NDT - Non Destructive Testing
OSCAR (Optical Scanning Apparatus for Rope) is TTI’s non destructive rope testing method. Developed under a Smart Award and as an EU funded Craft Project, Oscar is a patented System based on an Optical Fibre Method using Brillouin Scattering, Bragg Gratings or Microwave.
Special Transducer built into or attached to the rope
The system, invented by TTI and the University of Strathclyde, detects changes in rope elongation in real time along the rope length. This information is used to detect local damage in a rope, which can be caused by an accident; for example during rope installation. It can also be the result of long term rope fatigue.
A Special Transducer built into or attached to the rope allows the system to be used in high elongation polyester ropes
The transducer consists of lose tube optical fibres cabled at a high helix angle. This gives a gearing between the optical fibre and the transducer elongation as shown in the figure below.
System tests at the National Engineering Laboratory have demonstrated Oscar’s capability to detect damage. Cuts in a polyester parallel strand ropes showed clearly identifiable peaks in the optical fibre response as shown in the figure below.
Scan of the strain profile in the fibres with a 7.5 ton load applied
A complete system is available from the OSCAR Consortium
TTI’s OSCAR Consortium partners:
BPP – System Integration
Bexco Ropes – Manufacturer of Large Fibre Parallel Strand & Wire Rope Constructions
University of Strathclyde – Advanced Optical Fibre Measurement Technology
Leuveco – Manufacturer of Special Marine Terminations
E-mail : firstname.lastname@example.org
Selantic - Manufacturer of high performance slings