ISO 16811-2012 Non-destructive testing - Ultrasonic testing - Sensitivity and range setting《无损检测 超声波检测 敏感性和范围设置》.pdf

1、 Reference number ISO 16811:2012(E) ISO 2012INTERNATIONAL STANDARD ISO 16811 First edition 2012-04-01 Non-destructive testing Ultrasonic testing Sensitivity and range setting Essais non destructifs Contrle par ultrasons Rglage de la sensibilit et de la base de temps ISO 16811:2012(E) COPYRIGHT PROTE

2、CTED DOCUMENT ISO 2012 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs me

3、mber body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2012 All rights reservedISO 16811:2012(E) ISO 2012 All rights reserved iiiContents Pa

4、ge Foreword .v 1 Scope1 2 Normative references1 3 General.1 3.1 Quantities and symbols1 3.2 Test objects, reference blocks and reference reflectors.1 3.3 Categories of test objects.1 3.4 Contouring of probes2 3.4.1 Longitudinally curved probes 3 3.4.2 Transversely curved probes3 3.4.3 Concave scanni

5、ng surface.4 4 Determination of probe index and beam angle 4 4.1 General.4 4.2 Flat probes.4 4.2.1 Calibration block technique .4 4.2.2 Reference block technique.4 4.3 Probes curved longitudinally .4 4.3.1 Mechanical determination4 4.3.2 Reference Block Technique .6 4.4 Probes curved transversely .6

6、 4.4.1 Mechanical determination6 4.4.2 Reference block technique.7 4.5 Probes curved in two directions8 4.6 Probes for use on materials other than non-alloy steel 9 5 Time base setting 9 5.1 General.9 5.2 Reference blocks and reference reflectors.9 5.3 Straight beam probes10 5.3.1 Single reflector t

7、echnique10 5.3.2 Multiple reflector technique10 5.4 Angle beam probes .10 5.4.1 Radius technique.10 5.4.2 Straight beam probe technique .10 5.4.3 Reference block technique.10 5.4.4 Contoured probes.10 5.5 Alternative range settings for angle beam probes 11 5.5.1 Flat surfaces11 5.5.2 Curved surfaces

8、11 6 Sensitivity setting and echo height evaluation 13 6.1 General.13 6.2 Angle of impingement.13 6.3 Distance Amplitude Curve (DAC) technique 13 6.3.1 Reference blocks.13 6.3.2 Preparation of a Distance Amplitude Curve .14 6.3.3 Evaluation of signals using a Distance Amplitude Curve.15 6.3.4 Evalua

9、tion of signals using a reference height15 6.4 Distance Gain Size (DGS) technique .16 6.4.1 General.16 6.4.2 Reference blocks.18 6.4.3 Use of DGS diagrams18 6.4.4 Restrictions on use of the DGS technique due to geometry 20 Introduction .vi ISO 16811:2012(E) iv ISO 2012 All rights reserved6.5 Transfe

10、r correction20 6.5.1 General20 6.5.2 Fixed path length technique .20 6.5.3 Comparative technique.21 6.5.4 Compensation for local variations in transfer correction .22 Annex A (normative) Quantities and symbols .23 Annex B (normative) Reference blocks and reference reflectors 26 Annex C (normative) D

11、etermination of sound path distance and impingement angle in concentrically curved objects 29 C.1 Impingement angle29 C.2 Sound path when scanning from the outer (convex) surface: .29 C.2.1 Full skip30 C.2.2 Half skip30 C.3 Soundpath when scanning from the inner (concave) surface:.31 C.3.1 Full skip

12、31 C.3.2 Half skip32 Annex D (informative) General DGS diagram.33 D.1 Distance33 D.2 Gain.33 D.3 Size34 Annex E (informative) Determination of contact transfer correction factors35 E.1 General35 E.2 Measurement35 E.3 Evaluation.35 Bibliography 38 ISO 16811:2012(E) ISO 2012 All rights reserved vForew

13、ord ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a techni

14、cal committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of e

15、lectrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to

16、the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for i

17、dentifying any or all such patent rights. ISO 16811 was prepared by Technical Committee ISO/TC 135, Non-destructive testing, Subcommittee SC 3, Ultrasonic testing. ISO 16811:2012(E) vi ISO 2012 All rights reservedIntroduction This International Standard is based on EN 583-2:2001, Non-destructive tes

18、ting Ultrasonic examination Part 2: Sensitivity and range setting. The following International Standards are linked. ISO 16810, Non-destructive testing Ultrasonic testing General principles ISO 16811, Non-destructive testing Ultrasonic testing Sensitivity and range setting ISO 16823, Non-destructive

19、 testing Ultrasonic testing Transmission technique ISO 16826, Non-destructive testing Ultrasonic testing Examination for discontinuities perpendicular to the surface ISO 16827, Non-destructive testing Ultrasonic testing Characterization and sizing of discontinuities ISO 16828, Non-destructive testin

20、g Ultrasonic testing Time-of-flight diffraction technique as a method for detection and sizing of discontinuities 11 Scope This International Standard specifies the general rules for setting the timebase range and sensitivity (i. e. gain adjustment) of a manually operated ultrasonic flaw detector wi

21、th A-scan display in order that reproducible measurements may be made of the location and echo height of a reflector. It is applicable to techniques employing a single contact probe with either a single or twin transducers, but excludes the immersion technique and techniques employing more than one

22、probe. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 2400, Non-destr

23、uctive testing Ultrasonic testing Specification for calibration block No. 1 ISO 7963, Non-destructive testing Ultrasonic testing Specification for calibration block No. 2 EN 12668-3, Non-destructive testing Characterization and verification of ultrasonic examination equipment Part 3: Combined equipm

24、ent 3 General 3.1 Quantities and symbols A full list of the quantities and symbols used throughout this International Standard is given in Annex A. 3.2 Test objects, reference blocks and reference reflectors Requirements for geometrical features of test objects, reference blocks and reference reflec

25、tors in general are contained in Annex B. 3.3 Categories of test objects The requirements for range and sensitivity setting will depend on the geometrical form of the test object. Five categories of test objects are defined in Table 1. INTERNATIONAL STANDARD ISO 16811:2012(E)Non-destructive testing

26、Ultrasonic testing Sensitivity and range setting ISO 2012 All rights reserved2 Table 1 Categories of test objects Class Feature Section in x-direction section in y-direction 1 Plane parallel surfaces (e. g. plate/sheet) 2 Parallel, uniaxially curved surfaces (e. g. tubes) 3 Parallel surfaces curved

27、in more than one direction (e. g. dished ends) 4 Solid material of circular cross section (e. g. rods and bars) 5 Complex shapes (e. g. nozzles, sockets) 3.4 Contouring of probes Contouring of the probe shoe, for geometry categories 2 to 5, may be necessary to avoid probe rocking, i.e. to ensure goo

28、d, uniform, acoustic contact and a constant beam angle in the test object. Contouring is only possible with probes having a hard plastic stand-off (normally twin-transducer straight beam probes or angle beam probes with wedges). The following conditions for the different geometric categories exist (

29、see Table 1 and Figure 1): category 1: No probe contouring necessary for scanning in either x- or y-direction; categories 2 and 4: scanning in x-direction: Probe face longitudinally curved, scanning in y-direction: Probe face transversely curved; categories 3 and 5: scanning in either x- or y-direct

30、ion: Probe face longitudinally and transversely curved. ISO 16811:2012(E) ISO 2012 All rights reserved3The use of contoured probes necessitates setting the range and sensitivity on reference blocks contoured similar to the test object, or the application of mathematical correction factors. When usin

31、g equations (1) or (2), problems due to low energy transmission or beam misalignment are avoided. 3.4.1 Longitudinally curved probes 3.4.1.1 Convex scanning surface For scanning on convex surfaces the probe face shall be contoured when the diameter of the test object, D obj , is below ten times the

32、length of the probe shoe, l ps , (see Figure 1): ps obj 10 l D (1) 3.4.1.2 Concave scanning surface On a concave scanning surface the probe face shall always be contoured, unless adequate coupling can be achieved due to very large radii of curvature. 3.4.2 Transversely curved probes 3.4.2.1 Convex s

33、canning surface For scanning on convex surfaces the probe face shall be contoured when the diameter of the test object, D obj , is below ten times the width of the probe shoe, w ps , (see Figure 1): ps obj 10 w D (2) Key 1 Transversely curved 2 Longitudinally curved Figure 1 Length, l ps , and width

34、, w ps , of probe shoe in direction of curvature of the test object ISO 16811:2012(E) ISO 2012 All rights reserved4 3.4.2.2 Concave scanning surface On a concave scanning surface the probe face shall always be contoured, unless adequate coupling can be achieved due to very large radii of curvature 3

35、.4.3 Concave scanning surface The probe face shall fulfil the requirements of 3.4.1 and 3.4.2. 4 Determination of probe index and beam angle 4.1 General For straight beam probes there is no requirement to measure probe index and beam angle as it is assumed that the probe index is in the centre of th

36、e probe face and the angle of refraction is zero degrees. When using angle probes, these parameters shall be measured in order that the position of a reflector in the test object can be determined in relation to the probe position. The techniques and reference blocks employed depend on the contourin

37、g of the probe face. Measured beam angles depend on the sound velocity of the reference block used. If the block is not made of non-alloy steel its velocity shall be determined and recorded. 4.2 Flat probes 4.2.1 Calibration block technique Probe index and beam angle shall be determined using Calibr

38、ation Block No. 1 or Calibration Block No. 2 according to the specifications given in ISO 2400 or ISO 7963 respectively, depending on the size of the probe. 4.2.2 Reference block technique An alternative technique using a reference block containing at least 3 side-drilled holes as given in EN 12668-

39、 3 may be used. 4.3 Probes curved longitudinally 4.3.1 Mechanical determination Before contouring the probe face, the probe index and beam angle shall be measured as described in 4.2.1. The incident angle at the probe face ( d ) shall be calculated from the measured beam angle ( ) and a line, origin

40、ating from the probe index and parallel to the incident beam, shall be marked on the side of the probe, as shown in Figure 2. The incident angle is given by equation 3: = sin c c arcsin t d d(3) where c dis the longitudinal wave velocity in the probe wedge (normally 2730 m/s for acrylic glass) c tis

41、 the transverse wave velocity in the test object (3255 m/s 15 m/s for non-alloy steel). ISO 16811:2012(E) ISO 2012 All rights reserved5After contouring, the probe index will have moved along the marked line, and its new position can be measured by mechanical means directly on the probe housing, as s

42、hown in Figure 2. The beam angle shall be determined by maximizing the echo from a side-drilled hole satisfying the conditions given in annex B. The beam angle may then be measured directly on the test object, on the reference block, or on a scale drawing. See Figure 3. Alternatively, the beam angle

43、 may be determined by calculation on the basis of the sound path length measured on the reference block by mechanical means, using equation (4). This may be accomplished together with the range setting as described in 5.4.4. () () + + + + = 2 / 2 / arccos SDH Obj Obj SDH 2 2 2 SDH D s D tD sD t s D

44、(4) The symbols used in this equation are illustrated in Figure 3. The radius of curvature of the surface used for the calibration shall be within 10 % of that of the test object. Key 1 Marked line for index shift 2 Index point after contouring 3 Index point before contouring Figure 2 Determination

45、of index shift for longitudinally curved probes ISO 16811:2012(E) ISO 2012 All rights reserved6 Figure 3 Determination of beam angle for a longitudinally contoured probe 4.3.2 Reference Block Technique This is similar to that referenced in 4.2.2, except that the test block shall have a radius of cur

46、vature within 10% of that of the test object. 4.4 Probes curved transversely 4.4.1 Mechanical determination Before contouring the probe face the probe index and beam angle shall be measured as described in 4.2. After contouring, either i) a line representing the incident beam, originating from the p

47、robe index, shall be marked on the side of the probe. The new position of the probe index shall be measured on the side of the probe as shown in Figure 4; ii) the shift in probe index position ( x) shall be calculated using equation 5: ) ( tan d g x = (5) The symbols in this equation are illustrated

48、 in Figure 4. For acrylic glass wedges ( c d =2730 m/s) and non-alloy steel test objects ( c t =3255 m/s) the shift in the probe index position ( x), for the three most commonly used beam angles, shall be read from Figure 5 in relation to the depth of contouring (g). The beam angle should not change

49、 during contouring. However, if it is not known, or there is any variation in the depth of contouring along the length of the probe, it shall be measured on a suitably contoured reference block using a side drilled hole satisfying the conditions given in Annex B. The beam angle shall be determined by: ISO 16811:2012(E) ISO 2012 All rights reserved7iii) drawing a straight line between the hole and the probe