Page 367 - Pipeline Pigging Technology
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Pipeline Pigging Technology
Deviations from the model (adjustment residuals) give the cross-sectional
picture of the pipe with determination of dents and ovality, as shown in Fig.2.
The on-board processing consists mainly of packing the data to take as little
tape space as possible. On recovery, the processing consists of:
spinning the data to the correct clock position, based on the accelerom-
eter output from the inertial system;
correcting for offset of the sensor from the centre of the pipe;
correcting for changes of the velocity of sound in various media.
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