Speir Hunter Ltd, in partnership with the University of Leeds in the UK, has engineered the science of stress-magnetisation to create a remote pipeline inspection tool which is used by integrity engineers worldwide on both piggable and non-piggable lines. This groundbreaking technology is called Stress Concentration Tomography, commonly referred to as SCT™. SCT™ is the only inspection technique in the world that can simultaneously map the lateral position and depth of cover of the pipeline whilst also providing comprehensive defect detection. Moreover, it provides additional deliverables that anticipate the increasing demand of pipeline regulatory authorities such as the location of casings and wrinkle bends. SCT™ exploits the measurable relationship between stress and magnetization: changes in localised stress on the pipeline wall cause predictable changes in the pipeline’s natural magnetic field. The analysis of this remotely collected magnetic data is then used to determine the presence of defects, their location and their magnitude of stress.
UNISCAN
is the hardware used to collect raw data for analysis. It is composed of:
- An array of sensitive magnetometers that collect data on the pipeline’s natural magnetic field from a distance.
- A high-precision GNSS positioning system to stamp locational data onto magnetic data in real-time.
- Complex firmware to control electronic functionalities and to record magnetic locational data onto a USB stick for analysis in UNISCAN™ Tools.
COMPREHENSIVE DEFECT DETECTION
SCT™ directly measures the quantity of stress on a pipeline wall by analysing remotely collected magnetic data. This means that SCT™ can detect any type of defect occurring in a pipeline in any orientation, internal or external, and irrespective of the clock position of the defect. If it causes a localised increase in stress on the pipe wall then SCT™ will detect and report it to sub-meter accuracy.
