Subsea 7 invites proposals from organisations and experts to provide a fully automated Non-Destructive Testing (NDT) analysis of pipeline welds. The proposed solution will determine the quality of the welds and provide automated feedback and decision making of the results against agreed acceptance values. Ideally, the inspection system would be fully automated or potentially compatible with robotic systems to minimise the operator interaction on the pipeline fabrication.
A two phased approach would be expected with both visual inspection of the weld surface and volumetric analysis of the underlying weld structure being vital to the quality control process.
The inspection system should have closed loop control with the welding system to enable real time optimisation of welding parameters based on inspection results in order to minimise the incidence of unacceptable flaws.
Visual inspection of completed girth welds is currently performed by a qualified inspector
Volumetric inspection of pipeline welds during fabrication currently utilises Automatic Phased Array Ultrasonic Testing (PAUT). An array of probes are attached to the outside of the pipe manually and move around the pipe circumference on a motorised scanning frame.
Two operators are required to supervise the rotating scanning frame and an additional skilled technician monitors and interprets the signals. Individual ultrasonic responses associated with weld flaws are accepted or rejected against pre-determined acceptance criterion.
The following characteristics should be considered in the final technology offering:
Suitable for fully automatic deployment
Suitable for in-situ pipeline fabrication inspection
Should not exceed critical production cycle times (3-20mins depending on pipe size and grade)
Required inspection equipment should be compact and non-intrusive as far as is practical
Required inspection procedure should not require special preparation of the pipe surfaces to be inspected
Typical girth weld surface for visual inspection
Typical weld through thickness section for volumetric inspection
Key success Criteria
Suitable for carbon steel, clad and Corrosion Resistant Alloy (CRA) metallic materials in wall thicknesses 6-45mm and diameters 150- 500mm.
Detect and size potential flaws >0.5mm in height.
Detect and size potential flaws >3mm in length.
Can detect both planar and volumetric flaws
Optical (Lasers / Cameras etc)
Other non-destructive testing methods
Approaches not of Interest
Any systems that require offline inspection and analysis.