缩松倾向增大,因而渗漏率增高；(3)Sr-Si孕育剂引起的渗漏率明显低于Si-Ca孕育剂.通过适当控制浇注温度,采用Sr-Si孕育剂并控制其加入量,恰当地选择激冷涂料和覆膜砂,使缸体渗漏率控制在1％以下.%A statistic analysis was conducted on the reasons causing leakage of cylinder block of 465Q engine. The results were as follows: (1 )Too high temperature often caused coarse crystal grain, and maybe caused floatation of the jacket core that maybe led to linking up of the water jacket with the oil spillover canal. Both of them maybe cause leakage; (2)The more inoculant amount,the more obvious the shrinkage tendency, and the higher the leakage rate; (3) the leakage rate caused by using Sr -Si inoculant was obviously lower than that caused by using Si -Ca inoculant. By properly controlling pouring temperature,adopting Sr-Si inoculant and controlling its adding amount,using proper chilling coating and resin-coated sand, the leakage rate of the cylinder block has been kept below 1%.
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