高速轻烃泵轴断裂失效分析

Fracture Failure Analysis of A High-speed Light Hydrocarbon Pump Shaft

某输送轻烃的高速泵(LMV311-75-69SCSS)在间断运转2 333小时后泵轴发生了断裂事故。本文对失效泵轴的化学成分、硬度、金相组织、断口进行了检验和分析,结果发现该泵轴材质成分不均匀,材料组织内形成带状偏析,导致材料轴向强度不足;并详细剖析了此类非金属夹杂物对泵轴失效的影响因素。综合分析认定泵轴由于材料本身的缺陷导致了疲劳断裂。为避免泵轴再次发生断裂文中提出了相应的改进措施。

A high- speed light hydrocarbon pump （I_aMV311 - 75 - 69SCSS） shaft tiacture accident occurred in the 2 333 hours of intermit- tent operation of the process. The testing and analysis on the chemical composition, hardnes, microstructure, fracture of the failed shaft, it＇s shown that the main reason for failure in the shaft as a material inequality caused the banded segregation, leading to lack of axial strength. And a detailed ＇analysis of influencing factors of non - metaillic inclusions on the pump shaft failure is given in the paper. The final inspection found that fatigue fracture in the shaft resulted from the defects of the material itself. In order to avoid recttrrence improvement measures have been proposed.