Thermal Imaging from Thermal Survey Ltd

Thermal Survey’s remote sensing team has, in response to the water industry’s growing leakage problem, developed a thermal imaging service based around the needs of this particular market.

The pipeline survey not only provides data on possible leakage points but also on the status of the wayleave, showing up any ground disturbance or building works over the pipeline.

These surveys generally fall into two categories.

 
Low level surveys of the known course of a pipeline over open country. By carrying out a low level survey, extremely high resolution images may be produced which are invaluable to leakage engineers for defect identification and prioritisation.

Higher level surveys of rural countryside where pipes lie but whose exact position is not known. These are usually flown at 2,000 feet, which gives a good balance between resolution and flying time (and therefore cost). The pipe or pipe bed is usually visible around 60% of the time depending on ground composition & cover.

It is important to remember that although Infra-red equipment is a valuable diagnostic tool, it merely provides a ‘map’ of radiant energy. It cannot for example give a definitive answer to why a particular area is at a certain temperature or radiating at a certain emissivity, although skilled interpretation by Thermal Survey staff can be a valuable source of advice in this area.

High resolution thermal imaging has proven to be a versatile technique for identifying pipeline (or reservoir) anomalies in rural areas in addition to identifying environmental effects such as discharge into watercourses.

The pipeline is flown in a series of tracks, the number of which depend on the pipeline route. Each of these is related by an on-screen time stamp to the real time video record.

This map is then marked with any thermal anomalies noted and used as the basis for discussions with pipeline management staff who are familiar with possible valid causes for many of the anomalies (such as pipe furniture for example).

This is often provided in parallel with a tabulated list of anomalies, their track number, time/date stamp, classification of priority (high. medium, low) and appropriate comment.

Feedback from pipeline teams indicates that the sensitivity is sufficient to detect damp patches smaller than those which would emanate from a weeping joint. Considerable man hours are expended in analysing and tabulating the data.

Carrying out an aerial survey of rural trunk water distribution can bring numerous benefits, not only are there the immediate engineering benefits, but also the opportunity for positive PR coverage.

Thermal Survey have a wealth of experience in assisting organisations make the most of their survey data by holding exhibitions, seminars and training sessions.