Innerspec’s Long Range UT (LRUT) options include a simplified version with just an circumferential ribbon for axis-symmetric transmission and reception, and a more sophisticated version that provides synthetic focusing using a scanner for reception. These wave modes are optimised for Long Range Pipe Inspection.
Unlike conventional rings, Innerspec’s LRUT tool does not create flexural modes during transmission due to the uniform loading around the circumference generated by the Ribbon.
During reception on the other hand, defects will naturally generate flexural modes since they are not distributed uniformly around the circumference. Innerspec’s LRUT Scanner is able to make discrete stops as per the maximum number of Torsional Flexural modes which can exist based on the pipe geometry and frequency. The complete data from “n” stops is used to resolve maximum possible flexural modes providing much better focusing and resolution.
As an example, a high-density traditional ring with 16 channels will be able to provide maximum resolution of 22.5º (45º for a conventional 8 channel ring), whereas on an 8” pipe, Innerspec’s LRUT Scanner will make 40 stops that equate to 9º of circumferential resolution. In addition to better focusing, the Axis-symmetric wave mode will also provide smaller dead zone and greater penetration. During experiments typical defects of 1.5% CSA and smaller can be detected in ideal conditions.