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FIGURE 1: Calibrating the scanner FIGURE 2: Defects visible in Pipecheck software

Before a P/11 inspection is conducted, To become a qualified mechanical This is due to the technician needing
the wall thickness (NWT) must first damage technician, the technician physical contact with the pipeline.
be obtained using ultrasonic must complete a four-day course and The technician has to do the best
equipment accurate to 0.1mm. be mentored on three occasions when they can with the apparatus available
The technician should then measure conducting the assessment. The to assess the defect in close proximity
the peak depth and the axial length of assessment can be undertaken to to one of the above obstacles and will
the defect. When conducting the assess numerous different types of always classify the defect as being
inspection, the technician will also defects including: gauges, cracks, more severe than it may be.
inspect visually for any cracking dents, stress cracking corrosion, This can result in a change in
present; if there is a possibility of general corrosion, pitting corrosion, remedial works and an increase in
cracking, the technician must conduct alternating current (AC) corrosion, costs, which may not be necessary.
a magnetic partial inspection (MPI) as spalling, arc strikes, laps or slivers (T/ The 3D scanner, on the other hand,
per T/SP/NDT/2. PM/P/11 – February 2012). does not rely on physical contact with
Once all the information necessary The Creaform HandySCAN 3D the pipeline, therefore can assess
has been obtained, the technician will handheld scanner and accompanying defects with the same degree of
then conduct a full P/11 inspection of Pipecheck software is a new and accuracy wherever their location.
the defected area, this inspection may innovative way to conduct a P/11 The scanner comes with a rugged,
vary dependant on the type of defect. inspection. weatherproof field pack, which can be
The P/11 procedure was originated in This method uses laser sensing used in all environments including
August 1974 as BGC/PS/CP/P11 and technology to obtain the data excavations, work at height and
has been edited and revised 12 times necessary to create a 3D image of the confined spaces.
to date. The procedure available today pipeline in the Pipecheck software. To conduct the assessment, the
is very different to the original, A laser is projected onto the pipeline technician first places 6mm magnets
however the method of inspection has and a set of two cameras record the approximately 100mm apart on the
hardly changed. laser line curvatures, following the pipeline (see Figure 1). This is to
The traditional method of surface shape in real time. enable the Pipecheck software to
conducting the procedure was to take The scanner has the ability to cover recalibrate the scanner.
various mechanical measurements 100 per cent of the pipeline surface, The technician scans over the full
using straight edges and depth providing a huge amount of data circumference of the pipeline,
gauges to obtain the necessary points. Having a complete set of data approximately 250mm off the pipeline
measurement data and assess the increases the operator’s confidence in surface along the defected area, until
defect. When inspecting areas of the results. the image has been created and the
corrosion on a section of pipeline, a The time taken to scan a section of data validated in Pipecheck software
large amount of data is required to pipeline is constant, regardless of the (see Figure 2).
properly assess the corrosion, so this defects present, and the scanner can Creaform conducted a case study
is a very lengthy process and can produce results up to 80 per cent whereby a section of defected pipeline
result in limited data quality. faster than the traditional method. containing a dent was assessed by
Inspecting a large section of The traditional method falls down four independent mechanical damage
corrosion or an area with multiple when inspecting defects in close technicians using the traditional
defects present can become very proximity to welds (both seam and method. The same four technicians
costly due to the inspection taking a girth welds), on bends, near tees and then assessed the same defect using
number of days. near pressure points/stabbings. the scanner.

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