Page 82 - Pipeline Pigging Technology

Pre-tnspection-survey activities

With regard to the design of cleaning pigs, the following features are of
importance:

Brushes/blades materials
configuration
suspension

Cups shape
mounting (influences stiffness)
thickness
hardness
(over) size
number of cups per pig

Discs hardness
thickness
(over) size
mounting (influences stiffness)
number of discs per pig

This information, together with the available pipeline data, forms the basis
for determining the pre-inspection cleaning programme.

OPTIMIZATION OF INSPECTION RESULTS

Cost-effective suggestions for optimizing inspection results include:

(a) analyze available information in-house, using the above-mentioned
suggestions, at no external cost;
(b) provide a written analysis to the pipeline inspection contractors
tendering for the inspection contracts. It is essential to provide information
for each pipeline;
(c) decide whether it is feasible to carry out the cleaning activities using in-
house personnel and equipment, or by asking the contractor to include it in
the scope of work. It is also suggested that consultancy services should be
considered for the supervision of the in-house cleaning activities in a cost-
effective manner;

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