Main Issues of the European TOFDPROOF Project

摘要

The European TOFDPROOF project (contract n° G6RD-01-00626., 2002 - 2005) aimed at producing a coherent package of E.U. agreed documents (procedures for applying TOFD with related acceptance criteria and recommendations for training and certification) based on a Round Robbin Test performed on welded specimens and validated through site trials. The project was focused on all aspects allowing the effective application of the TOFD as a stand-alone method for the weld inspection during manufacture of pressure equipment. Technological, regulatory, human factors were considered. The performance of TOFD was compared with conventional NDT as defined by European standards for testing pressure vessels at the manufacturing stage. This evaluation was carried out by means of a Round Robbin Test on welded specimens. All the results generated by this round robin exercise was stored in a data base set up on a Web site. Results produced were in a suitable form for implementation in CEN standards and dissemination among NDT specialists. Specific tools analysis was developed in order to enable a quick and reliable comparison of the TOFD results with those obtained by conventional NDT. Optimised TOFD procedures and specific related acceptance criteria were developed and applied. The influence of the objectiveness of TOFD inspectors were assessed after to have been trained with an interactive training guideline developed through the project and based on TOFD images collected from the Round Robbin Test. Recommendations for training and certification of personal were written and distributed to the NDT society, the relevant standardisation CEN technical committees and the EU companies dealing with weld inspection. TOFD with the corresponding acceptance criteria were then applied on site on welded components in order to demonstrate the technical efficiency and cost competitiveness compared with conventional NDT. The economical analysis confirms that TOFD can be less expensive than conventional NDT techniques to inspect welds.