摘要
通过电火花数控线性切割机将弯头沿轴向剖开的实验方法,研究了Si O2颗粒对弯头冲蚀后的壁厚损失及微观形态,并分析了弯头磨损的分布与强度。结果表明,管流状态下颗粒对弯头的冲蚀主要集中于弯头外半圈,弯头外半圈质量损失与弯头内半圈质量损失比(定义为α)随着颗粒粒径增大而增大;小粒径颗粒对弯头冲蚀区域的影响较大而对壁厚损失影响相对较小,弯头(R=1.5D)最大冲蚀角为55°,此时颗粒对壁面的冲蚀作用最大,最容易造成磨损刺穿而导致弯头失效;冲蚀坑随着颗粒粒径增大而变大,但数量相对减少,颗粒对弯头的主要磨蚀机理是变形磨损,次要机理是低角度的微削磨损,它们的综合影响造成了弯头的穿孔刺漏。
Local erosion behavior of a square bend of 304SS steel induced by SiO2 sand blast was studied in terms of wall thickness loss along the band periphery and micro-morphology on the in- ner wall surface of the longitudinal section of a band after erosion test. The result shows that the erosion of the bend caused by sand particles is mainly concentrated on the outer half of the band and the ratio of the mass loss of the outer half to that of the inner half of a band, namely index α, increases with the increase of the particle size of the sand. Particles with small mean diameter have a greater effect on the dimension of eroded area, but less influence on the wall thickness loss. The maximum impact angle is 55° for a band with R=1.5D, where is apt to be suffered from perforation, leading to failure of the band. The size of pits induced by erosion increases but their quantity decreases with the increase of the sand particles size. The abrasion mechanism for particle impacting on the bend may mainly be ascribed to deformation wear, as well as to low angle microcutting wear, moreover, their comprehensive effect results in perforation and cut damage of the bend.
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2015年第5期437-443,共7页
Corrosion Science and Protection Technology
基金
国家油气重大专项项目(2011ZX05026-004)资助
关键词
弯头
局部冲蚀
气体携砂
变形磨损
bend, local erosion wear, pipe flow state, deformation wear
