DAS(Distributed Acoustic Sensing) system connects cables with DAS engine devices, plays a role of sensor and measure sound vibration when the situations generated in overall detection sections have an impact on censor cables.

This system enters disturbing laser pulse into optic cables and detect Rayleigh rear scattering light in the optic fiber so that the information of each interference spots (situation requiring detection) included will be acquired. (C-OTDR).
Detected sound signals are databased through digitizing and filtering process with high-performance computer and the provision of intuitive data is available from graphicalizing based on the time and space (distance)

Factors impacting on overall performance and alarming ability of DAS system

  • Kinds of sensor cable
  • Condition of distribution of sensor cables and status
  • Soil condition while underground pavement
  • Condition of noise from surrounding environment

At the actual application site, the detection of various events is influenced by the same conditions as described above and other ones.
After installing DTS system at the site, optimal solutions are provided by reflecting the variables on relevant project environments at most through additional engineering process including algorism analysis. A calibration work is to be gone through in order to analyze temperature pattern by sections, improve overall performance and, minimize mistakes in alarming.
The circumstances and unique values of all the sites are different and it is necessary for optimizing process for event detection values on a regular basis after initial installation and calibration work. (for example: it may be necessary upon changes in soil and environmental conditions)

Application plan

  • Pipelines
    – TPI(Third Party Intrusion) : 3rd party intervention- Drilling, perforating work by people and machine and theft (fmax < 500Hz)
    – Leak Detection : Leakage of high /low voltage gas, fluid, flange and leakage at the entrance of pipe (fmax < 1kHz)
    – Pipeline Inspection Guage(PIG) tracking Leak (fmax < 500Hz)
  • Power Cables
    – TPI land : 3rd party intervention- Drilling, perforating work by people and machine and theft
    – TPI marine : Intervention of anchor (fmax < 500Hz)
    – Pipeline Inspection Guage(PIG) Tracking Leak (fmax < 500Hz)
  • Others
    – Train related tracking field (including derailment, full length and line condition)
    – Security of borderline (including fence) (such as invasion and cut)
    – Conveyor belt