基于微试样的长时服役电厂高温管道力学性能研究  

Research on Mechanical Properties of High-temperature Pipelines of Power Plants in Long-time Service Based on Microsample

作　　者：包健[1] 左志全 丁浩然 彭剑[2,3] BAO Jian;ZUO Zhi-quan;DING Hao-ran;PENG Jian(National Chemical Equipment Quality Supervision and Inspection Center(Jiangsu),Special Equipment Safety Supervision Inspection Institute of Jiangsu Province,Zhangjiagang 215600,China;School of Mechanical Engineering and Rail Transit,Changzhou University,Changzhou 213164,China;Jiangsu Province Engineering Research Center of High-Level Energy and Power Equipment,Changzhou 213164,China)

机构地区：[1]江苏省特种设备安全监督检验研究院国家化工设备质量监督检验中心(江苏),江苏张家港215600 [2]常州大学机械与轨道交通学院,江苏常州213164 [3]江苏省能源动力高端装备工程研究中心,江苏常州213164

出　　处：《石油化工设备》2024年第5期1-6,共6页Petro-Chemical Equipment

基　　金：国家自然科学基金资助项目(52075050);江苏省高等学校基础科学(自然科学)研究重大项目(23KJA460002);江苏省特种设备安全监督检验研究院科技计划项目(KJ(Y)2023021)。

摘　　要：采用小冲孔试验方法、显微硬度试验方法、金相组织分析方法对高温、高压工况下(服役温度为260℃±20℃、工作压力为27 MPa)服役11.5万h后的损伤15CrMo耐热钢管道进行材料研究。小冲孔试验结果表明,与无损伤15CrMo耐热钢管道相比,损伤15CrMo耐热钢管道的小冲孔最大载荷和最大位移下降率分别为5.6%和5.89%。显微硬度分析结果表明,损伤15CrMo耐热钢管道内表面1 mm范围内存在8%的显微硬度升高,这与其内表面经历了长时的高温氧化损伤有关。金相组织分析结果表明,损伤15CrMo耐热钢管道内壁处由于高温氧化腐蚀,存在一定的晶粒脱落,易出现微裂纹,造成管道开裂。综合评价结果为,高温下长时服役对15CrMo耐热钢管道力学性能的损伤程度有限,材料能够保持良好的强度与塑性性能,未发生显著的力学性能退化与脆化,但管道内壁处的高温氧化损伤需引起关注,研究结果可为电厂高温管道的结构完整性评价提供参考。A small punch test method,microhardness method,and metallographic analysis method were employed to investigate the 15CrMo heat-resistant steel pipe material under conditions of high temperature and high pressure(260°C±20°C and 27 MPa)following a prolonged service period of 115000 hours.It was determined that the reduction rates of the maximum load and the maximum displacement of 15CrMo heat-resistant steel after long service were 5.6%and 5.89%,respectively.The microhardness analysis indicates that there is an 8%increase in microhardness within 1 mm of the inner surface,which is attributed to the long-term high-temperature oxidation damage experienced by the inner surface.Furthermore,microstructure analysis revealed that high-temperature oxidation corrosion resulted in the shedding of grains on the inner wall of the long-term serviced pipeline,which was prone to microcracks,ultimately leading to pipeline cracking.The results of this study indicate that the damage to 15CrMo heat-resistant steel at elevated temperatures over an extended service period is limited.The material retains its strength and plastic properties,with no significant deterioration in mechanical properties or embrittlement.However,the high-temperature oxidation damage observed in the inner wall of the pipeline should be a concern.This study provides a reference for the structural integrity evaluation of high-temperature pipelines in power plants.

关 键 词：管道 材料 力学性能 损伤 微试样 

分 类 号：TG142.12[一般工业技术—材料科学与工程] TQ055.8[金属学及工艺—金属材料]