某油井聚酮材料内衬油管失效分析  

Analysis on failure of polyketone lined tubing used in an oil well

作　　者：付小坤 田磊 FU Xiaokun;TIAN Lei(Northwest Oilfield Company,Sinopec,Urumqi 830011,China)

机构地区：[1]中石化西北油田分公司,新疆乌鲁木齐830011

出　　处：《电镀与涂饰》2024年第9期101-107,共7页Electroplating & Finishing

基　　金：国家科技重大专项“塔里木盆地碳酸盐岩油气田提高采收率关键技术示范工程”(2016ZX05053)。

摘　　要：[目的]塔河油田某油井的聚酮材料(POK)内衬TP110S油管现场应用105 d后发生腐蚀穿孔。[方法]通过形貌观察、化学成分测定、金相组织分析、硬度测试和拉伸试验,对油管基材进行失效分析,采用维卡软化温度和氧化诱导时间来评价POK内衬材料的理化性能和热学性能。[结果]内衬管基材穿孔失效的原因在于油管基材的Cr含量低,在高温环境下受CO_(2)和Cl-的协同腐蚀作用。POK内衬失效的原因是起管过程中受到井内高温至井口低温的温度变化影响,同时内衬材料脆化严重,导致部分POK内衬在起井过程中脱落,而温变产生的轴向拉伸应力和翻边预紧力导致个别内衬回缩明显。[结论]后期进一步规范油管上、卸扣作业过程,降低轴向应力,并改进POK材料,以提升内衬的抗温变能力。[Introduction]Corrosion perforation occurred after 105 days of field application of TP110S tubing lined with POK(polyketone)material in an oil well in Tahe Oilfield.[Method]The failure of tubing substrate was analyzed via morphology observation,chemical composition determination,metallographic structure analysis,hardness test,and tensile test.The physicochemical and thermal properties of POK lining material were evaluated by Vicat softening temperature and oxidation induction time.[Result]The reason for the perforation failure of the lining pipe substrate is that the Cr content of the tubing substrate is low,and it is subject to the synergistic corrosion of CO_(2) and Cl^(-)in a high temperature environment.The reason for the failure of POK lining is that it undergoes a temperature change from high temperature inside the well to low temperature at the wellhead during the pipe lifting process.At the same time,the lining material is seriously brittle,resulting in partial exfoliation of POK lining during the well lifting process,and the axial tensile stress and flanging preload caused by temperature change lead to obvious retraction of some linings.[Conclusion]In the future,the loading and unloading processes of tubing should be further standardized,the axial stress should be reduced,and the POK material needs to be modified to improve the temperature resistance of linings.

关 键 词：油管 内衬 聚酮 穿孔 腐蚀 

分 类 号：TE982[石油与天然气工程—石油机械设备]