摘要
通过断口分析、显微组织观察、硬度分析和力学性能试验对发生断裂的喷焊光杆的断裂原因进行了分析。分析结果表明,光杆杆体采用30CrMo合金钢制造,杆体的理化性能符合SY/T 5029—2013标准的要求,但光杆喷焊层的硬度低于SY/T 5029—2013标准的要求。由于喷焊层下杆体表面硬度较低和喷焊层厚度较薄,疲劳裂纹在喷焊层与杆体外表面的界面处萌生,并在使用中逐渐扩展,从而导致喷焊光杆发生了早期疲劳断裂。建议改进喷焊光杆热处理工艺和喷焊工艺,预防此类失效事故的发生。
The fracture reason of a polished rod with spray welding layer was analyzed by fracture analysis,microstructure observation,hardness analysis and mechanical property testing.The results show that the polished rod body is made of 30CrMo alloy steel.The mechanical properties of the rod body meet the standard of SY/T 5029—2013,but the hardness of the spray welding layer of the polished rod is significantly lower than the requirement of SY/T 5029—2013.The fatigue crack initiation can be accelerated at the interface between the spray welding layer and outer surface of the rod body because of a low hardness at the surface of rod body and thin thickness of the spray welding layer,the corrosion fatigue life of the polished rod was clearly reduced.It is suggested to improve the heat treatment process and spray welding process of polished rod to prevent the occurrence of such failures.
作者
杨琦
王尚卫
程飞
曹峰
王军利
甘江
赵元雷
李德君
YANG Qi;WANG Shangwei;CHENG Fei;CAO Feng;WANG Junli;GAN Jiang;ZHAO Yuanlei;LI Dejun(CNPC Tubular Goods Research Institute,Xi′an,Shaanxi 710077,China;Oil and Gas Technology Research Institute of PetroChina Changqing Oilfield Company,Xi′an,Shaanxi 710021,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,PetroChina Changqing Oilfield Company,Xi′an,Shaanxi 710022,China;Oil Production Plant NO.8 of PetroChina Changqing Oilfield Company,Xi′an,Shaanxi 710016,China;Shanxi Lanyan Coalbed Methane Company Limited,Jincheng,Shanxi 048204,China)
出处
《石油管材与仪器》
2022年第6期70-73,共4页
Petroleum Tubular Goods & Instruments
关键词
光杆
失效分析
疲劳断裂
喷焊
polished rod
failure analysis
fatigue fracture
spray welding
