NDTnet 1998 Aug, Vol.3 No.8

Abstract

The ultimate goal in the development of in-line inspection tools is to permit cost effective decisions regarding repair, replacement, preventative maintenance or even new procedures for new pipeline construction. This necessitates accurate and reliable in-line surveys in order to assess all relevant anomalies with confidence.

Magnetic Flux Leakage (MFL) technology is one of the most cost effective inspection methods currently used. A new line of MFL tools were developed to meet the new and high demands particular from the offshore pipeline operators.

The improvement includes the technology, the on-board systems and the signal processing after the data is retrieved from the tool.

The on-board system has to consider that the tool is a free swimming, self-contained unit and therefore must address the following issues:




• Sealing cups to provide driving thrust from the product flow
  
• Magnetizing unit powerful enough to saturate the pipe wall
  
• Compact, wear resistant, flux leakage sensing elements
  
• Data acquisition system for signal processing
  
• Data storage with multi-giga-byte capacity
  
• Power sufficient to supply all on-board systems
  
• Pressure vessels to house electronic
  
• Shock & vibration damping systems for critical components
  
• Location & odometer systems for tracking tool position

  The off-line data processing and the data analysis methods are the final part of any inspection system. The data processing has to extract the required features for the data analysis as well as ensuring the data integrity.

  The base technology was the starting point, together with the large know-how already available, for the data analysis.

  Due to tool verification, the performance was found to exceed the expectation first set up for the tool in terms of detection ability.

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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