我厂是年产铸件2000吨以上的专业铸造厂,生产和各类曲轴铸件占全年总产品的70％左右。在曲轴生产中主要的铸造缺陷之一是曲轴鼓形铸孔变形和出现毛刺。 1 问题的提出曲轴的铸孔都是外小内大呈鼓形。长期以来,我厂采用传统的桐油制芯工艺进行生产。由于桐油砂湿态强度低,制芯操作时往往对开芯盒的接缝处紧实不 Our factory is an annual output of casting more than 2,000 tons of professional foundry, production and all kinds of crankshaft castings accounted for about 70% of the total product. One of the major casting defects in crankshaft production is the distortion and burr of the crankshaft drum bores. 1 questions raised Crankshaft casting holes are large and small within the drum-shaped. For a long time, our factory uses the traditional tung oil core production process. Because tung sand wet strength is low, the core operation is often open core box seams do not firm