大型挖掘机斗杆液压缸活塞杆断裂分析与改善  

Piston Rod Fracture Analysis and Improvement of Large Excavator Bucket Rod Cylinder

作　　者：刘大昌 徐超 曹赛琪 LIU Da-chang;XU Chao;CAO Sai-qi(Transmission Division,Sany Heavy Industry Co.,Ltd.,Loudi 417000,China)

机构地区：[1]三一重工股份有限公司传动事业部,湖南娄底417000

出　　处：《液压气动与密封》2024年第6期104-108,共5页Hydraulics Pneumatics & Seals

摘　　要：大型挖掘机斗杆液压缸在使用过程中发生活塞杆断裂,通过对工况的分析,断口的宏观、微观分析,化学成分分析,力学性能分析,金相组织、硬度分析,缓冲压力测试,得出:破碎锤某特殊工况的斗杆液压缸缓冲压力远高于平常配置铲斗的缓冲压力,在高缓冲压力的冲击下,应力相对较高的螺纹起始牙位置冲击出微裂纹,继而裂纹扩展到整个活塞杆横截面,最终发生杆断裂。分析得出:通过改善破碎锤工况的缓冲压力,可以有效解决此活塞杆断裂,为后续大型挖掘机液压缸设计测试提供了借鉴与参考。The piston rod fracture occurs during the use of the bucket cylinder of a large excavator.Through the analysis of working conditions,the macro and micro analysis of the fracture,chemical composition analysis,mechanical property analysis,metallographic structure,hardness analysis and buffer pressure test,the conclusion is drawn:The buffer pressure of the bucket rod cylinder in a special working condition of the crushing hammer is much higher than that of the usual bucket.Under the impact of the high buffer pressure,micro-cracks occur at the initial teeth of the thread with relatively high stress,and then the cracks extend to the entire cross section of the piston rod,and finally the rod breaks.Through analysis,it is concluded that by improving the buffer pressure in the working condition of the crushing hammer,It can effectively solve the piston rod fracture and provide guidance and reference for the subsequent design and test of large excavation oil cylinder.

关 键 词：活塞杆 疲劳断裂 缓冲压力 分析 

分 类 号：TH137[机械工程—机械制造及自动化]