Diakont and Structural Integrity Associates, Inc. Complete First Buried Piping In-Line Inspection at a US Nuclear Power Plant


  • Inspect an 18” high-pressure coolant injection (HPCI) buried line at the Cooper Nuclear Station.


  • Use Diakont’s patented Electro-Magnetic Acoustic Transducer (EMAT) technology and customized robot to perform an inspection of the safety-related HPCI pipe section.


  • A 100% inspection coverage throughout the two 45-degree elbow fittings was completed.
  • There were no critical defects detected, and the piping system was returned to service following the inspection.

Diakont, along with strategic partner Structural Integrity Associates, Inc., recently completed the group’s first buried piping in-line inspection project at a US nuclear plant. The inspection was performed in October 2012 on an 18” High Pressure Coolant Injection (HPCI) line at Cooper Nuclear Station. Utilizing a crawler tool equipped with Diakont’s patented Electro-Magnetic Acoustic Transducer (EMAT) technology, the team performed a 100%-coverage inspection of the safety-related HPCI pipe section. Inspection preparations by Structural Integrity included code-based, finite element analyses to establish the acceptance criteria in the event that metal loss was discovered, thereby minimizing any potential outage schedule impact. There were no critical defects detected, and the piping system was returned to service following the inspection.

The RODIS-18 inspection tool was developed specifically for this project, leveraging robotic and inspection elements from Diakont’s RODIS-28 tool. Modifications were made to accommodate the piping system diameter, and to provide 100% inspection coverage throughout the two 45-degree elbow fittings. Many of the robust design features of the existing technology were maintained, including the EMAT module, ensuring familiarity for the robot operators and NDE technicians. As part of the development and qualification process, a full-fidelity mockup was fabricated at Diakont’s facility to test robot navigation and EMAT operations, as well as to provide the required crew training. Structural Integrity was integral to the development and field implementation process, providing finite element analysis, commercial-grade dedication support, and data management using the BPWorks™ database.

Edward Petit de Mange, Managing Director of Diakont added, “Diakont, working with Structural Integrity, proved to be a highly-proficient team for the HPCI buried piping inspection at Cooper Nuclear Station. Utilizing Diakont’s versatile crawler coupled with Structural Integrity’s project oversight and analysis, the team provided accurate, comprehensive inspection results within the tight outage-driven timeframe.”

Steve Biagiotti, PE, Sr. Associate and Nuclear Buried Pipe Product Manager for Structural Integrity shared his agreement. “The ability to perform UT remaining wall thickness examinations from the inside of a pipe using a single access point and without the need to excavate buried piping provides the nuclear power industry with a new tool in their arsenal to further assure stakeholders of the continued integrity of these systems. We are pleased to be working with Diakont on this endeavor to provide industry leading technology solutions.”

About Diakont

Diakont is a full-cycle engineering, manufacturing, and service company that provides high-tech solutions which enhance the safety and economy of the nuclear power and pipeline industries. With a North American facility located in San Diego, California, Diakont is a leading manufacturer of pipeline inspection robotics, digital I&C systems, fuel handling equipment, and radiation-tolerant camera systems. Diakont products are utilized worldwide on power plants of all designs.

About Structural Integrity Associates, Inc.

Structural Integrity Associates, Inc. is an internationally recognized engineering leader in prevention and control of structural and mechanical failures. Headquartered in San Jose, California, Structural Integrity serves clients worldwide with a dozen branch offices throughout the United States and Canada, as well as affiliates in China, Japan, Korea, and Spain. Structural Integrity’s expertise in buried piping programs and data management has helped nuclear power plants worldwide.