论文部分内容阅读
在生产水压机底座、横梁,电铲履带架,以及双辐极大型轮型铸件时,在铸件壁板交接的热节处常易产生裂纹。由于这类铸件的裂纹不易焊补有时不允许焊补,常常导致铸件报废,造成经济损失。以往防止裂纹的手段是:1)沿热节处放置外冷铁,2)在型芯上沿与热节垂直的方向割加强筋。但是这类方法或因操作费工,或由于在硬化后的型芯上割筋会造成铸件角隅处粘砂,生产中常不喜欢采用。而且这类方法有时还不能确实可靠地防止裂纹产生。多年来的生产实践经验表明,采用鱼刺形内冷铁是防止铸钢作热节处出现裂纹的一种简便且更为有效的方法。
In the production of hydraulic base, beams, shovel shovel rack, and double-spoke large wheel castings, castings at the junction of the hot section often easy to crack. Because of this type of casting is not easy to repair welding crack sometimes does not allow welding, often lead to scrapped castings, resulting in economic losses. In the past, the means to prevent cracking were: 1) placing cold iron along the hot joints, and 2) cutting the ribs along the core perpendicular to the hot joints. However, such methods are often not preferred for use in production, either because of labor costs or because of the tendency to stick sand on the corner of the hardened core. And sometimes such methods do not reliably prevent crack formation. Years of production practice have shown that the use of fish-shaped internal cooling chill iron is to prevent the hot section of steel cracks occur at a simple and more effective method.