THE Applus+ SOLUTION
Applus+ RTD provides pipeline inspection through qualified, highly skilled operators and its own field-proven, mechanized, ultrasonic-inspection system: Rotoscan. As with all Applus+ scanners, Rotoscan is designed to be handled by a single operator (with a standard scanner, a second operator is needed to handle the guiding band). An electric drive motor provides the scanning motion. An encoder measures positions around the circumference.
Pipeline girth welds are divided into a number of depth zones related to the wall thickness and weld bevel configuration. Full inspection coverage is achieved by placing ultrasonic probes (either conventional or phased array) on both sides of the weld such that each generated inspection function or probe examines a dedicated depth zone within the weld. This eliminates the need to move the probes to and from the weld, as is conventional practice in time-consuming manual ultrasonic inspections. The inspection time using Rotoscan is approximately 5 minutes, depending on pipe circumference and chosen scanning speed.
Applus+ RTD custom designs and manufactures ultrasonic probes to the specific weld configuration and material (angle, frequency and focus) of each individual pipeline project. Probes can also be designed to withstand high-temperature pipe surfaces, in particular for offshore barge construction.
Rotoscan can be configured with the use of conventional or phased array ultrasonic probes and can be equipped with two different types of scanners in combination, with 3 frame options to cover a wide range of pipe diameters from 5cm to 142cm (2” to 56”).
Moreover, the integrated and simultaneous TOFD feature provides additional information to assist in the evaluation of indications.
The Rotoscan system incorporates computerised data presentation and storage. The on-board computer enables ultrasonic signals to be digitised, which is essential for coherent C-scan mapping and the use of Time of Flight Diffraction (TOFD) within the system. In addition, the software allows for the automatic judgement of indications and generation of defect lists.
Applus+ RTD works according to all customary standards, including ASTM 1961, API 1104 and DNV OS F101. Additionally Applus+ RTD has qualified its system with DNV for pipeline projects with a wall thickness of between 6mm and 30mm. The wall thickness range on which the system can be applied varies from 6 to 45mm.