彭以超,王贤明,干建丽,赵炜炜
PENG Yichao,WANG Xianming,GAN Jianli,ZHAO Weiwei

• 1:浙江浙能技术研究院有限公司
• 2:浙能北海水力发电有限公司

摘要(Abstract)：

以断裂的筒形阀接力器滚珠丝杆为研究对象,对丝杆断裂部位进行了包括化学成分、表面渗碳情况、不同部位的金相组织、断口裂纹源及扩展路径、力学性能、接力器运行状态等一系列分析,进而综合讨论滚珠丝杆的失效机理。发现造成滚珠丝杆发生弯曲断裂的直接原因是接力器下腔的压缩空气未排除干净,压缩空气的瞬间爆破造成瞬间反馈丝杆轴向窜动量增大,端部主、从动齿轮耦合咬死,使得丝杆瞬间无法旋转,在轴向的压力和扭矩下丝杆发生弯曲和断裂。另外,滚珠丝杆通过渗碳来增加表层硬度,表层硬度最高可达743 HV,组织为针状马氏体,表层高硬度造成丝杆脆性较大,脆性表层容易萌生裂纹并迅速扩展发生断裂。
By research on the fractured servomotor ball screw of a cylindrical valve, the paper analyzes the fracture in terms of chemical composition, case carburization, and metallographic structures, crack initiation,propagation path, mechanical property of different parts and servomotor operation performance; furthermore,it discusses failure mechanism of the ball screw. The final result shows that the fracture was caused by the left compressed air in the lower servomotor cavity. The instantaneous blast of compressed air caused sudden axial displacement increase of the screw and final locking of the driving and driven wheels on the screw end, so the screw bended and broke finally due to torque and axial pressure. What's more, the ball screw is carburized to increase the surface hardness, which is up to 743 HV and the structure is needle-shaped martensite.The great surface harness results in screw brittleness, and the brittle surface may easily crack and fracture with its propagation.

关键词(KeyWords)： 筒形阀;接力器;滚珠丝杆;断裂;失效分析
cylindrical valve;servomotor;ball screw;fracture;failure analysis

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 彭以超,王贤明,干建丽,赵炜炜
PENG Yichao,WANG Xianming,GAN Jianli,ZHAO Weiwei

DOI: 10.19585/j.zjdl.2016.12.007

参考文献(References)：

• [1]吴旭明,陈荣洲.筒形阀在滩坑水电站中的应用[J].中国水能及电气化,2010(1):55-58.
• [2]梁玉福.水轮机筒形阀[J].红水河,2003,22(2):54-57.
• [3]沈芳,张承俊,苏纪成,等.数字缸在溪洛渡电站筒形阀控制系统中的应用[J].水电站机电技术,2014,37(5):45-47.
• [4]甘楠,时天富.数字缸在水轮机筒形阀电液同步控制系统中的应用[J].水力发电,2011,37(8):59-61.
• [5]钟培道.断裂失效分析[J].理化检验-物理分册,2005,41(7):375-378.
• [6]孙胜伟,宋亚虎,刘铁山,等.20Cr Mn Mo钢渗碳齿轮磨削裂纹成因分析[J].理化检验-物理分册,2016,52(2):117-120.
• [7]刘永飞,王平怀,党恩,等.20Cr Ni Mo钢零件渗碳表层淬火开裂原因分析[J].理化检验-物理分册,2014,50(3):229-231.
• [8]徐令令.高过载工况下滚珠丝杠副的失效分析与性能试验研究[D].南京:南京理工大学,2014.
• [9]柳胜.精密滚珠丝杠副强过载下承载与破坏机理研究[D].南京:南京理工大学,2011.
• [10]东方电气集团东方电机有限公司.一种筒形阀接力器腔体结构及筒形阀接力器:CN,204573285 U[P].2015-08-19.