Pipe girth weld automated ultrasonic testing system qualification and project specific procedure validation
|Publication Date:||1 September 2019|
The Scope of this document is to provide a uniform guideline for the general qualification of automated ultrasonic testing (AUT) systems according to the requirements for qualification of such systems given in DNV GL standard DNVGL-ST-F101 App.ESubmarine pipeline systems. This qualification activity will document the specific AUT system performance in terms of inherent functionality related to non changeable hardware, software and calibration philosophy. Qualification activity following this guideline will also document the AUT system performance in terms of POD and sizing capabilities relevant for applications where the essential variables remain within the specified tolerance as given in DNVGL-ST-F101 App.E and [2.4] in this document. The intention with this general qualification is to provide a repeatable and auditable process for AUT system qualifications allowing project specific validations where the scope for the project specific validation can be designed to verify compliance with the general AUT system performance as documented in the general qualification. The extent of this validation will depend on the identified deviations from essential variables referenced in DNVGL-ST-F101 App.E and [2.4] in this document as well as any pre requisites referenced in the general qualification document. A recommended scope for a project specific validation is included in this RP.
This document describes in details the specific system requirements, input requirement, qualification process and data analyses process. The scope includes qualification of any AUT system to document reliability, repeatability and accuracy for detection and sizing of defects in pipeline girth welds. In principle, the recommended practice (RP) can be utilised for all materials but special care shall be taken for applications where inconsistent wave propagation or other wave physics are affected by structural properties such as anisotropic materials. In such applications, a specific assessment shall be made to determine the adequacy of the implementation of this RP.