Depending on the specific conditions in each individual case we offer two different systems:
  • DTS (Distributed Temperature Sensing). This technology operates on the basis of the difference in temperature between the transported medium and the surrounding environment. In the case of buried pipelines the fiber cable usually runs below (fluids) or above (gases)  the pipe. 
  • DAS (Distributed Acoustic Sensing): a very advanced photo-acoustic technology, in other words: locating a leak by "listening". Particularly applied for existing underground piping and in case there is little to no difference in temperature between the transported medium and the surrounding soil. An additional advantage is that already existing telecom cables running along the pipeline can be utilized. 
Both systems are capable of detecting a leak with an accuracy of 1 m over distances of up to 50kms.

A continuous high frequency light pulse of one specific wavelength is launched through one or more fiber cables attached to the pipeline. The reading unit analyses the so-called Brillouin-effect in the backscattered spectrum and translates this into the distributed strain- and stress behaviour over the full length of the pipeline. The measurements are automatically compensated for variations in temperature.

The system gives a reading at every meter which over a distance of e.g. 50kms results in the equivalent of not less than 50.000 sensors! And in addition to that the strain is measured as accurately as 20 microstrain (0,02mm/m) at any one point along the pipeline.

In densely populated areas new infrastructure often has to cross existing underground pipelines. In those cases the owner wants to be absolutely certain that deformations of his pipeline will not exceed allowable levels.

Depending on the specific case we offer a number of different techniques to monitor the pipeline during the construction activities. These techniques offer the possibility to continue the measurements after completion of the construction activities so as to monitor possible residual deformations caused by e.g. traffic loads.

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A unique photo-acoustic system that immediately warns for the threat of damage to the pipeline caused by digging activities, drilling and vandalism. Any activity generates acoustic energy ("noise") which is transduced to the silica molecules of a glass fiber. A reading unit continuously launches a high frequency light pulse through a fiber that is running parallel to the pipeline under observation and analyses the backscattered spectrum. Any activity as far as 10m from the pipeline is picked up by the fiber and is visible from the shift in the backscattered light. The system also shows the location of the activity with an accuracy of one to a couple of meters, even if the pipeline is up to 50kms long! And as every activity has its own acoustic "foot print", it is even possible to see what activity is taking place!

Already existing telecom fiber cables running parallel adjacent to the pipeline can sometimes be utilised which can lead to a considerable saving on capital investment.

In a broader sense DTS is not applied only for leak detection. Monitoring the distributed temperature profile of a pipeline or network can also serve as a process management tool. The advantages, when compared with traditional spot measurement, are evident.

Examples are crude oil pipelines where a local drop in temperature can cause precipitation of paraffin waxes or geothermal energy production applications.

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