The Latest European Standard on TOFD Technique

The new requirements of the latest European standard CEN/TS 14751:2004 Use of Time-of-Flight Diffraction Technique(TOFD)for Examination of Welds were introduced.There are a lot of new provisions such as four examination levels(A,B,C and D),recommended TOFD set-ups for butt-welds dependent on wall-thickness,time window and sensitivity settings,the details of notch type and side-drilled type of reference blocks,the essentials of divisional scan,centric scan and eccentric scan etc.Also,18 examples of typical TOFD-images of displaying quality and weld discontinuities,especially some new measures overcoming the inherent disadvantages of TOFD technique were given.The intention was to provide a new reference for spreading and applying the new technology in China.