ULTRASONIC CRACK-DETECTION IN DEMANDING PIPELINE ENVIRONMENTS AND LOW DIAMETER PIPES

Ultrasonic crack detection represents a reliable and accepted in-line inspection technology for the application in liquid media. The technology is long standing and considered as industry standard [1-3]. As a result of various demands, e.g. increased temperature levels above 70 degrees C, high pressures exceeding 100 bars and medium types (e.g. heavy crude oil) with inherently high damping and temperature dependency of the damping characteristic the complexity can be primarily found within the bounding conditions. The reduction of inner pipeline diameter, e.g. below 120 mm, represents a further increase of degree of complexity. This paper gives access to the design and development approach chosen by ROSEN for ultrasonic crack detection tools and the case of pipelines with an outer diameter ranging from 6 '' to 8 ''. All previously mentioned issues and requirements are considered. The mechanical design of the ultrasonic crack detection tools is described.