油气管道内检测新技术与装备的开发及应用

油气管道内检测是保障油气管道安全的最有效的技术措施之一,而近年来出现的高碳钢、大管径、高压力、高流速油气管道对内检测技术与装备提出了新的挑战。为此,在调研电磁内检测新技术、极低频微弱瞬态信号检测新技术以及油气管道内检测新装备工程应用的基础上,基于电磁信号的主动发射与接收实现金属缺陷的检测,研发出电磁控阵检测器新技术与装备;基于杜芬混沌振子对含噪信号进行检测,实现对噪声中的极低频信号的检测,研发出极低频瞬态微弱信号检测新方法与装备,并开展了实际检测工程验证。研究结果表明:(1)研发的电磁控阵内检测新技术,利用直流励磁磁场和高频激励磁场协同作用的机理,仅用小信号激励即可实现响应的摄动效果;(2)引入采集信息成分的压缩采样,可突破内检测器的速度瓶颈,使电磁控阵检测器的检测速度达到创世界记录的8 m/s;(3)研发的基于混沌的极低频微弱瞬态信号检测新方法,可突破高速运动条件下内检测器管外跟踪定位过程中接收信号微弱且持续时间短暂的技术瓶颈,将微弱瞬态信号实时检测的信噪比降低到-10 dB以下。结论认为,该新装备的优越性能已经在实际运行的油气管道检测工程中得到了检验,将为国内主干油气管道的安全运行提供技术支撑和设备保障。

Development and application of new technologies and equipments for in-line pipeline inspection

In-line inspection is one of the most effective technical measures to ensure the safety of oil and gas pipelines. However, the extensive application of oil and gas pipelines of high-carbon steel, large diameter, high pressure and high flow rate in recent years brings about new challenges to in-line inspection. In this paper, we investigated the engineering application of new technologies and equipments, including the in-line inspection technology based on electrocmagnetic detector array, the extremely low frequency transient weak signal detection technology and new in-line inspection equipments. Then, the new technology and equipment of electrocmagnetic detector array were developed by applying the active emission and receiving of electromagnetic signal to inspect the metallic defects. Finally, noisy signals were inspected on the basis of Duffing chaotic oscillator, and thus the inspection of extremely low frequency signals in the noise was realized. In addition, the new method and equipment of extremely low frequency transient weak signal detection were developed and verified in actual inspection engineering. And the following research results were obtained. First, the in-line inspection technology based on electrocmagnetic detector array uses the synergetic effect between DC exciting magnetic field and high-frequency exciting magnetic field, so a perturbation response can be realized even by small signal excitation. Second, with the introduction of a novel compressive sampling of acquisition information composition, the speed bottleneck of in-line detector is broken through, and a new world record of the inspection speed of the electrocmagnetic detector array is set up, i.e., 8 m/s. Third, under the condition of high-speed movement, the received signals of in-line detector are weak and temporary while tracking and positioning outside the pipeline. And by virtue of the extremely low frequency transient weak signal detection method based on chaos, this technical bottleneck is broken through, and the signal-to-noise ratio (SNR) of transient weak signal in the process of real-time inspection is decreased below -10 dB. In conclusion, the superior performance of these new equipments has already been verified in the inspection engineering of in-service oil and gas pipelines. These research results will provide technical and equipment support for the safe operation of domestic main oil and gas pipelines.