San Diego, CA – Diakont, a worldwide provider of pipeline inspection services, has developed an innovative technology for examining girth welds from within the pipe. Diakont’s robotic in-line inspection (ILI) girth weld scanner performs high-resolution ultrasonic scans using the dry, non-contact electromagnetic acoustic transducer (EMAT) method.
Diakont's reliable girth weld scanning solution validates whether any cracks, voids, or crack-like defects are present in the girth welds, which could become critical in the presence of certain external forces. By using an in-line method, the girth weld scanning tool performs inspections without requiring expensive large-scale excavations or removing external pipeline coatings, making it an ideal solution for long lengths of pipelines, encased lines, or lines beneath road or river crossings.
Girth welds are challenging to inspect due to their coarse, anisotropic grain structure which attenuates the signal and creates wave velocity variances. A large dataset, comprising various angles and frequencies, is required in order to capture all resulting reflections. Diakont solved this issue with a multi-channel frequency-time (FT) EMAT scanning technique. This technique generates a set of nine FT scans on each side of the girth weld, with each frequency corresponding to a different input wave angle. In real-time throughout the weld scan, the nine FT scans are sequentially overlaid and fused into a single combined dataset using an algorithm that calculate values throughout the scan area. This proven inspection technique provides high-resolution integrity data on the entire volume of girth welds.
"Anyone can inspect pipeline girth welds during installation – that's easy, but to inspect girth welds of buried lines takes a highly advanced solution," said Katherine Foster, ILI Solutions Executive of Diakont's Advanced Technologies Division. "The in-line girth weld scanning technique is the latest innovation from Diakont that gives operators a reliable and practical solution for ensuring that each component of a pipeline meets integrity needs."
In 2013, Diakont successfully completed multiple pilot inspection projects using the in-line girth weld scanning technology. These projects were performed on gas and liquid pipelines for operators in North America and Europe. Based on the successful inspections and corresponding favorable validation results, Diakont has already been contracted to perform girth weld inspections during 2014 on large diameter piping at six natural gas compressor stations.
Diakont is a full-cycle engineering, manufacturing, and service company that provides high-tech solutions which enhance the safety and economy of the pipeline and energy industries. With a North American operation in San Diego, California, Diakont is a leading manufacturer of advanced robotics and inspection equipment that ensure the safe operation of pipelines and facilities. Diakont’s comprehensive inspection services have facilitated pipeline integrity management programs for operators worldwide.