1. Scope

The scope of the EN 1714 is intended for the ultrasonic examination of full-fusion welds in ferritic materials with a minimum plate thickness of 8 mm. The standard can be applied by agreement between contract partners on other materials, weld configurations and automatic testing. The scope defines four examination levels which are directly related to the European welding standard EN 25817 'Guidance on quality levels for weld imperfections'.

2. Normative references

3. Definition and Symbols

For two symbols the standard use variations between the three standard languages German, English and French. The German version uses D_KSR (Durchmesser eines Kreisscheibenreflektors) and D_QB (Durchmesser einer Querbohrung) while the English and French version use D_DSR (Diameter of the equivalent disc-shaped reflector) and D_SDH (Diameter of a side drilled hole).

4. General

The standard defines the test equipment, preparation, examination procedure and the test report. The determination of characteristics, especially of the probes, refers to the draft standards and prEN 1713.

5. Necessary Information before testing

The sub-clauses 5.1. and 5.2 describe details which contracting partners may have to define.
Sub-clause 5.3. points out that written procedures are not required when working strictly within the parameters stated within the standard for a particular examination level. However, the standard makes it clear that written procedures must be used when specified by contract.

6. Personnel and Equipment Requirements

6.1 personnel qualifications must be in accordance with EN 473 or equivalent.
6.2 claims that the applied equipment must fulfill other European standards, or if those are still not ready the equivalent national standards shall be used.
6.3.1 permits probes of only 2 MHz to 5 MHz frequencies, however, exceptions are possible. If improved resolution for characterization is needed (e.g. in prEN 1713) a higher frequency can be used. A probe frequency of approx. 1 MHz can be used in cases of long sound paths.
6.3.2 Angle of incidences. This clause describes in particular the bounce angle on the coupling's far surface side (V-technique), which must lie within a range of 35° to 70°. Usage on curved work pieces is described.
6.3.3 Modifications of probe faces on curved work pieces. There is a stipulation that the gap between probe shoe and work piece surface may not be greater than 0.5 mm. (That seems to be a loose approximation since no more probe characteristics are specified in this sub-clause).

7. Test volume

The examination must cover the weld and on both sides at least 10 mm of the parent material or the width of the heat affected zone (HAZ) if this is the larger value (Fig 1).

8. Preparation of scanning surfaces

The coupling surface does not have to be as rigorously controlled as in BS 3923 (appendix B) [..]. It permits scanning on almost any surface provided it is free from inconsistencies that prevent satisfactory probe coupling. However, on surfaces where the sound beam is reflected, the surface smoothness limits are specified for machined (R_a =6,3µm) and shot-blasted surfaces (R_a =12,5µm).

9. Examination of the parent material

Parent material under the coupling surface does not require an examination if this region is proven to be defect-free (the evidence can be an early inspection during manufacturing).

10. Range and sensitivity setting

10.1 General
10.2 Sensitivity level
Four methods of sensitivity level settings are described.
Method 1: DAC curve of 3mm D_SDH (diameter side drilled hole).
Method 2: AVG curve of 1 to 3 mm D_DSR (diameter of the equivalent disc-shaped reflector).
Method 3: DAC curve of 1 mm notch.
Tandem testing: D_DSR = 6 mm for the complete wall thickness range.
10.3 Evaluation levels
10.4 Transfer corrections
Describes procedures with respect to differences of characterizations between reference body and work piece under test.

11. Examination levels

The scope defines four examination levels which are directly related to the European welding standard EN 25817 'Guidance on quality levels for weld imperfections' (table 5).

12. Methods of evaluation

12.1. General Ultrasonic testing must be performed in accordance to prEN 583-1
12.2. Probe manipulation The probe can be swiveled +-10°
12.3. Testing of defects lying perpendicular to the coupling surface Such defects are difficult to test with the standard angle probe method. Special test techniques shall be used to detect those defects especially for thick-walled welds. The application of those test techniques must be agreed upon by contracting partners.
12.4 Localization of defects The location of the evaluated defects must be defined by a lay down in a coordinate system (see Fig 2)
12.5 Evaluation of indications The standard requires the amplitude (peaked) of an indication to be recorded, with respect to the applicable evaluation level, and its length, as determined by the 6 dB drop technique. That can be altered by agreement between the contracting partners. Other defect characteristics need only be recorded if defined by prior agreement between the contracting partners.

13. Test report

This chapter describes the items of a table of contents of a comprehensive test report.

Appendix A: Scanning requirements

Scanning requirements are comprehensively laid out in seven tables. They cover Plate and Pipe Butt Welds, Structural Tee Welds, Set-On and Set-Through Nozzle Welds, Structural 'L' Welds and Cruciform Welds. For each weld type a table defines the parameters, material thickness, examination level (A-D), scan surface width, number of required probe angles and the number of probe positions to be applied. Parameters are defined for longitudinal and transversal defects.
Table 2 summarizes some parameters of a Butt Weld.

Table 1
Weld Type	Material thickness	Scans	Long. Angle	Compression	Trans. Angle
Examination Level C
Single Butt	15-40	Scans	4	1	8
		Angles	2	N/A	2
Douple Butt	15-40	Scans	4	1	8
		Angles	2	N/A	2
Examination Level B
Single Butt	15-40	Scans	4	0	4
		Angles	2	N/A	1
Douple Butt	15-40	Scans	4	0	4
		Angles	2	N/A	1
Examination Level A
Single Butt	15-40	Scans	2	0	4
		Angles	1	N/A	1
Douple Butt	15-40	Scans	2	0	4
		Angles	1	N/A	1

Final editor's note:

I read the article " A comparison of Ultrasonic Weld Testing Standards: BS EN 1714 and BS 3923 Part 1" [..] The article expressed satisfaction, more or less, with the replacement of the BS 3923 by the new EN 1714. The new standard is seen as simpler and demanding less operator skills than the BS 3923.
The author mentioned in one paragraph: "I am less happy that EN 1714 permits testing of welds from one surface. One valuable lesson I have learned in my career is "the shortest distance between two points is a straight line". I believe it is short-sighted to think that a full skip scan from one surface is as effective as a half skip from both surfaces."

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