Reading Through 3LPE & 3LPP Coatings

3LPE (Three-Layer Polyethylene) or 3LPP (3-Layer Polypropylene) coatings is used to protect the external wall of pipes and consist of three distinctive layers: fusion bonded epoxy; copolymer adhesive layer and; a polypropylene or polyethylene layer.

Three-Layer PE or PP coated pipes are the industry standard coatings for the transmission of oil & gas via buried pipelines due to its ability to withstanding a wide variety of temperatures and environments. Although there are huge benefits to 3LPP / 3LPE coatings, they can also make it harder to carry out simple thickness measurements of the internal wall, where corrosion is occurring on the inside of a pipeline out of sight.

All Cygnus ultrasonic thickness testing equipment employ the Multiple-Echo technique which is perfect for measuring metal thickness through paint up to 20mm thick, providing accurate and reliable ultrasonic thickness measurements. The Multiple-Echo measuring mode enables thickness measurements to be taken without need to remove or damage any aspect of the 3LPE / 3LPP coating, returning only the internal steel thickness measurement.

  • Cygnus 1 Intrinsically Safe: Certified to Class 1, Div 1 (“Zone 0”) for ATEX, IECEx and CSA-US, making it ideal for potentially explosive atmospheres.
  • Cygnus 4+ General Purpose: Features a large LCD display, linear data logging for recording measurements and A-scan display to help verify measurements.
  • Cygnus 6+ PRO: Offering A-scan and B-scan, manual gain control and comprehensive datalogging with auto-log function.