Michael Beller (presenter), Carlos Enrique Sabido , Daniel Schaller Tom Steinvoorte , Stefan Vages, Klaus-Peter Zimmermanns
More than 50% of the global oil or gas pipelines have until recently been considered “un-piggable”. This term is used when a pipeline cannot be inspected with a free-swimming in-line inspection tool for instance because of missing launching and receiving facilities, diameter variations...
More than 50% of the global oil or gas pipelines have until recently been considered “un-piggable”. This term is used when a pipeline cannot be inspected with a free-swimming in-line inspection tool for instance because of missing launching and receiving facilities, diameter variations, tight bends, low pressure and flow conditions or high pressure and high temperature environments, onshore or offshore.
In this paper a new concept is introduced, the so-called “toolbox approach”. The driving idea behind the concept is based on having a large variety of services with all the required technologies, including magnetic flux leakage (MFL), eddy current or ultrasound, enabling tailor made solutions to be packaged utilizing exactly the right technical resources for a specific inspection and integrity challenge.
But it is not limited to a technology perspective. It also uses market information to identify mid- and long term market needs as well as special operational procedures. The resulting combination of understanding market needs, requisite know-how regarding optimized methods for service execution and the right set of inspection technologies and transportation means results in utmost flexibility and optimal solutions for operators faced with managing the integrity of their challenging pipelines.
In addition it must be stated that this type of work relies heavily on the expertise and experience of the crew involved, because of the often extremely complex boundary conditions and operational parameters encountered during the job performance.
This paper will introduce the concept and use three case studies to illustrate specific tailored solutions.
First the case study of a highly complex inspection of flow lines, where access to the 10” oil-multiphase lines was only possible by using 3-way ball valves originally designed for cleaning scrapers. Here a specially designed 10” bi-directional free swimming magnetic flux leakage tool was used, short enough to be launched through the ball valve, but still incorporating full high resolution capabilities. The advantage of using MFL was that the job could be performed during operation of the pipelines.
The case study will also introduce additional and complimentary services from the toolbox, in this case an automated and remotely operated benchmark identification system as well as a high resolution approach monitoring system which was used to precisely detect tool movement and final approach to the receiving ball valve.
Secondly an inspection will be described where a highly specialized robotic system, the so-called Helix system was used to inspect challenging horizontal gas storage tanks with complex operating conditions and limited access. The inspection itself was also performed with MFL technology.
The third case study describes the inspection of upstream laterals without regular launching and receiving facilities, where another specialized robotic tool, the Multi-Trotter-Crawler was used to pull a MFL unit to inspect for metal loss and corrosion.
All three case studies describe the technology used, the procedures applied as well as an overview of the results obtained.