PCM在油田站场埋地管道定位中的应用

Application of PCM in the Location of Buried Pipelines in Oilfield Stations

老区油田站场建设时间久,站内管道呈现网状密集埋地敷设状态,部分站内埋地管道运行时间长,已腐蚀老化,若发生泄漏,以往采用参考施工图纸沿着敷设路径现场开挖,才能准确判定漏点位置;现场开挖工程量大,抢修进度慢,并且现场破坏大,后续恢复工作量大,易造成其他非目标管道、电缆、设施的损坏。采用PCM(Pipeline Current Mapper,管中电流法,主要是测量管道中电流衰减梯度)设备可精确定位管道漏点位置,不开挖管道,在地面上追踪管道路由、探测埋深、判定破损位置等。PCM发射机对埋地管道加载一定强度电流信号,根据电磁感应原理,管道周围空间形成沿管道为中心的圆形磁场。地面上的PCM接收机内线圈会产生感应电流,先采用PCM回路接线法,用导线将PCM发射机与目标管道两端连接,形成“PCM发射机-连接导线-目标管道-连接导线-PCM发射机”的完整回路,接收机追踪电流信号可探测管道敷设路径及管道埋深,然后采用PCM常规接线法,形成“PCM发射机-连接导线-目标管道-大地-PCM发射机”的完整回路,定位管道泄漏位置。使用PCM设备施工工程量小,可避免破坏其他设施,加快抢修进度,迅速恢复生产,对油田安全稳产起到积极作用。

The construction time of the old oilfield station is long,and the pipelines in the station are laid in a dense network.Some buried pipes in the station are corroded and aged due to a long period of operation.In case of leakage,excavation on site along the laying path referring to the construction drawings is used in the past in order to accurately determine the location of the leak.However,the site excavation work is large,the repair progress is slow,the site damage is huge,and the subsequent restoration workload is tremendous.Besides,other non-target pipelines,cables,and facilities are at risk of being damaged by large-scale excavation.The leakage positions of the pipelines can be precisely located by the PCM equipment.Using PCM(abbreviation of Pipeline Current Mapper,which is mainly used to measure the current attenuation gradient in the pipeline)enables to trace the pipeline route,detect the depth of burial and determine the location of damage without excavating the pipeline underground.The PCM transmitter loading a buried pipe with a certain strength current signal will form a circular magnetic field along the center of the pipe in the space around the pipe according to the principle of electromagnetic induction.The coil inside the PCM receiver on the ground generates an induced current.The PCM circuit wiring method is adopted,using wires to connect the PCM transmitter to the two ends of the target pipe,forming a complete circuit of“PCM transmitter-connecting wire-target pipe-connecting wire-PCM transmitter”.The PCM receiver tracks the current signal to detect the pipeline laying path and pipeline burial depth.Then,the PCM conventional wiring method is adopted,forming a complete circuit of"PCM transmitter-connecting wire-target pipe-earth-PCM transmitter"to locate the leakage position of the pipe.This method has a small construction workload,avoids destroying other facilities,accelerates the repair progress,realizes rapid resumption of production,which plays a positive role in the safety and stability of oilfield production.