Abstract
ABSTRACTThe Welding Institute of Canada (WIC) test is a simple and standardised weldability test for hydrogen assisted cold cracking that was developed in the 80s. It has been extensively utilised by the industry to qualify safe welding envelopes but the difficult access to the weldment by instrumentation hinders its use for scientific research. Moreover the lack of repeatability arising from the traditional manual deposit and the short weld length causes industrial trials to have a low success rate. The present work proposes a modified geometry, referred to as the modified WIC (MWIC) test that shows: (1) an improved success rate of weld deposition, (2) an enhancement to instrument the weldment and (3) welding conditions in better accordance with the field pipeline girth welding conditions. The design is validated under a mechanised, shielded metal arc welding process with the cellulosic electrodes used for in-field pipeline construction.
Highlights
The pipeline industry has long desired the establishment of standardised weldability tests in order to quantify the susceptibility to hydrogen assisted cold cracking (HACC) of pipeline girth welds [1,2,3], a significant threat to pipeline weld integrity
A new modified WIC (MWIC) weldability test and test procedure have been developed that allows for the experimental determination of the critical strain needed for cold cracking formation post-welding
The modifications allowed obtaining a significant increase in success rate of achieving an industry acceptable weld in the tests
Summary
The pipeline industry has long desired the establishment of standardised weldability tests in order to quantify the susceptibility to hydrogen assisted cold cracking (HACC) of pipeline girth welds [1,2,3], a significant threat to pipeline weld integrity. The predominant advantage of such standardisation is the ability to compare weldability test data across a range of sources reliably and with confidence. This is becoming ever more important as the prevalence of weld metal HACC (WMHACC) is increasing [4,5,6,7] and major standards such as the Australian Standards AS2885.2:2007 [8] and the European Standard EN 1011-2:2001 [9] do not provide guidelines on specific procedures such as preheating to minimise the risk of cracking. HACC is complex in nature, involving interplay between hydrogen and thermal, mechanical and metallurgical factors. Since the underlying mechanism governing this phenomenon is not well understood, it is still a contentious subject today
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
