黄化机搅拌轴断裂成因及疲劳寿命  

Fracture causes and fatigue life of agitating shaft in xanthator

作　　者：谢纳冰 杨娜 瞿喜强 张春燕 王永兴[2] XIE Nabing;YANG Na;QU Xiqiang;ZHANG Chunyan;WANG Yongxing(College of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;College of Mechanical Engineering,Donghua University,Shanghai 201620,China;Hi-tech Heavy Industry Co.Ltd.,Zhengzhou 450001,China)

机构地区：[1]上海工程技术大学机械与汽车工程学院,上海201620 [2]东华大学机械工程学院,上海201620 [3]恒天重工股份有限公司,河南郑州450001

出　　处：《东华大学学报（自然科学版）》2021年第6期44-50,65,共8页Journal of Donghua University(Natural Science)

基　　金：国家重点研发计划资助(2017YFB1304000)。

摘　　要：黄化机搅拌轴是黏胶纤维原液生产中的关键部件,其主轴与支撑臂采用Q345钢焊接在一起,因搅拌过程中承受较大交变载荷,一定工作循环后焊接处的早期微裂纹会扩展成裂缝,致使搅拌轴过早失效返修。对黄化机搅拌轴进行有限元分析,并对焊接处易出现裂纹的部位进行缺陷检测,分析得出:应力集中和焊接缺陷是造成搅拌轴疲劳破坏或断裂失效的主要原因。采用容许应力幅法和裂纹扩展寿命估算法分别计算搅拌轴无、有初始焊接裂纹缺陷两种情况下的寿命,结果表明:在无初始焊接裂纹缺陷的情况下,搅拌轴寿命至少有10年;在有初始焊接裂纹缺陷的情况下,搅拌轴寿命仅有3~4年。此结果与实际情况具有很好的一致性。Agitating shaft in xanthator is the key component in the production of raw viscose fiber, and its main shaft and supporting arms are welded together with Q345 steel. Due to the large alternating load during mixing, the early microcracks in the welding will grow into cracks after a certain working cycle, causing premature failure of the agitating shaft for repair. Finite element analysis was carried out on the agitating shaft and defects of the parts prone to crack of the welding joint were detected. It shows that stress concentration and welding defects are the two main causes of fatigue damage or fracture failure of agitating shaft. The allowable stress amplitude method and the crack propagation life estimation method were used to calculate the life of the agitating shaft without and with initial welding crack defects. The results show that in the case of no initial welding crack defects, the life of agitating shaft is at least 10 years;in the case of initial welding crack defects, the life of the agitating shaft is only 3-4 years. The results are in good agreement with the actual situation.

关 键 词：黄化机搅拌轴 焊接应力 裂纹 有限元 疲劳寿命 

分 类 号：TG404[金属学及工艺—焊接] TS152.7[轻工技术与工程—纺织材料与纺织品设计]