循环流化床锅炉埋管泄漏原因分析  

Analysis on Leakage Reasons of Buried Pipes in a Circulating Fluidized Bed Boiler

作　　者：钱锟 QIAN Kun(Shanghai Baoye Engineering Technology Corp., Ltd., Shanghai 200941, China)

机构地区：[1]上海宝冶工程技术有限公司,上海200941

出　　处：《理化检验（物理分册）》2017年第4期268-272,共5页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：采用宏观分析、化学成分分析、金相分析、硬度测试、断口分析、X射线衍射等方法,对某循环流化床锅炉埋管在使用约1.1×10~4 h后出现泄漏的原因进行了分析。结果表明:埋管下弯管段水垢过厚,导致其外壁长期处于超温状态,产生珠光体球化及脱碳现象,严重降低了管壁的强度和硬度;同时,炉膛内介质对下弯管段外壁冲刷作用较大,加大了管壁减薄速率;以上原因导致埋管下弯管段出现早期泄漏失效。Means such as macro examination, chemical composition analysis, metallographic analysis, hardness test, fracture maalysis and XRD analysis were used to analyze the leakage reasons of the buried pipes in a circulating fluidized bed boiler after use of 1.1 × 10^4 b. The results show that the limescale layer at lower curved section was very thick, which caused long-time overheating of outer wall of the buried pipes. So pearlite spheroidization and deearburization phenomenon occurred, and the strength and hardness of the pipe wall seriously decreased. At the same time, the medium in the hearth had larger flushing action to outer wall of the buried pipes at the lower curved section, which accelerated the wall thickness thinning rate here. The above reasons led to the early leakage failure of the buried pipes at the lower curved section.

关 键 词：循环流化床 埋管 水垢 珠光体球化 脱碳 冲刷 泄漏 

分 类 号：TG146.1[一般工业技术—材料科学与工程] TG454[金属学及工艺—金属材料]