一、问题的提出我厂采用卧式离心浇注机成筒浇铸的方法,生产蒸汽机车汽缸和汽室的涨圈。生产中,一度在铸件的内孔处出现微观夹杂。这种夹杂,用电热检查可见到该处电阻增大,X光照影呈云雾状,其深度距自由表面10～15毫米,并和自由表面相通。分析生产这种缺陷的原因时,考虑到:由于铸型的转速偏低,离心力不足,未能使较轻的熔渣浮入自由表面。因此,对一台离心浇注机提高转速,进行生产实践,观察效果。二、生产条件和取样方法汽缸涨圈的外径范围在555～675毫米之间,壁厚分35毫米和37.5毫米两种。由于滚筒外径不同,在同一浇注机上滚筒的转速 First, the issue put forward I plant horizontal centrifugal casting machine into a tube casting method, the production of steam locomotive cylinder and steam chamber ring. Production, once in the casting hole at the microscopic inclusions. This inclusion, with electric heating can be seen where the resistance increases, X-ray was cloud-like, its depth from the free surface of 10 to 15 mm, and the free surface of the same. Analysis of the reasons for the production of such defects, taking into account: due to the mold speed is low, insufficient centrifugal force, failed to float the lighter slag free surface. Therefore, a centrifugal casting machine to increase speed, production practices, observe the effect. Second, the production conditions and sampling methods Cylinder up ring diameter range of 555 ~ 675 mm, wall thickness of 35 mm and 37.5 mm two. Due to different drum diameter, drum speed in the same casting machine