Heat exchanger inspections

For 20 years Delta Test is doing heat exchanger inspections all over the world whereas the inspection by eddy current is of advantage both from the technical as well as economical point of view:

quick (= short times of standstill = low production downtimes)

reliable statements (damage indications from 20 % damage of wall thickness)

even bent tubes being situated inside may be inspected

exact documentation of the defect positions

the damage progress can be detected by repeat inspections (risk based analysis)

Inspections on site

Your heat exchangers will be inspected directly on site, in the unit or workshop by the most modern equipment. In the process we can survey all sections of the inspection object:

  • the free tube part
  • the tube plate regions
  • for U-bend objects: the bow regions

The high-performance sensor systems that are used for this purpose have been developed and manufactured by Delta Test.


Already during the inspection it is possible to receive, if requested, a preliminary documentation that can give you shortly a first overview over the condition of the inspection object.

In addition you will receive after finishing the inspection a complete documentation (for example. PDF, 1,9 MB) with indication of the conditions of the tubes inspection as well as damage progress analysis if requested, statement of defect positions over the tube length, plug plans and further analyses.

Your advantage:

  • always updated state of knowledge of the determined status
  • no waiting times for the arrival of a status report 
    = no further times of standstill

Of course, you will receive these documentations also in electronic version (PDF).

Advanced Possibilities of Documentation and Avoidance of Misinterpretation of Conventional Documentations

The exact documentation of the defect position enables the analyses of damage progress that are not possible with conventional measuring and documentation methods (see picture), since these still depend on the comparison of the maximum result of a tube.

In order to better demonstrate these facts that can partially be surveyed in a bad way, we revert to position-based defect result documentations.

In this case the length positions and results (right side of picture) refer to the outside tube layer (in the left part of the picture). The indications being each in the upper part describe the current results, the ones in the lower part the reference results of a previous inspection.

Thus this combined presentation allows a quick overview over the grade of the damage progress..

Should you have questions, suggetions or remarks regarding the inspection of heat exchangers by eddy current, please feel free to contact us directly!