Vibroacoustic Technology for Pig Tracking: Case Studies and Operational Insights for Permanent or Temporary Installations

Abstract The aim of this paper is to present case studies of pig tracking using Vibroacoustic Technology (VT), encompassing both temporary and permanent deployment on a pipeline. This system offers real-time tracking, even if installed mid-operation, providing accurate location information. Additionally, VT, already extensively deployed worldwide in Oil & Gas pipelines, yields valuable data that can be retrieved using this method. Originally developed for detecting and localizing leaks and third-party interference in pipelines, VT has demonstrated its capability to reliably identify the location of pigs as they traverse the pipeline and pinpoint the position of a stuck tool. Its movement inside the pipeline generates vibroacoustic waves that propagate for tens of kilometers at the speed of sound. It is possible to determine the source of the vibroacoustic waves, i.e., the pig, employing the time difference of arrival method. Sensor blocks can be installed at any hydraulic derivations along the pipeline or even in parallel with other instruments. These sensor blocks are equipped with batteries allowing for several days of autonomous operation and SIM cards for data transmission during temporary installations. In this work we show data from tracking campaigns in different pipelines. The first case study involves a 160 km offshore gas pipeline. Sensor blocks at the ends monitored the pig’s passage. Despite the distance, it was feasible to discern the precise moment welded joints were encountered. If it traverses a slightly deformed pipeline section, its location could be accurately determined. In the second case study, an onshore pipeline for refined products, though under VT surveillance for leaks, at the beginning of the inspection, the pig was not being monitored. When the control room detected the tool was stuck at an unknown location, VT specialists promptly analyzed available data, pinpointing its location within minutes. The last case study demonstrates VT’s effectiveness in monitoring two pigs within the pipeline. Introducing the second tool aimed to dislodge the first, highlighting the technology’s adaptability and valuable role in managing operational challenges within pipelines. Accurate pig tracking enables the pipeline operator to promptly address and effectively manage any challenges that might arise during the inspection. The versatility of VT as a pig tracking technology is showcased through cases involving both temporary and permanent installations. This includes instances where tracking was provided from the beginning of the operation and also situations where the stuck tool location was accurately determined after the operation had started.