目的 研究在多相流动状态，尤其是段塞流动条件下，各种浓度的不同缓蚀剂对X70钢腐蚀的影响。方法 采用自制实验装置模拟起伏管路段塞流动条件，通过电子显微镜、挂片失重等方法，对挂片表面形貌、腐蚀速率进行分析，数值仿真了多相流动状态下缓蚀剂乙二醇对X70钢CO2腐蚀速率的影响。结果 自制实验装置的挂片表面形貌、挂片失重速度与真实环道实验相似。实验用缓蚀剂的质量浓度超过35 mg/L后，均匀腐蚀缓蚀效率提升明显，继续提高缓蚀剂的浓度，均匀腐蚀缓蚀效率变化不大。多相流动条件下，缓蚀剂对局部腐蚀的缓蚀效果不明显。仿真用缓蚀剂乙二醇的质量浓度达到250 mg/L后，缓蚀效率变化与实验结果类似。结论 自制实验装置可以模拟起伏管路内气液两相流动状态，实验结果可靠。缓蚀剂的最佳缓蚀效率存在临界浓度，小于临界值时，对挂片的缓蚀作用甚微，超过临界浓度时对挂片表面的腐蚀速率影响不大。段塞流动状态下，缓蚀剂的缓蚀作用仅针对挂片均匀腐蚀，对局部腐蚀影响不大，甚至会促进局部腐蚀的发展。

Objective To study the effect of corrosion inhibitors with various concentrations on X70 steel corrosion in multiphase flow state, especially under plug flow conditions. Methods The CO2 corrosion state of X70 steel under the condition of plug flow was simulated by using the self-made experimental device. The surface morphology and corrosion rate were observed and analyzed by electron microscopy and weight loss method. And numerical simulation was conducted to study the influence on CO2 corrosion rate of X70 steel of corrosion inhibitor glycol in the multiphase flow state. Results The coupon surface morphology and weightlessness rate of using homemade experimental apparatus was similar with using real ring test. The uniform corrosion inhibition efficiency was obviously improved when the corrosion inhibitor concentration was more than 35 mg/L. If corrosion inhibitor concentration was continuously improved, uniform corrosion inhibition efficiency would have no big change. Under multiphase flow conditions, effect of corrosion inhibitor on local corrosion was not obvious. The simulation results were similar to the experimental results when the corrosion inhibitor concentration of ethylene glycol was of up to 250 mg/L. Conclusion Homemade experimental apparatus can simulate gas-liquid two phase flow in the rolling pipeline, and the experimental results are reliable. There is critical concentration for best corrosion inhibitor efficiency. If it is less than the critical value, the corrosion inhibitor will have little effect on metal; if it is more than the critical concentration, the changing of the corrosion rate will be small. Under plug flow conditions, the corrosion inhibitor has impact on uniform corrosion only, but has small impact on local corrosion and even promotes the development of the local corrosion.