Welding codes and standards usually require the qualification of welding procedures prior to being used in production. This is to ensure that welds will meet the minimum quality and mechanical property requirements for the application. This article provides an overview of the welding procedure qualification guidelines and test methods. It also reviews the codes, standards, and specifications that govern the design and fabrication of welded structures for the procedure qualification details that are appropriate for a given application.

Weld shrinkage data models were developed for thin uniform and complex ship panels to predict in-plane shrinkage. The complex features in the thin panels include cutouts, inserts, multiple thicknesses, and nonrectangular-shaped panels. By analyzing the measured data, it was found that there was no clear indication that a cutout affected the overall panel in-plane shrinkage, although it induced more out-of-plane distortion. It was observed that the inserts induced additional butt joint across-weld and along-weld shrinkage and did not affect the fillet-weld shrinkage. The weld shrinkage data models were embedded in Microsoft Excel spreadsheets for ease of use. The spreadsheets permit the user to input the panel design parameters including material type, plate thickness, stiffener shape, spacing, and length, and overall panel dimensions as well as complex-panel features that include inserts, multiple plate thicknesses, and nonrectangular-shaped panels. The user can also provides fabrication details such as the welding process, weld sizes, welding parameters, and the use of fixtures.

No abstract

Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.

Two distortion modeling methods, mapping plastic strain and lump-pass modeling, were developed and validated for predicting distortion on large welded structures to reduce the computation time. The mapping plastic strain method requires two kinds of models, local models and a global model. The local models are analyzed to predict plastic strains, and the global model is analyzed by mapping the plastic strains to predict distortions. The lump-pass modeling method includes two kinds of analyses: a thermal analysis and a thermomechanical analysis. The thermal analysis is conducted to predict temperature history. The thermomechanical analysis is performed to predict distortion by inputting the predicted temperature history.