Dacon Invests in LRUT Pipeline Inspection System


Dacon Inspection Services recently invested in Long Range Ultrasonic Testing (LRUT) equipment and training to support client requirements. LRUT is an advanced technology for detecting and analyzing corrosion where access is difficult and allows scanning of large areas of pipeline surface from a single inspection point. Large areas of coverage from a single “shot” mean it is faster and more efficient than conventional Ultrasonic Thickness Measurement methods. LRUT can be applied to many different pipe types, pipe coatings, pipe materials and pipeline situations.

Using the new equipment and in house expertise Dacon recently completed pipeline system inspections at Tank terminals in Thailand and several Tank terminals in the Philippines. The scope of the projects also involved operating the LRUT system while working at height and required IRATA certified rope access technicians to work in combination with the LRUT inspection teams. It is this unique capability to combine specialized expertise with advanced inspection techniques that makes dacon stand out from its competitors.

LRUT Benefits

• Low cost screening with 100% coverage
• Focusing capability to evaluate corrosion distribution around pipe circumference
• Typical test range 60m from single location, ideal conditions can achieve 350m
• Testing of pipes up to 48” diameter
• Proven capability on pipe in service up to 125C
• Ideal where conventional testing is impossible or very costly e.g. clamped, insulated, elevated, sleeved or buried pipes


• Low frequency ultrasound is transmitted and received from a single location
• The guided waves used travel long distances, even in buried, submerged or insulated pipe
• Response from flaws is a function of their depth and circumferential extent
• Focusing allows ultrasound energy to be concentrated into a small region of pipe for detailed localized inspection.
• Uses ‘multi-mode’ technology to characterize and quantify any flaws detected


Pipe types
• Seamless
• Longitudinally and spiral welded

Pipe materials
• Ferritic and stainless steels
• Other metals

Pipe situations
• Buried
• Air-to-soil interface
• Air-to-water interface
• Elevated on racks
• Sleeved in road crossings
• Wall, bund or berm penetrations

Flaws found
• External corrosion
• Corrosion under insulation (CUI)
• Internal corrosion or erosion

Pipe coatings etc.
• Foam or mineral wool
• PVC, epoxy, coal tar epoxy
• Paint
• Bitumastic wrapping

Pipe duties
• Transmission and distribution lines
• Refinery and chemical plant
• Offshore risers
• Jetty lines
• Tank farm link lines
• Power plant service pipe
• Storage sphere support legs
• Headers