Advantages of GUL

  • Screens pipe for metal loss such as corrosion and erosion
  • Can identify C.U.I. damage without removing insulation
  • Capable of showing wall loss 9% and greater
  • Capable of showing the orientation of the wall loss circumferentially and longitudinally in terms of the distance from the transducer or agreed upon datum
  • Can be configured to inspect 1.5” diameter up to 48” diameter pipe
  • Originally developed for use in petrochemical plants but has expanded to pipelines (Road Crossings) and bridge piers.
  • Only needs 2.5” of clearance between piping
  • Real time data analysis
  • Can be used to test piping at temperatures up to 257°F unless high temperature rings are used this can expand the temperatures up to 644°F
  • Can be used to test piping that is submerged in water
  • Typical inspection ranges of 100’ in each direction can be expected under ideal conditions 590’ can be achieved
  • Portable battery powered equipment
  • Rigorous operator training and certification with individual electronic keys to track operator use

Disadvantages G.U.L.

  • Needs 1.5’ of bare pipe in order to mount the transducer ring
  • Ideally mounted 3’ from nearest girth welds
  • Does not perform well when testing around elbows
  • As the viscosity of the pipe contents increases the range of inspection decreases
  • Piping with general heavy corrosion will be detrimental to the range of the inspection
  • Heavy corrosion at the location the transducer ring is placed can be detrimental to a successful
  • inspection requiring the area where the ring is to be placed to be scanned using straight beam ultrasonic examination
  • Bonded polyurethane insulation leads to loss of ultrasound reducing the inspection range.
  • Concrete coated piping can prevent or limit inspection ranges
  • Other tightly adhered coatings can also prevent or limit inspection ranges
  • Inspection range is affected by welds, typically a weld will reflect 20% of the signal, 6 weld sets the maximum span
  • Complementary inspection methods are need to map out and size flaws found with G.U.L.