2205DSS连续油管的适用性研究

Suitability of 2205DSS Coiled Tubing

当连续油管用于井下作业时,管体需承受高压、强酸的井下环境以及反复缠绕、弯扭挤压等复杂载荷,因而连续油管的材料不仅应具有较好的强度和韧性,还应具有较好的耐腐蚀和抗疲劳性能。对2205DSS连续油管和传统碳钢连续油管进行了化学分析、拉伸、压扁、扩口、硬度、疲劳性能以及耐腐蚀性的对比试验。试验结果表明,2205DSS连续油管比碳钢连续油管具有更优异的抗腐蚀性能,强度可达到CT90级或CT100级连续油管的强度值,且双相不锈钢材质金相组织相对稳定,焊接热影响区的面积比碳钢连续油管的焊接热影响区的面积小,具有更为优异的疲劳性能,但2205DSS材质比碳钢成本高,生产时所消耗的能量较大,在应用方面仍存有一定的局限性。

In the common application of coiled tubing in downhole operation,the tube body needs to bear high pressure,strong acid downhole environment and complex loads such as repeated winding,bending and torsion extrusion,so the coiled tubing material should have not only good strength and toughness,but also good corrosion and fatigue resistance.In this paper,the chemical analysis,tensile,flattening,flaring,hardness,fatigue performance and corrosion resistance of 2205DSS coiled tubing and traditional carbon steel coiled tubing are compared by using the necessary test equipment.The experiment results show that 2205DSS coiled tubing,with superior corrosion resistance compared to carbon steel coiled tubing,can meet the strength requirements of CT90 and CT100.In addition,the microstructure of duplex stainless steel is relatively stable.Compared with carbon steel coiled tubing,it has a narrower heat-affected zone and better fatigue resistance.However,the material of 2205DSS has a slightly higher cost,greater energy consumption during production,so there are still some limitations in its application.