光纤光栅传感网络在油气出地管内腐蚀监测的应用研究

Applied Research of Optical Fiber Sensor in Oil and Gas Pipe Corrosion Monitoring

油气管线内部腐蚀是导致管线失效的主要因素。针对这一问题,采用复用技术设计了一种基于光纤布拉格光栅的管线内腐蚀监测系统。该系统通过出地管线外表面的应力变化来确定内表面的腐蚀程度,利用7路光纤光栅传感器组成阵列式传感网络,通过温度补偿光栅实现温度补偿。实验表明,该系统测压精度较高,系统误差小于2.23%。用现场实际压力数据验证了系统的可行性与稳定性,该系统完全满足油气管线内部缺陷在线监测的要求。

Internal corrosion of oil and gas pipeline is one of the main factors leading to pipeline failure. Based on principle of the fiber Bragg grating strain sensor as well as the multiplexing technology, an on-line monitoring system based on optical fiber grating sensors is studied. The corrosion degree of the inner pipeline can be determined by the surface stress changes, and array sensor network using 7 channels of FBG sensor is set up in the monitoring system, through temperature compensation grating to realize temperature compensation. Experiments show that the system pressure measuring accuracy is high, with the system error less than 2.23%. The feasibility and stability of the system are validated by comparing the measurement results with the actual pressure from the scene of the production, meeting the requirements of internal corrosion online monitoring.