降低长水口颈部应力的研究

Research on Decreasing Stress in the Neck of Long Nozzle

长水口颈部应力过大是其颈部开裂的主要原因。本文运用有限单元法 ,计算了长水口在工作状态下的热应力和振动引起的机械应力 ,发现造成颈部应力过大的主要原因是热应力 ;增加水口内壁不与钢水接触的长度可有效降低水口颈部应力。增加水口内壁不与钢水接触的长度可通过在水口内壁上部喷涂隔热材料或采用延伸扩大内孔直径的方式实现。

Too high stress in the neck of long nozzle is a major cause that results in fracture in the neck. In this paper, the thermal stress and mechanical stress were calculated by finite element method under the applied conditions and vibration normalized to the casting direction. Calculation results indicate that thermal stress is the main portion in total stress and increasing the none-contact length at the inner-upper surface of the nozzle can decrease the stress in the neck effectively. Increasing the none-contact length can be realized by installing heat insulating material at inner-upper surface or extending inner diameter of the nozzle.