摘要
为了判断发生“飞温”事故后的丙烯净化器能否继续安全使用,进行了系列检验,采用具有早期缺陷诊断功能的金属磁记忆技术,并应用强度理论对容器进行了安全评价:由于在役容器无法实行力学性能的直接检测,分别进行了硬度、金相、超声探伤及1．28倍的水压试验,同时进行应力测试及金属磁记忆跟踪检测发现,过烧部位晶粒变大、珠光体组织有明显聚集;硬度值比正常母材区降低近30％;磁记忆信号随工作应力增加出现异常．为监督其变化趋势,于容器运行一个月后的卸压状况下进行了第2次跟踪检测．结果表明,容器过烧后强度储备下降,在正常工作压力2．5 MPa下,Tresca应力安全系数约为1．9;过烧区存在多处应力集中,运行一个月后应力集中程度略有增加．
A temperature-jump accident occurred because of wrong operations for a propylene purifier in a chemical plant. To make sure if the purifier can be operated safely after the temperature jump, a series of testing and strength safety evaluation were implemented. Because the direct testing of mechanical properties of the purifier was not available, hardness measuring, metallographic examinations, ultrasonic inspection and hydro-test were performed, respectively. Simultaneously with hydro-test, stress measuring and metal magnetic memory nondestructive testing （MMMT） which can describe early defect were applied. The results showed that, due to temperature-jump, in the burnt area the grain size became larger, the colony of pearlite structures occurred, the hardness dropped by 30% and magnetic signal became abnormal as the stress increased. In order to monitor the magnetic change, the second MMMT was performed after the purifier had worked for a month. It is indicated that the reserve strength declined, the Tresca stress safety factor with normal working pressure of 2.5 MPa was about 1.92, several stress concentration existed in the burnt area and the level of stress concentration increased a month later.
出处
《北京工业大学学报》
EI
CAS
CSCD
北大核心
2007年第2期119-125,共7页
Journal of Beijing University of Technology
关键词
应力分析
无损检测
应力集中
磁记忆
丙烯净化器
stress analysis
nondestructive testing
stress concentration
metal magnetic memory testing
propylene purifier
作者简介
张亦良（1955-）．女。北京人，教授．
