kSIST FprEN 12680-4:2026
(Main)Founding - Ultrasonic testing - Part 4: Phased array ultrasonic testing of steel castings
- Abstract
This document specifies requirements for phased array ultrasonic examination of steel castings with low ultrasonic attenuation. It is applicable to ferritic, bainitic and martensitic microstructures. It specifies the registration levels and acceptance criteria.
This document is applicable to the ultrasonic examination of steel castings with a wall thickness of 600 mm or less.
For higher wall thicknesses, special agreements apply regarding the test procedure and recording levels.
This document does not apply to austenitic steels and cast irons, lamellar graphite and spheroidal cast irons and welded assemblies. For other ferrous materials, this document gives guidance. The registration levels and acceptance criteria are to be adapted.
In this document, phased array is used both for phased array technique and TFM technique.
- Status
- Not Published
- Public Enquiry End Date
- 30-Jul-2025
- Technical Committee
- IFEK - Ferrous metals
- Current Stage
- 5020 - Formal vote (FV) (Adopted Project)
- Start Date
- 23-Jul-2026
- Due Date
- 10-Sep-2026
- Completion Date
- 24-Jul-2026
kSIST FprEN 12680-4:2026 is a draft European standard from CEN, published by SIST, for phased array ultrasonic testing of steel castings. It specifies how to examine steel castings with low ultrasonic attenuation, including ferritic, bainitic and martensitic microstructures, and how to apply registration levels and acceptance criteria. The document uses phased array to cover both phased array technique and TFM technique.
What does kSIST FprEN 12680-4:2026 specify?
kSIST FprEN 12680-4:2026 specifies the scope, preparation, execution, interpretation and reporting of phased array ultrasonic examination for steel castings. It is organized into clauses 1 to 11, with Annex A giving informative examples of reference blocks.
The standard applies to steel castings with a wall thickness of 600 mm or less. For thicker castings, the manufacturer and customer need special agreement on the test procedure and recording levels, so the document can still be used, but not as a one-size-fits-all procedure.
It does not apply to austenitic steels, cast irons, lamellar graphite and spheroidal cast irons, or welded assemblies. For other ferrous materials, it gives guidance and says the registration levels and acceptance criteria have to be adapted.
What are the key requirements of kSIST FprEN 12680-4:2026?
Ordering and written procedure
Clause 4 requires the purchase order or inquiry to define the examination volume, the blocks to be used, access and surface conditions, the test stage, and any extra procedure requirements. This matters because phased array testing only gives comparable results when both sides have agreed what will be inspected and under what conditions.
Clause 4.3 also requires a written test procedure. That procedure has to cover the purpose, operating techniques, severity levels, qualification and training, equipment, blocks, settings and checks, scan plan, evaluation levels, acceptance or registration levels, reporting, and safety and environmental issues.
Personnel, equipment and pre-test preparation
Clause 5 requires qualified personnel with appropriate ultrasonic testing qualification in accordance with EN ISO 9712 or an equivalent foundry-sector standard. Operators also need training and practical experience in phased array technique and TFM technique, because the interpretation of images and indications depends on skill.
Clause 6 requires equipment that meets EN ISO 18563-1, EN ISO 18563-2 and EN ISO 18563-3 where applicable. The ultrasonic instrument has to generate beams suited to the part geometry, material structure and severity level, and the probe arrangement has to account for surface curvature and dead elements.
Clause 7 requires daily checking of channels, probes and cables with reference blocks, plus corrective action and re-verification if something fails. It also requires clean scanning surfaces, suitable coupling, attention to temperature, and a check that the material is suitable for phased array ultrasonic examination.
Scan plan and scanning control
Clause 7.2 requires a scan plan that identifies the scan faces, electronic scans, beam types, probe movement and overlap. In practice, this means the inspector has to show how the full volume will be covered without gaps.
For encoded systems, the mechanical scanning step depends on wall thickness, and for manual control the speed and increment have to preserve coverage and data quality. This matters because data loss or insufficient overlap can hide indications.
Clause 7.3 and 7.4 focus on geometry and surface condition. Complex shapes need careful planning, the probe base has to stay close to the surface, and the surface has to be clean enough to allow stable coupling.
Time base, sensitivity and reference blocks
Clause 8 requires time base and sensitivity to be set before each test and reset if the configuration changes. The document also calls for an echo selection gate that includes the region of interest where appropriate.
Clause 8.1.3 and 8.1.4 require sensitivity to be set for each beam and, where used, each focused beam. Transfer correction may be needed when the coupling and backwall surfaces affect the signal amplitude, so the operator has to compensate for real surface conditions rather than assuming ideal ones.
Clause 8.2 requires settings to be checked at the beginning and end of inspection, and deviations beyond the stated limits to be corrected. Clause 8.3 requires reference blocks made from acoustically similar material, with a minimum number of reflectors depending on wall thickness.
Operating modes, data and acceptance
Clause 9 states that the operating procedure depends on casting shape and the discontinuities expected, and that both sides should be examined if possible. It also requires local image recording for severity level 1, and an additional inspection of finishing welds deeper than 50 mm with inclined transverse wave imaging.
Clause 10 sets out how to assess data quality, identify true indications, classify and size relevant indications, record them, and compare them with the acceptability limits. This is the practical decision point: the operator must decide whether an indication is geometric or relevant, then record and measure it against the severity levels.
Clause 11 defines what the test report has to contain, including the casting data, scope, equipment, probes, technique, sensitivity data, discontinuity information, date, responsible person and any deviations. That makes the inspection traceable for the buyer, manufacturer and quality file.
What terms does kSIST FprEN 12680-4:2026 define?
- Ultrasonic instrument - The document uses this as a generic term for both a Phased Array instrument and a TFM instrument.
- Phased array image - A one- or two-dimensional display built from the collected phased array data.
- Phased array setup - The probe arrangement defined by probe characteristics, probe position and number of probes.
- Probe position (PP) - The position of the probe reference point relative to the part reference point.
- Region of interest (ROI) - The two- or three-dimensional test region for which the image is computed.
- Total focusing technic (TFM) - Synthetic focusing inside an ROI by processing A-scan information from transmitter-receiver combinations.
- Scan increment - The distance between successive data collection points during scanning.
- Equivalent discontinuity echo size - The smallest indication to be recorded during evaluation, usually expressed as the equivalent diameter of a side drilled hole.
Who uses kSIST FprEN 12680-4:2026?
kSIST FprEN 12680-4:2026 is used by foundries, casting manufacturers, NDT operators, inspection providers, quality managers and customers who specify ultrasonic inspection for steel castings. It is especially relevant when the casting has ferritic, bainitic or martensitic microstructure and low ultrasonic attenuation.
In practice, these users apply it when writing purchase requirements, choosing scan plans, setting up phased array equipment, qualifying personnel, evaluating indications and documenting acceptance. It is most useful when the buyer needs a common inspection method for castings with defined wall thickness and agreed severity levels.
Which standards are used with kSIST FprEN 12680-4:2026?
| Standard | What it contributes |
|---|---|
| EN 12680-1 | The series reference for steel castings for general purposes, and the source of some vocabulary and reference reflector concepts. |
| EN ISO 5577 | Vocabulary for ultrasonic testing. |
| EN ISO 9712 | Personnel qualification and certification for NDT personnel. |
| EN ISO 16810 | General principles for ultrasonic testing, including order information and coupling medium. |
| EN ISO 18563-1 | Verification of ultrasonic phased array instruments. |
| EN ISO 18563-2 | Verification of ultrasonic array probes. |
| EN ISO 18563-3 | Verification of complete ultrasonic phased array systems. |
| EN ISO 23243 | Vocabulary for ultrasonic testing with arrays. |
The foreword also places this document in the EN 12680 series with EN 12680-2 and EN 12680-3 as the other parts of the family.
What does the kSIST FprEN 12680-4:2026 document contain?
The document contains the working structure for an inspection procedure: requirements before ordering, personnel qualification, equipment, preparation before testing, time base and sensitivity settings, test operating mode, interpretation and analysis, and the test report. It also includes the normative references and a terms-and-definitions section.
Several tables support day-to-day inspection work. They cover mechanical scanning steps, ultrasonic testability, correction actions for setting deviations, minimum reference reflector counts, recommended active aperture and frequency ranges, acceptability limits, and recording levels.
The figures and annex support setup and interpretation. Figure 1 explains electronically covered area, Figure 2 divides the wall section into zones, and Annex A gives examples of reference blocks used to check coverage and sensitivity.
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Frequently Asked Questions
kSIST FprEN 12680-4:2026 is a draft published by the Slovenian Institute for Standardization (SIST). Its full title is "Founding - Ultrasonic testing - Part 4: Phased array ultrasonic testing of steel castings". This standard covers: This document specifies requirements for phased array ultrasonic examination of steel castings with low ultrasonic attenuation. It is applicable to ferritic, bainitic and martensitic microstructures. It specifies the registration levels and acceptance criteria. This document is applicable to the ultrasonic examination of steel castings with a wall thickness of 600 mm or less. For higher wall thicknesses, special agreements apply regarding the test procedure and recording levels. This document does not apply to austenitic steels and cast irons, lamellar graphite and spheroidal cast irons and welded assemblies. For other ferrous materials, this document gives guidance. The registration levels and acceptance criteria are to be adapted. In this document, phased array is used both for phased array technique and TFM technique.
This document specifies requirements for phased array ultrasonic examination of steel castings with low ultrasonic attenuation. It is applicable to ferritic, bainitic and martensitic microstructures. It specifies the registration levels and acceptance criteria. This document is applicable to the ultrasonic examination of steel castings with a wall thickness of 600 mm or less. For higher wall thicknesses, special agreements apply regarding the test procedure and recording levels. This document does not apply to austenitic steels and cast irons, lamellar graphite and spheroidal cast irons and welded assemblies. For other ferrous materials, this document gives guidance. The registration levels and acceptance criteria are to be adapted. In this document, phased array is used both for phased array technique and TFM technique.
kSIST FprEN 12680-4:2026 is classified under the following ICS (International Classification for Standards) categories: 77.140.80 - Iron and steel castings. The ICS classification helps identify the subject area and facilitates finding related standards.
kSIST FprEN 12680-4:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN 12680-4:2025
01-julij-2025
Livarstvo - Ultrazvočno preskušanje - 4. del: Ultrazvočno preizkušanje jeklenih
ulitkov s faznim nizom
Founding - Ultrasonic testing - Part 4: Phased array ultrasonic testing of steel castings
Gießereiwesen - Ultraschallprüfung - Teil 4: Phased-Array-Ultraschallprüfung von
Stahlgussteilen
Fonderie — Contrôle par ultrasons — Partie 4 : Contrôle par ultrasons en multiéléments
de pièces moulées en acier
Ta slovenski standard je istoveten z: prEN 12680-4
ICS:
77.140.80 Železni in jekleni ulitki Iron and steel castings
oSIST prEN 12680-4:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
oSIST prEN 12680-4:2025
oSIST prEN 12680-4:2025
DRAFT
EUROPEAN STANDARD
prEN 12680-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2025
ICS 77.140.80
English Version
Founding - Ultrasonic testing - Part 4: Phased array
ultrasonic testing of steel castings
Fonderie - Contrôle par ultrasons - Partie 4: Contrôle Gießereiwesen - Ultraschallprüfung - Teil 4: Phased-
par ultrasons multiéléments de pièces en acier moulé Array-Ultraschallprüfung von Stahlgussteilen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 190.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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
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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12680-4:2025 E
worldwide for CEN national Members.
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Requirements before ordering . 9
4.1 Order information . 9
4.2 Scope of examination. 9
4.3 Test procedure . 9
5 Personnel qualification . 10
6 Equipment . 10
6.1 General. 10
6.2 Ultrasonic instrument . 10
6.3 Probes . 10
6.4 Scanning mechanisms . 10
7 Preparation before testing . 10
7.1 Equipment checking . 10
7.2 Test and scan parameters . 11
7.3 Geometric considerations . 11
7.4 Preparation of scanning surfaces . 12
7.5 Temperature. 12
7.6 Coupling medium . 12
7.7 The suitability of material for phased array ultrasonic examination . 12
8 Time base and sensitivity settings . 13
8.1 Parameters . 13
8.1.1 General. 13
8.1.2 Echo selection gate . 13
8.1.3 Sensitivity setting . 13
8.1.4 Transfer correction . 13
8.2 Parameters checking . 13
8.3 Reference blocks . 14
8.3.1 General. 14
8.3.2 Material . 14
8.3.3 Reference reflectors. 14
9 Test operating mode . 14
9.1 Requirements . 14
9.2 Recommendations . 15
9.3 Data acquisition with position encoder(s) . 15
10 Interpretation and analysis of phased-array network data . 16
10.1 General. 16
10.2 Assessing the quality of phased-array ultrasonic inspection data . 16
10.3 Identification of relevant (or true) indications . 16
10.4 Classification and sizing of relevant indications . 17
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
10.5 Recording of data collected . 17
10.6 Areas of the wall section . 17
10.7 Severity levels . 17
11 Test report . 17
Annex A (informative) Examples of reference blocks . 22
Bibliography . 23
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
European foreword
This document (prEN 12680-4:2025) has been prepared by Technical Committee CEN/TC 190
“Foundry technology”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
EN 12680-4, “Founding — Ultrasonic testing — Part 4: Phased array ultrasonic testing of steel castings
This is one of four European Standards for ultrasonic testing. The other standards are:
— EN 12680-1, Founding — Ultrasonic testing — Part 1: Steel castings for general purposes;
— EN 12680-2, Founding — Ultrasonic testing — Part 2: Steel castings for highly stressed components;
— EN 12680-3, Founding — Ultrasonic testing — Part 3: Spheroidal graphite cast iron castings.
Annex A is informative.
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
1 Scope
This document specifies requirements for phased array ultrasonic examination of steel castings with
low ultrasonic attenuation. It is applicable to ferritic, bainitic and martensitic microstructures. It
specifies the registration levels and acceptance criteria.
This document applies to the ultrasonic examination of steel castings with a wall thickness of 600 mm
or less.
For higher wall thicknesses, special agreements apply regarding the test procedure and recording
levels.
This document does not apply to austenitic steels and cast irons, lamellar graphite and spheroidal cast
irons and welded assemblies. For other ferrous materials, this document gives guidance. The
registration levels and acceptance criteria are to be adapted.
In this document, phased array is used both for phased array technique and TFM technique.
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.
EN 12680-1, Founding — Ultrasonic testing — Part 1: Steel castings for general purposes
EN ISO 5577, Non-destructive testing — Ultrasonic testing — Vocabulary (ISO 5577)
EN ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel (ISO 9712)
EN ISO 16810, Non-destructive testing — Ultrasonic testing — General principles (ISO 16810)
EN ISO 18563-1, Non-destructive testing — Characterization and verification of ultrasonic phased array
equipment — Part 1: Instruments (ISO 18563-1)
EN ISO 18563-2, Non-destructive testing — Characterization and verification of ultrasonic phased array
equipment — Part 2: Array probes (ISO 18563-2)
EN ISO 18563-3, Non-destructive testing — Characterization and verification of ultrasonic phased array
equipment — Part 3: Complete systems (ISO 18563-3)
EN ISO 23243, Non-destructive testing — Ultrasonic testing with arrays — Vocabulary (ISO 23243)
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 5577, EN ISO 23243 and
EN 12680-1 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
3.1
ultrasonic instrument
generic term used for both Phased Array instrument and TFM instrument
3.2
phased array image
one- or two-dimensional display, constructed from the collected information of phased array operation
[SOURCE: EN ISO 23243:2020]
3.3
indication or phased-array indication
pattern or disturbance in the phased array image (3.2) which can need further evaluation
3.4
phased array setup
probe arrangement defined by probe characteristics (e.g. frequency, probe element size, beam angle,
wave mode), probe position (3.5), and the number of probes
[SOURCE: EN ISO 23243:2020]
3.5
probe position
PP
position of the probe reference point relative to the part reference point
Note 1 to entry: The position of the probe reference point depends on the equipment used and shall be known by
the operator to position the indications.
3.6
scan increment
distance between successive data collection points in the direction of scanning (mechanically or
electronically)
[SOURCE: EN ISO 23243:2020]
3.7
active aperture
group of active elements operated together when transmitting and/or receiving
[SOURCE: EN ISO 23243:2020]
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
3.8
electronically covered area
width of the area covered during an electronic scan measured, for example, between the axis of the first
beam and the axis of the last beam of a linear electronic scan
Note 1 to entry: See Figure 1.
3.9
total focusing technic
TFM
synthetic focusing which consists of a reconstruction, inside an ROI (3.10), to focus at many points
which form a grid (3.11), by processing part or all A-scan information of the applicable transmitter-
receiver combinations, taking into account the imaging path (3.12)
[SOURCE: EN ISO 23243:2020]
3.10
region of interest
ROI
two- or three-dimensional region, related to the test volume, for which the image is computed
[SOURCE: EN ISO 23243:2020]
3.11
grid
collection of points in the ROI (3.10) for which the image is calculated and stored, defined by the
position and relative distance between the points in a specified direction
[SOURCE: EN ISO 23243:2020]
3.12
imaging path
path that ultrasonic waves travel from transmitter to image point and from image point to receiver
which is taken into account by the imaging algorithm including refraction(s), reflection(s) and/or mode
conversion(s), if applicable
[SOURCE: EN ISO 23243:2020]
3.13
operating mode
combination of ultrasound beams created by a phased array translator, e.g. fixed angle, E-scan, S-scan,
Total Focusing Method (TFM)
3.14
equivalent discontinuity echo size
smallest indication to be recorded during the evaluation phase of an ultrasound examination, usually
expressed as the equivalent diameter of the side drilled hole
[SOURCE: EN 12680-1, modified — side drilled hole instead of flat bottom hole]
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
Key
1 Array probe
2 Active aperture (grey elements)
3 Moving active aperture of the electronic linear scanning
4 Summed A-scan for a given shot
5 L-scan presentation
6 Electronic scanning resolution
7 Electronically covered area
Figure 1 — Electronically covered area
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
4 Requirements before ordering
4.1 Order information
The following information shall be available at the time of inquiry and order (see also
EN ISO 16810:2024, Clause 5):
a) the areas of the casting and the number or percentage of castings to which phased array ultrasonic
testing requirements apply (examination volume, extent of examination);
b) calibration and reference blocks used;
c) requirements for access, surface conditions and temperature;
d) the stage of manufacture or operation at which testing is to be carried out;
e) if there are additional requirements for the test procedure, see also Clause 7.
4.2 Scope of examination
The casting shall be tested so that the agreed areas are covered (insofar as this is possible from the
shape of the casting) by the use of the best applicable test technique.
For wall thicknesses greater than 600 mm, agreement shall be made between the manufacturer and the
customer on the severity levels, test procedure and the recording of the test results.
4.3 Test procedure
A written test procedure is required.
The procedure includes at least the following information:
a) purpose and scope of testing;
b) operating techniques;
c) severity levels;
d) personnel qualification and training requirements;
e) equipment requirements (including, but not limited to, frequency, sampling frequency, pitch
between elements, element size);
f) reference and/or calibration blocks;
g) equipment settings and checks;
h) accessibility and surface conditions;
i) scan plan;
j) indication evaluation levels;
k) acceptance and/or registration levels;
l) reporting requirements;
m) environmental and safety issues.
oSIST prEN 12680-4:2025
prEN 12680-4:2025 (E)
5 Personnel qualification
Personnel performing non-destructive testing shall be qualified in accordance with this document and
have an appropriate level of qualification in ultrasonic testing in accordance with EN ISO 9712 or an
equivalent standard in the foundry sector.
In addition to general knowledge of ultrasonic inspection of castings, operators shall also be familiar
with and have training and practical experience in the use of the phased array technic and total focusing
technique (TFM).
6 Equipment
6.1 General
Ultrasonic inspection equipment used for phased-array testing shall comply with the requirements of
EN ISO 18563-1, EN ISO 18563-2 and EN ISO 18563-3 where applicable.
6.2 Ultrasonic instrument
The ultrasonic instrument shall be able to manage the probe(s) so as to generate beams adapted to the
geometry of the part, the material structure, and the required severity level.
The ultrasonic instrument shall be able to generate several settings simultaneously, in particular for
monitoring both the background echo and the appearance of a defect echo.
Depending on the application (for example sponge shrinkages), it may be necessary to display the TFM
image at the same time as the electronic scanning in order to ensure the correct positioning of the
region of interest (ROI) and acquire simultaneously electronic scanning and TFM data.
It is recommended to use an A-scan sampling frequency of at least six times the nominal frequency of
the probe.
6.3 Probes
Both longitudinal waves and transverse waves can be used.
The probe shall take into account the surface curvature (e.g. curved wedge, flexible probe …) to
transmit the ultrasonic signal into the part.
The number of dead elements on each active aperture shall be a maximum of 1 in 16 and they shall not
be adjacent. For active aperture using fewer than 16 elements, no dead elements are permitted unless
adequate performance is demonstrated.
6.4 Scanning mechanisms
To ensure consistency of images (collected data), guidance devices and scanning encoders can be used
to communicate the position of the probe relative to an origin point in the part at any time.
7 Preparation before testing
7.1 Equipment checking
The equipment necessary to performed the tests shall be to respect the requirements defined by the
testing specifications. It should be verified that all used channels, probes and cables of the phased array
ultrasound system are functional. To do this, it shall be checked daily using reference blocks provided
for this purpose (see 8.3). If a system component fails, corrective action shall be taken and the system
shall be re-verified according to ISO 18563-3.
...