BS EN ISO 19285:2017
BSI Standards Publication
Non-destructive testing of welds — Phased array ultrasonic testing testi ng (PAUT) (PAUT) — Acceptance Acceptan ce levels levels (ISO 19285:2017)
BRITISH STANDARD
BS EN ISO 19285:2017
National foreword This British Br itish Standard St andard is i s the UK implemen implementation tation of EN ISO 19285:2017 19285:2017.. It is identical to ISO 19285:2017. The UK participation in its preparation was entrusted to Technical Committee WEE/46, Non-destructive Non-destructive testing. A list of organizations represented on this committee can be obtained on request to its secretar y. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. © The British Standards Institution 2017 Published by BSI Standards Limited 2017 ISBN 978 0 580 94510 6 ICS 25.160.40 Compliance with a British Standard c annot confer immunity from Compliance legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2017. Amendments/corrigenda issued since si nce publication Date
Tex t af fected
BRITISH STANDARD
BS EN ISO 19285:2017
National foreword This British Br itish Standard St andard is i s the UK implemen implementation tation of EN ISO 19285:2017 19285:2017.. It is identical to ISO 19285:2017. The UK participation in its preparation was entrusted to Technical Committee WEE/46, Non-destructive Non-destructive testing. A list of organizations represented on this committee can be obtained on request to its secretar y. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. © The British Standards Institution 2017 Published by BSI Standards Limited 2017 ISBN 978 0 580 94510 6 ICS 25.160.40 Compliance with a British Standard c annot confer immunity from Compliance legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2017. Amendments/corrigenda issued since si nce publication Date
Tex t af fected
BS EN ISO 19285:2017
EN ISO 19285
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
September 2017
ICS 25.160.40
English Version
Non-destructive testing of welds - Phased array ultrasonic testing (PAUT) - Acceptance levels (ISO 19285:2017) Essais non destructifs des assemblages assemblages soudés Technique ultrasons multi-éléments (PAUT) - Niveaux d'acceptation (ISO 19285:2017)
Zerstörungsfreie Prüfung von Schweißverbindungen Ultraschallprüfungen Ultraschallprüfungen mit Phased-Arrays (PAUT) Zulässigkeitsgrenzen Zulässigkeitsgrenzen (ISO ( ISO 19285:2017)
This European Standard was approved by CEN on 4 June 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN
All rights rights of exploitation in any form and by any means reserved reserved worldwide for CEN national Members.
Ref. No. EN ISO 19285:2017 E
BS EN ISO 19285:2017
EN ISO 19285:2017 (E)
European foreword This document (EN ISO 19285:2017) has been prepared by Technical Committee ISO/TC 44 “Welding and allied processes” in collaboration with Technical Committee CEN/TC 121 “Welding and allied processes” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 2018, and conflicting national standards shall be withdrawn at the latest by March 2018. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice
The text of ISO 19285:2017 has been approved by CEN as EN ISO 19285:2017 without any modification.
3
BS EN ISO 19285:2017
ISO 19285:2017(E)
Contents
Page
Foreword ........................................................................................................................................................................................................................................ iv 1
Scope ................................................................................................................................................................................................................................. 1
2
Normative references ...................................................................................................................................................................................... 1
3
Terms and definitions ..................................................................................................................................................................................... 1
4
Symbols .......................................................................................................................................................................................................................... 1
5
Acceptance levels ................................................................................................................................................................................................. 2
6
Evaluation of indications ............................................................................................................................................................................. 2
7
Determination of length and height ................................................................................................................................................. 2 7.1 General ........................................................................................................................................................................................................... 2 7.2 Determination of length .................................................................................................................................................................. 2 7.3 Determination of height .................................................................................................................................................................. 2 7.3.1 General...................................................................................................................................................................................... 2 7.3.2 Using diffracted signals .............................................................................................................................................. 2 7.3.3 Using other signals ......................................................................................................................................................... 3
8
Determination of length and maximum amplitude ......................................................................................................... 3
9
Acceptance criteria based on length and height .................................................................................................................. 3 9.1 General ........................................................................................................................................................................................................... 3 9.2 Single indications .................................................................................................................................................................................. 3 9.2.1 Acceptance criteria for level 1 .............................................................................................................................. 3 9.2.2 Acceptance criteria for level 2 .............................................................................................................................. 3 9.2.3 Acceptance criteria for level 3 .............................................................................................................................. 4 9.3 Cumulative length of indications. ............................................................................................................................................ 4 9.3.1 General...................................................................................................................................................................................... 4 9.3.2 For each single set-up .................................................................................................................................................. 4 9.3.3 Combining set-ups. ......................................................................................................................................................... 5 9.4 Grouping of indications ................................................................................................................................................................... 5 9.5 Point-like indications......................................................................................................................................................................... 6
10
Acceptance criteria based on length and amplitude ....................................................................................................... 6 10.1 General ........................................................................................................................................................................................................... 6 10.2 Longitudinal indications. ................................................................................................................................................................ 6 10.3 Transverse indications ..................................................................................................................................................................... 6 10.4 Grouping of indications ................................................................................................................................................................... 6 10.5 Cumulative length of indications. ............................................................................................................................................ 7 10.5.1 General...................................................................................................................................................................................... 7 10.5.2 For each single set-up .................................................................................................................................................. 8 10.5.3 Combined set-up .............................................................................................................................................................. 8
Annex A (normative) Levels. .......................................................................................................................................................................................... 9 Annex B (normative) Fixed amplitude level technique..................................................................................................................22
© ISO 2017 – All rights reserved
iii
BS EN ISO 19285:2017
ISO 19285:2017(E)
Foreword 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 technical 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 electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). 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 identifying any or all such patent rights. Details of any patent rights identiied during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the voluntary nature of standards, the meaning of ISO speciic terms and expressions related to conformity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html. This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee SC 5, Testing and inspection of welds. Requests for oficial interpretations of any aspect of this document should be directed to the Secretariat of ISO/TC 44/SC 5 via your national standards body. A complete listing of these bodies can be found at www.iso.org.
iv
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
INTERNATIONAL STANDARD
ISO 19285:2017(E)
Non-destructive testing of welds — Phased array ultrasonic testing (PAUT) — Acceptance levels 1 Scope This document speciies acceptance levels for the phased array ultrasonic testing technique (PAUT) of full penetration welds in ferritic steels of minimum thickness of 6 mm which correspond to the quality levels of ISO 5817. These acceptance levels are applicable to indications classiied in accordance with ISO 13588.
2
Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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 5577, Non-destructive testing — Ultrasonic testing — Vocabulary ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) — Quality levels for imperfections ISO 11666, Non-destructive testing of welds — Ultrasonic testing — Acceptance levels ISO 13588, Non-destructive testing of welds — Ultrasonic testing — Use of automated phased array technology ISO 15626, Non-destructive testing of welds — Time-of-light diffraction technique (TOFD) — Acceptance le vels ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and assessment 3
Terms and definitions
For the purposes of this document, the terms and deinitions given in ISO 5577 and ISO 13588 apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at http://www.iso.org/obp — IEC Electropedia: available at http://www.electropedia.org/
4 Symbols h
height
hg
sum of the heights of the individual indications plus the distance between them
l
length
l g
sum of the lengths of the individual indications plus the distance between them
t
thickness
© ISO 2017 – All rights reserved
1
BS EN ISO 19285:2017
ISO 19285:2017(E)
5 Acceptance levels For the evaluation, three different acceptance levels are deined. The relation between these acceptance levels and the quality levels as mentioned in ISO 5817 are given in Table 1. Table 1 — Related levels for phased array ultrasonic testing Quality level according to ISO 5817
Testing level according to ISO 13588
Acceptance level according to this document
C, D
A
3
B
B
2
By agreement
C
1
Special application
D
By agreement
NOTE Acceptance criteria for acceptance level 1 are only speciied for evaluation based on length and height.
6 Evaluation of indications Indications detected when applying ISO 13588 shall be evaluated as speciied in the test procedure either by: a)
length and height, then Clause 7 and Clause 9 shall be applied;
b)
or by length and maximum amplitude, then Clause 8 and Clause 10 shall be applied.
7 Determination of length and height 7.1
General
The size of a discontinuity is determined by its length and height.
7.2
Determination of length
The length of an indication shall be measured as described in ISO 11666, using the focal law which provides the maximum amplitude. If TOFD is used, the length of an indication shall be measured as described in ISO 15626. In any other case, testing level D of Table 1 is applicable.
7.3 7.3.1
Determination of height General
For indications displaying varying height along their length, the height shall be determined at the scan position of maximum extent. 7.3.2
Using diffracted signals
If diffracted signals are observed, they shall be used to determine height. The height is determined using either: — two diffracted signals observed from the same discontinuit y (upper and lower tip); — one diffracted signal and a surface signal observed from the same discontinuity; — one diffracted signal and the known wall thickness for root connected discontinuities; 2
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
— one diffracted signal in relation to the surface for a surface breaking discontinuity. If TOFD is used, the height shall be measured as described in ISO 15626. 7.3.3
Using other signals
In case a height cannot be measured using diffracted signals, then the determination can be based on: — amplitudes using the reference levels as described in ISO 11666. Other sizing techniques may be used (TCG, DGS, 6 dB drop); — the time-of-light of relections (e.g. hollow root, mismatch); — the time-of-light of mode converted signals.
8
Determination of length and maximum amplitude
The length of an indication shall be determined by measuring the distance along the weld over which the echo amplitude is above the evaluation level using the ixed amplitude level technique speciied in Annex B. Alternative techniques for measuring indication length may be used when speciied.
9
Acceptance criteria based on length and height
9.1
General
When indications are detected, length and height are determined in accordance with 7.2 and 7.3. Indications shall be evaluated according to their acceptance level and the acceptance criteria listed in this clause. For welds joining two different thicknesses, the thinner of those two is leading for the acceptance criteria.
9.2 9.2.1
Single indications Acceptance criteria for level 1
Acceptance criteria for level 1 are given in Table 2. Table 2 — Acceptance criteria for level 1 Maximum allowable length ( l max ) if h < h2 or h3
Maximum allowable height (h1)
Surface breaking
Embedded
when l > l max
l max
h3
h2
h1
mm
mm
mm
mm
6 mm < t ≤ 15 mm
0,75t
1,5
2
1
15 mm < t ≤ 50 mm
0,75t
2
3
1
50 mm < t ≤ 100 mm
40
2,5
4
2
t >
50
3
5
2
Thickness range
100 mm
9.2.2
Acceptance criteria for level 2
Acceptance criteria for level 2 are given in Table 3. © ISO 2017 – All rights reserved
3
BS EN ISO 19285:2017
ISO 19285:2017(E)
Table 3 — Acceptance criteria for level 2 Maximum allowable length ( l max ) if h < h2 or h3
Maximum allowable height (h1)
Surface breaking
Embedded
when l > l max
l max
h3
h2
h1
mm
mm
mm
mm
6 mm < t ≤ 15 mm
t
2
2
1
15 mm < t ≤ 50 mm
t
2
4
1
50 mm < t ≤ 100 mm
50
3
5
2
t >
60
4
6
3
Thickness range
100 mm
9.2.3
Acceptance criteria for level 3
Acceptance criteria for level 3 are given in Table 4. Table 4 — Acceptance criteria for level 3 Maximum allowable length ( l max ) if h < h2 or h3
Maximum allowable height (h1)
Surface breaking
Embedded
when l > l max
l max
h3
h2
h1
mm
mm
mm
mm
6 mm < t ≤ 15 mm
1,5t (max. 20)
2
2
1
15 mm < t ≤ 50 mm
1,5t (max. 60)
2,5
4,5
2
50 mm < t ≤ 100 mm
60
4
6
3
t >
75
5
8
4
Thickness range
100 mm
9.3 9.3.1
Cumulative length of indications General
Point-like indications are not considered to determine total length. The cumulative length of all individually acceptable indications above recording level is given as the sum of lengths of both single indications and linearly aligned indications of combined length within a given section of weld length. 9.3.2
For each single set-up
For wall thickness ≤50 mm, the sum of the lengths of the individually acceptable indications measured along the weld over a length of 12t shall be ≤: — for acceptance level 1: 3,5t with a maximum of 150 mm; — for acceptance level 2: 4,0t with a maximum of 200 mm; — for acceptance level 3: 4,5t with a maximum of 225 mm. For wall thickness >50 mm, the sum of the lengths of the individual indications measured along the weld over the total length of the weld shall be ≤: — for acceptance level 1: 10 % of the weld length with a maximum of 500 mm;
4
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
— for acceptance level 2: 10 % of the weld length with a maximum of 600 mm; — for acceptance level 3: 10 % of the weld length wit h a maximum of 700 mm. 9.3.3
Combining set-ups
In addition to 9.3.2, when using two set-ups according to testing level C in ISO 13588 and additional indications are found, the maximum total length for combined indications shall not exceed 1,5 times the maximum length stated in 9.3.2.
9.4
Grouping of indications
Point-like indications are not considered for grouping. Grouping of indications is based on the size and the separation of individual indications. The length and the size of a group shall not be used for further grouping. A group of indications shall be considered as a single indication if — the distance between two individual indications along the weld is less than the length of the longer indication, and — the distance between two individual indications in thickness direction of the weld is less than the height of the higher indication. For acceptance or rejection, grouped indications are treated as single indications according to 9.2.
Key 1, 2, 3 simple representation of three indications h
maximum height of indications 1, 2, 3
l
maximum length of indications 1, 2, 3
hg
t otal height of grouped indications
l g
total length of grouped indications
Figure 1 — Dimensions of grouped indications For a grouped indication, the total height, hg , is deined as the sum of the heights of the individual indications plus the distance between them (see Figure 1). For a grouped indication, the total length, l g , is deined as the sum of the lengths of the individual indications plus the distance between them (see Figure 1). Indications 2 and 3 shown in Figure 1 shall be treated as a single indication because their separation in x-direction is smaller than l and their separation in z -direction is smaller than h. Indication 1 is not included in the group because the separation in t he thickness direction is larger than h.
© ISO 2017 – All rights reserved
5
BS EN ISO 19285:2017
ISO 19285:2017(E)
9.5
Point-like indications
Point-like indications have no signiicant extent in any direction. They may originate from diffraction or relection. The maximum number (N ) of point-like indications in any 150 mm of weld length shall not exceed the value given by Formula (1): N =
1,2t
(1)
where N
is rounded to the higher integer;
t
is the thickness given in millimetres.
10 Acceptance criteria based on length and amplitude 10.1 General When indications are detected, length and maximum amplitude are determined in accordance with Clause 8. Indications shall be evaluated according to their acceptance level and the acceptance criteria listed in this clause. For welds joining two different thicknesses, the thinner of those two is leading for the acceptance criteria.
10.2 Longitudinal indications Table A.1 gives information on the techniques used for the evaluation of indications and the related evaluation and acceptance levels. Table A.2 speciies the reference levels for acceptance levels 2 and 3 for technique 2 using angle-beam scanning with transverse waves. Table A.3 speciies the reference levels for acceptance levels 2 and 3 for technique 2 using straight-beam scanning with longitudinal waves. — For techniques 1 (side-drilled holes) and 3 (rectangular notch), see Figure A.1 to Figure A.4. — For techniques 2 [lat-bottomed holes (disk-shaped relectors)] and 4 (tandem technique), see Figure A.5 to Figure A.10. Any indication with an amplitude below the acceptance level but with a length (above evaluation level) exceeding t , for the thickness range of 6 mm ≤ t < 15 mm, or t /2 or 20 mm, whichever is larger, for all other thickness ranges, shall be subject to further testing. This requires the use of additional probe angle(s), and, if speciied, the tandem technique. The inal evaluation shall be based on the maximum echo amplitude and length measured.
10.3 Transverse indications When detection of transverse indications is speciied, the acceptance levels stated in 10.2 apply.
10.4 Grouping of indications Grouping is based on the length and the separation of individually acceptable indications having amplitudes above the recording level. The length of a group shall not be used for further grouping. For evaluation, a group of indications shall be considered as a single one if: a) 6
the dist ance, d x , is less than twice the length of the longer indication (see Figure 2); © ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
b) the distance, d y, is less than half of the thickness but not more than 10 mm; c)
the distance, d z , is less than half of the thickness but not more than 10 mm.
The combined length is as shown in Formula (2): l 12 = l 1 + l 2 + d x
(2)
See Figure 3. The combined length, l 12, and the larger maximum amplitude of the two indications shall then be assessed against the applicable acceptance levels given in Table A.1.
Key d x, d y, d z distances in the x -, y - and z -directions, respectively l n
length of individual indications, where n = 1…3
Figure 2 — Simple representation of grouped indications in a sketch of a weld
Key d x
distance in the x -direction
l 1, l 2 length of individual indications l 12
combined length
Figure 3 — Lengt h of a group of indications
10.5 Cumulative length of indications 10.5.1 General The cumulative length of all individually acceptable indications above recording level is calculated within a speciied section of weld length, l w, as the sum of lengths of both single indications and linearly aligned indications (see Figure 4).
© ISO 2017 – All rights reserved
7
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key l c
cumulative length
l c = l 2 + l 3 + l 45 + l 6 l w
weld length
l n
length of individual indications, where n = 1…7
Figure 4 — Cumulative length of indications
10.5.2 For each single set-up For any section of weld length, l w = 6t , the maximum cumulative length, l c, of all individually acceptable indications above the recording level shall not exceed 20 % of l w for acceptance level 2 or 30 % of l w for acceptance level 3. 10.5.3 Combined set-up In addition to 10.5.2, when using two set-ups according to testing level C in ISO 13588 and additional indications are found, the maximum total length for combined indications shall not exceed 1,5 times the maximum length stated in 10.5.2.
8
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
Annex A (normative) Levels
Key 1
reference level
2
acceptance level 2
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.1 — Levels for techniques 1 and 3 for thicknesses 6 mm to 15 mm — Acceptance level 2
© ISO 2017 – All rights reserved
9
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 3
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.2 — Levels for techniques 1 and 3 for thicknesses 6 mm to 15 mm — Acceptance level 3
10
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 2
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.3 — Levels for technique 1 for thicknesses 15 mm to 100 mm — Acceptance level 2
© ISO 2017 – All rights reserved
11
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 3
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.4 — Levels for technique 1 for thicknesses 15 mm to 100 mm — Acceptance level 3
12
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 2
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.5 — Levels for technique 2 for thicknesses 6 mm to 15 mm — Acceptance level 2
© ISO 2017 – All rights reserved
13
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 3
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.6 — Levels for technique 2 for thicknesses 6 mm to 15 mm — Acceptance level 3
14
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 2
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.7 — Levels for technique 2 for thicknesses 15 mm to 100 mm — Acceptance level 2
© ISO 2017 – All rights reserved
15
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 2
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.8 — Levels for technique 4 for thicknesses 15 mm to 100 mm — Acceptance level 2
16
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 3
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.9 — Levels for technique 2 for thicknesses 15 mm to 100 mm — Acceptance level 3
© ISO 2017 – All rights reserved
17
BS EN ISO 19285:2017
ISO 19285:2017(E)
Key 1
reference level
2
acceptance level 3
3
recording level
4
evaluation level
H
amplitude in dB
l
indication length
t
thickness
Figure A.10 — Levels for technique 4 for thicknesses 15 mm to 100 mm — Acceptance level 3
18
© ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
) 3 L A ( 3 l e v e l e c n a t p e c c A
4 d n a 3 , 2 , 1 ) s 2 e L u A q ( i n 2 l e h c v e e t l r e o c n f t 3 a d p c n e c a A 2 s l e v e l e c n a t p e c c A — l e 1 . v e A l e n l o b i a t a T l u
m : : m t t 0 : : t ≤ ≤ B : t 0 5 B B B l B : t d , d l d t d 5 1 0 , 0 < d > > 0 < ≤ 4 < 4 t 2 l 6 ≤ t l 0 1 5 t 5 – – r r H l + , o 0 r + , + ≤ r 0 o 0 0 0 F 0 o 0 o H r H H F r H F m F H o o m F F
—
5 1
m m 5 1 < t
≤ m m 6
: t
: t B d ≤ 0 > 6 l l r H r – o o 0 F F H
: : t B t d ≤ 6 > 0 l l r + r H o 0 o F H F
: t
: t B d ≤ 0 > 6 l l r H r – o o 0 F F H
m : : m t t : 0 : t t ≤ ≤ : B B : 0 5 B B t , d l , l d t d 5 1 0 0 < 0 > d > 0 < ≤ 0 < t 6 l t l 4 ≤ 6 5 t 5 – r 1 – l + l H , , H r – ≤ r 0 0 o 0 r 0 o 0 0 F F o r H H o H r H m F F o o m F F
—
5 1
m m 5 1 < t
≤ m m 6
3 L A r o f
B : : t B t d d ≤ > 0 l 4 l 1 r – r – o 0 o 0 F H F H
B d 0 1 –
0
H
a v E 2 L A r o f
B d 4 1 –
o e t ) u g 0 n 4 q i i 6 7 n d r h o 1 c c O e S T c a I (
) s e l o h d e 1 l l i r d e d i s (
0
H
© ISO 2017 – All rights reserved
: : t B t B d d ≤ 2 > 4 l l r + r – o 0 o 0 F H F H
h t i w r o 3 B e . 2 d c . A n 4 a A l e – d e b l r 0 o b a H c a T c T a n i h t i w r o 3 B e . 2 d c . A n 8 a A l e – d l e b 0 r o b a H c a T c T a n i s e l o h d ] ) s d e e p a r o h t 2 m s c o t e l t k f s o i e b - d ( r t a l f [
: t : t ≤ B : B B 5 , d l d t d 0 < 0 > 4 ≤ 4 t 1 l 1 l – 5 , – r – o 0 r 0 0 0 o H r H F H F o F
—
: t : t ≤ B : B B 5 , d l d t d 0 < 4 > 8 ≤ 8 t 1 l 1 l – 5 , – r – o 0 r 0 0 0 F o H r H H F o F
B : : t B t d d ≤ > 0 l 4 l 1 r – r – o 0 o 0 F H F H
—
B d 0 1 –
B d 8 1 –
H
H
B d 4 1 –
B d 2 2 –
H
H
) h c t o n r a 3 l u g n a t c e r (
) e u q i n h c 4 e t m e d n a t (
0
0
0
0
. s l e v e l e c n a t p e c c a g n i d n o p s e r r o c e h t w o l e b B l . d e 4 v e e r l a e s c n l e e v r e e f l g e r n e i h d r t s o c i e 0 R H 1 2 E E T T O O N N
19
BS EN ISO 19285:2017
ISO 19285:2017(E)
m m m m , 0 , 3 0 3 3 L = = m A R R m S S D D 0 D D 0 1 <
s e v a w e s r e v s ≤ n a m m m r t m m m 0 2 0 h , 0 , t 4 i L 3 3 A = = w R R g S S D D n i D D n n a c s m m m l , m m a a i e r 5 , , 0 3 b 2 2 - e t L e a A = = l R R g m m S S n t m D D a n D D 0 e g r 4 n a < i p s f u o ≤ 2 s m m m e s e m m m u n 5 5 , 0 , 2 q 1 i k 2 2 c L i n h A = = h R R c T S S e D D t D D r o f 3 d n m a m 2 5 , 3 s 1 l L — e m A = v R m e S l 5 D 1 e D c < n a ≤ t . p m r m e o m c m t c c 5 6 2 e , l a 1 L — e r = r A o f R d S e s D p l e D a h v s e l k s ) i e z d c H e n h M e t ( r f y e o f c r e e n t e R e 5 0 u , , m q 5 2 — a i e o r 2 t d t o f . e 5 e A , h , 0 b 1 3 t e s o l i r b R p S a D l T a D t
t
t
t
n i m o N
20
E T O N © ISO 2017 – All rights reserved
BS EN ISO 19285:2017
ISO 19285:2017(E)
m m
s m m e , 0 , 3 0 v a L 3 3 m A = = w R R l m S S a D D 0 n 0 D D i 1 d < u t i ≤ g n m m m o l m m m 0 2 0 h , 0 , t 4 i L 3 3 A = = w R R g S S D D n i D D n n a c s m m m l , m m a a e i 5 , , 0 3 2 b r 2 L e t = = h t a m A R R g S S i m m D D a t 0 D D r n 4 t e < s r g a p ≤ n f i s o m m m u s m m m 2 s 5 e 5 , , 0 e n 1 2 2 2 L k u c A = = q i i R R S S n h D D T h D D c e t r o f m 3 m d 0 n , 3 a L — 2 = 2 m A R s S l m D e 5 D v 1 e l < e c ≤ n m . m a t m r m o p 0 6 , t c e 2 e c L — 2 l c = e A a R r r S d D e o f D p a s l h s e v k ) s z e i l d H e e M c h ( t n f y e o c r r n e e e f t e u e 5 0 , , q R 2 5 m e a i r o f t d t o — e e 5 3 , h , 0 b . 1 3 t o s A i r e p R l S l D b a D a n i T E t
t
t
t
m o N
T O N
© ISO 2017 – All rights reserved
21
BS EN ISO 19285:2017
ISO 19285:2017(E)
Annex B (normative) Fixed amplitude level technique
The technique measures the lateral dimensions of an indication over which the echo is equal to or greater than the evaluation level. To make a measurement, the beam is scanned over the indications, and the probe position and beam path range, at which the echo has fallen to the evaluation level, are noted (positions 1 and 2 in Figure B.1). The lateral dimension, l , is then determined by the distance between the positions 1 and 2.
Key l
measured lateral dimension of indication
1, 2
positions where indication amplitudes are equal to the evaluation level
a
Maximum echo.
b
Evaluation level.
Figure B.1 — Fixed amplitude level technique using the beam axis
22
© ISO 2017 – All rights reserved
This page deliberately left blank