EN 583-6:2008

Foreword
1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviations
   3.1 Terms and definitions
   3.2 Abbreviations
   3.3 Symbols
4 General
   4.1 Principle of the technique
   4.2 Requirements for surface condition and couplant
   4.3 Materials and process type
5 Qualification of personnel
6 Equipment requirements
   6.1 Ultrasonic equipment and display
   6.2 Ultrasonic probes
   6.3 Scanning mechanisms
7 Equipment set-up procedures
   7.1 General
   7.2 Probe choice and probe separation
        7.2.1 Probe selection
        7.2.2 Probe separation
   7.3 Time window setting
   7.4 Sensitivity setting
   7.5 Scan resolution setting
   7.6 Setting of scanning speed
   7.7 Checking system performance
8 Interpretation and analysis of data
   8.1 Basic analysis of discontinuities
        8.1.1 General
        8.1.2 Characterisation of discontinuities
        8.1.3 Estimation of discontinuity position
        8.1.4 Estimation of discontinuity length
        8.1.5 Estimation of discontinuity depth and height
   8.2 Detailed analysis of discontinuities
        8.2.1 General
        8.2.2 Additional scans
        8.2.3 Additional algorithms
9 Detection and sizing in complex geometries
10 Limitations of the technique
   10.1 General
   10.2 Accuracy and resolution
        10.2.1 General
        10.2.2 Errors in the lateral position
        10.2.3 Timing errors
        10.2.4 Errors in sound velocity
        10.2.5 Errors in probe centre separation
        10.2.6 Spatial resolution
   10.3 Dead zones
11 TOFD examination without data recording
12 Test procedure
13 Test report
Annex A (normative) - Reference blocks
Bibliography

This European Standard defines the general principles for the application of the Time-Of-Flight Diffraction (TOFD) technique for both detection and sizing of discontinuities in low alloyed carbon steel components. It could also be used for other types of materials, provided the application of the TOFD technique is performed with necessary consideration of geometry, acoustical properties of the materials and the sensitivity of the examination.Although it is applicable, in general terms, to discontinuities in materials and applications covered by EN 583 1, it contains references to the application on welds. This approach has been chosen for reasons of clarity as to the ultrasonic probe positions and directions of scanning.Unless otherwise specified in the referencing documents, the minimum requirements of this standard are applicable.Unless explicitly stated otherwise, this standard is applicable to the following product classes as defined in EN 583 2:class 1, without restrictions;classes 2 and 3, restrictions will apply as stated in Clause 9.The inspection of products of classes 4 and 5 will require special procedures. These are addressed in Clause 9 as well.The techniques to use TOFD for weld inspection are described in CEN/TS 14751. The related acceptance criteria are given in prEN 15617.