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           Pipelines & Tanks


           - TOFD

           - Phased Array

           - MAPSCAN

         - T-Scan



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In industry, Corrosion, Cracking and HIC (Hydrogen Induced Cracking)/HTHA (High Temperature Hydrogen Attack) cause enormous losses, and yearly costs millions in terms of component replacements and product losses. Calamities can form a serious threat for safety and environment.



TOFD is one of the most advanced, accurate and reliable methods for the crack detection and sizing. Mainly TOFD can be combined with a set of methods and techniques to detect cracking and specially HIC/HTHA. To read more about TOFD technique, please click here.


Phased Array


Phased Array is also one of the advanced NDT methods now is being popular. Now a days many advances has been achieved in this technique. Phased array is capable to detect many different types of defects in weld and base material and also can be used for the pre- and in-service inspection. To find our more about this method click here.



For timely detection of possible dangers, mapping on pipes, pressure vessels, reactors and tanks, the RTD MAPSCAN is the simple solution to choose.
The system combines flexibility of manual ultrasonic inspection with the capabilities of mechanized systems to coherently display results in mapping form.


Transducer position

Corrosion and HIC/HTHA mapping would normally require a mechanized ultrasonic system, because such systems automatically provide for the
proper combination of measured wall thickness values with corresponding
transducer positions. In RTD MAPSCAN however this need is met
in an intelligent way, thereby maintaining the advantages of manual

Transducer on a string

The (manually scanned) transducer is
connected with a special encoder device
by means of a thin nylon string; string
movements (length and angle) are
measured and translated into a rectangular
coordinate system. Because the inspection
is carried out by hand, RTD MAPSCAN
application is flexible, with a minimum of
time and costs involved.


- Small dimensions and weight
- Area scanned 500 x 250 mm
- Very high resolution scans possible
- Maximum wall thickness 125 mm
- Qualitative detection of High Temperature

   Hydrogen Attack
- Coated objects are fully inspectable
- Off-line presentation of images
- Distance to encoder max. 1 meter
- Data is digitally stored

With RTD MAPSCAN the advantages of manual ultrasonic scanning are combined with those of a mechanized inspection in an intelligent way. Therefore, RTD MAPSCAN is the solution to choose for fast corrosion
mapping and for periodic integrity monitoring. Unnecessary costs and calamities can thus be avoided.


AUT Mapping (T-Scan)


Corrosion and High Temperature Hydrogen Attack (HIC/HTHA) on hard to reach places like shells of storage tanks, columns and pressure vessels cause a lot of problems in the petrochemical industry. Detection can be impossible or very expensive, when using conventional techniques. Sometimes the object has to be taken out of service or scaffolding has to be put up for access to the area under investigation. The T-scan method has been developed to inspect the wall for Corrosion and HIC/HTHA on hard-to-reach areas. With the system Corrosion or HIC/HTHA can be detected on time and appropriate action can be taken.

Benefit to the client

Through the X and Y mapping the exact
position of the Corrosion or Hydrogen
Attack can be established, even in hard-to-reach
places without the need to put up
scaffolding or use rope-access. Based on
the results a fitness for service study can
be carried out to establish the integrity of the
object under inspection.


Through the P-scan IV ultrasonic equipment
and the AWS-5D manipulator large areas can
be scanned automatically.
To this end the manipulator is fitted with an
ultrasonic probe that is moved over a slider
bar. The scanner with the magnet wheels has
encoders that allow for a position measurement
in the X and Y direction. The measured wall
thicknesses are registered in a two-dimensional
color plot

Data representation

The data from the inspected object wall is
digitally stored and reported. A top view is
automatically being generated by software,
with the different indications plotted in different
colors. Corroded areas and areas damaged by
Hydrogen Attack can be easily recognized. At
the same time a cross-sectional view is
generated in the X and Y direction.


- No maximum wall thickness
- Minimum wall thickness 2 mm
- Very high resolution scans possible
- Maximum scanning height 40 meters
- Piping can be scanned from 3"
- Coated objects are fully inspectable
- Built-in water supply for probe
- Maximum width of one track is 75 cm
- Fast B-scan also possible