混流式转轮局部处理技术与局部压应力区的优化  

Optimizing of compressive stress region by local treatment technologies on Francis runner

作　　者：程广福[1] 王辉亭[1] 姬书得[2] 方洪渊[3] 

机构地区：[1]哈尔滨大电机研究所水力发电设备国家重点实验室,哈尔滨150040 [2]沈阳航空工业学院航天技术研究所,沈阳110034 [3]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《焊接学报》2012年第8期97-100,118,共4页Transactions of The China Welding Institution

基　　金：国家973重点基础研究发展计划资助项目(2010CB736208)

摘　　要：焊接残余压应力的存在能够有效提高焊接结构的抗疲劳性能.在优化混流式转轮焊接工艺、实现转轮叶片出水边焊接接头熔合区附近易开裂区域压应力化的基础上,对局部加热及锤击处理对转轮易开裂区域的应力场分布的影响进行了数值模拟和真机试验测试分析.结果表明,采用局部加热和局部锤击的方法均可以对转轮易开裂区域的焊接残余应力场进行调控,优化转轮的局部压应力区,进一步提高转轮易开裂区域的残余压应力值,形成高压应力区,扩大压应力区范围,促进转轮易开裂区域压应力化的实现,有效的提高转轮的抗疲劳性能.The existing of residual compressive stress increases the fatigue resistance of welding structures.The local compressive stress was realized around the fusion boundary in the Francis turbine runner by optimizing the welding process,where fracture could easily occur.And the influence of local heating and peening on the stress field in the fracture-easily-occurred region of runner was simulated and measured based on the real runner.The results indicate that the stress field in the fracture-easily-occurred region of runner can be regulated and controlled by local heating and peening processes.And the local compressive stress region was optimized.The value of residual compressive stress in the fracture-easily-occurred region of runner was further improved,and high compressive stress region was formed,especially,the compressive stress region was expanded.These processes can promote the realization of local compressive stress in the fracture-easily-occurred region of Francis runner and effectively enhance the fatigue resistance of the runner.

关 键 词：混流式转轮 焊接残余应力 局部加热 锤击 局部压应力化 

分 类 号：TG404[金属学及工艺—焊接]