🔩 Ultrasonic testing of steel castings with ferritic structure for general purposes — detection and evaluation of internal discontinuities by the pulse-echo technique in walls up to 600 mm, according to severity levels agreed for the rim zone and the core zone, PN-EN 12680-1

Materials and NDT PN-EN 12680-1

Overview

WHAT THE STANDARD COVERS. Scope from the PKN card of the 2026-04 edition, in full (our translation): "This document specifies the requirements for the ultrasonic testing of steel castings (with ferritic structure) for general purposes and the methods for determining internal discontinuities by the pulse-echo technique. This document is applicable to the ultrasonic testing of steel castings with wall thicknesses up to and including 600 mm — usually after a heat treatment intended to obtain a fine-grained structure. For greater wall thicknesses, additional agreements apply with respect to the test procedure and recording levels. This document does not apply to austenitic steels and joint welds. For highly stressed components EN 12680-2 applies." We have iTeh samples of both editions: EN 12680-1:2025 (from the cover to Formula (2) in 5.2) and EN 12680-1:2003 (up to 5.3.1).

ACCORDING TO THE 2025 EDITION (foreword, table of contents, Clauses 1–5.2). EN 12680-1:2025 was prepared by working group CEN/TC 190/WG 10 "Testing for inner discontinuities" of committee CEN/TC 190 "Foundry technology" (secretariat DIN); CEN approved it on 22 September 2025; it replaced EN 12680-1:2003, and the list of significant changes is given in Annex C, Table C.1 (outside the sample). It is one of four standards: part 2 — steel castings for highly stressed components, part 3 — spheroidal graphite cast iron castings, part 4 — phased array ultrasonic testing of steel castings. Normative references: EN ISO 16810 (general principles), EN ISO 16811 (sensitivity and range setting), EN ISO 16827 (characterization and sizing of discontinuities), EN ISO 2400 and EN ISO 7963 (calibration blocks No. 1 and No. 2), EN ISO 22232-1, -2 and -3 (instrument, probes, combined equipment), EN ISO 5577 (vocabulary). Definitions: point-like discontinuity — dimensions not larger than the sound-beam width (3.1), extended — larger (3.2); planar — two measurable dimensions (3.3), volumetric — three (3.4); rim zone — 1/3 of the wall thickness from the surface, at most 30 mm (3.5); special rim zone — outer zone with special requirements, e.g. machined surfaces, higher stresses, sealing surfaces (3.6); non-measurable dimension — smaller than the beam width, depending on the probe size and the frequency, in current practice below 3 mm (3.7); finishing welding (3.8); severity level — upper size limit for acceptable discontinuities, depending on the wall-thickness zone (3.9). Requirements: the purchaser specifies the areas and the number or percentage of castings to be tested, the severity levels for the zones, the requirement for a written procedure and any additional requirements (4.1); for walls thicker than 600 mm the severity levels, the procedure and the recording of the results are agreed between the manufacturer and the customer (4.2). The wall is divided into a core zone and rim zones according to the dimensions of the casting ready for assembly; if the foundry does not know the final condition, the result applies to the "as delivered" condition — a discontinuity acceptable in the core of the raw casting may, after machining by the customer, end up in the rim zone and become unacceptable; a discontinuity extending into both zones is evaluated as in the rim zone (4.3). Planar discontinuities (4.4.1): in severity level 1 discontinuities larger than a 3 mm flat-bottomed hole (FBH) are not acceptable; the dimension in the through-wall direction must not exceed 10 % of the thickness, and for a length of up to 10 mm — 25 % of the thickness or 20 mm; a distance of 10 mm decides whether discontinuities are evaluated as one; a discontinuity longer than 3 mm with a non-measurable dimension in depth is taken as 3 mm wide — area A = 3L. The limits for volumetric discontinuities are in Table 1 (outside the sample). When radiographic testing supplements the ultrasonic testing and a discontinuity indicated by radiography lies in the core zone, it is acceptable at one level less severe, e.g. severity level 3 instead of 2 for radiography (4.4.3, EN 1559-2). Personnel — qualification e.g. according to EN ISO 9712 (4.5). Severity level 1 is applied only to weld preparations and special rim zones; for finishing welds — the requirements of the parent metal, unless otherwise agreed (4.6). Testing: principles of EN ISO 16810, 16811 and 16827 (5.1); the suitability of the material is assessed by comparing the height of the reference echo (usually the first back-wall echo) with the noise level on representative areas with parallel surfaces — the reference echo according to Table 2 must be at least 6 dB above the noise; if it is not, the testing has reduced performance, the next larger flat-bottomed hole or side-drilled hole (SDH) diameter detectable with a signal-to-noise ratio of at least 6 dB is stated in the report, and the further procedure is agreed between the manufacturer and the purchaser; Formula (2) converts an FBH diameter into an equivalent SDH diameter (5.2).

ACCORDING TO THE 2003 EDITION (this edition is introduced by PN-EN 12680-1:2005; comparison of the samples of both editions up to 5.2). The 2003 edition was one of three parts (without part 4) and referred to EN 583-1, -2 and -5, EN 12223, EN 27963 and EN 12668-1 to -3 — replaced in 2025 by the EN ISO standards listed above. In severity level 1 indications of planar discontinuities with measurable dimensions were not permissible — the 2025 edition sets this limit by a 3 mm FBH. The 2003 edition recommended confirming the qualification of personnel by certification according to EN 473; the 2025 edition points to EN ISO 9712 or other equivalent recognized standards. The 2025 edition added a reference to part 2 to the scope, defined the rim zone, the non-measurable dimension and the severity level, and in 4.3 — the "as delivered" condition and the evaluation of discontinuities extending into both zones; it calls the former complex discontinuity "extended". The limits of 10 %, 25 % or 20 mm, the distance of 10 mm, the area A = 3L, the one level less severe with radiography and the 6 dB threshold in the assessment of the suitability of the material are in both editions.

STATUS (state of the cards on 30 September 2026). The card of PN-EN 12680-1:2026-04 (English version) has no "Withdrawn" header — this edition is CURRENT: published 27-04-2026, 37 pages, price group R, Metallurgy Sector, KT 301 for Foundry, ICS 77.140.80 and 77.040.20, "Introduces: EN 12680-1:2025 [IDT]", "Replaces: PN-EN 12680-1:2005 - Polish version". The card of PN-EN 12680-1:2005 (Polish version): "Withdrawn and replaced by PN-EN 12680-1:2026-04", published 22-07-2005, withdrawn 27-04-2026, 35 pages, introduces EN 12680-1:2003 [IDT], replaces PN-EN 12680-1:2003 (English version). PKN search for "PN-EN 12680-1" (30 September 2026): the 2026-04 edition only in the English version, without a label; 2005 (PL) and 2003 (EN) — "Withdrawn and replaced by…". Under the same search term the search also shows PN-EN ISO 12680-1 — a different standard: Young's modulus of refractory products by impulse excitation of vibration.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation-scope database, data loaded up to 17 September 2026, read on 30 September 2026). 10 records at 10 laboratories — the same number of cells in the current PCA documents. The notation "PN-EN 12680-1:2005" — 7 laboratories (AB 197, AB 313, AB 1336, AB 1425, AB 1505, AB 1827, AB 1898), "PN-EN 12680-1:2026-04" — AB 1978 (scope issue No. 1 of 26.08.2026), without a year — AB 608 and AB 904, both entries in a flexible scope of accreditation (mark E; flexibility according to the PCA document DA-10). The "Laboratories" tab looks for notations that BEGIN with "PN-EN 12680-1" and will show all 10 laboratories — checked with the tab's query on the production server labcoda.pl on 30 September 2026: 10. Current scopes on the PCA website (read on 30 September 2026, issues from 23.04.2025 to 02.09.2026): the entries with this standard are not suspended (AB 197 has another part of its scope suspended at its own request). The copy splits the AB 313 entry into two records — "Odlewy staliwne o grubości do" (steel castings with a thickness up to) with PN-EN 12680-1:2005 and "600 mm" with PN-EN 12680-2:2005; in the PCA document it is one cell: steel castings with a thickness up to 600 mm, both parts of the standard.

QUANTITY, ITEMS AND RANGE. Internal discontinuities — 6 laboratories (AB 197, AB 608, AB 1336, AB 1425, AB 1505, AB 1827), discontinuities — 4 (AB 313, AB 904, AB 1898, AB 1978); the technique in all ten — ultrasonic method. Items: steel castings — 5 laboratories (AB 608, AB 904, AB 1425, AB 1505, AB 1898), steel castings with a thickness up to 600 mm — AB 313, castings — AB 1827 and AB 1978, steel and iron castings — AB 1336, castings and products of cast iron, cast steel and non-ferrous metal alloys — AB 197; the last two entries cover items wider than part 1 (only steel with ferritic structure) and give parts 2 and 3 alongside. The entries give no numerical ranges — apart from the thickness of 600 mm at AB 313, equal to the limit of the standard.

ALONGSIDE THIS STANDARD. In the same PCA cell: part 2 (steel castings for highly stressed components) — 7 laboratories (AB 197, AB 313, AB 608, AB 904, AB 1336, AB 1827, AB 1978), part 3 (spheroidal graphite cast iron castings) — 4 (AB 197, AB 1336, AB 1827, AB 1978); AB 608 assigns part 3 to a separate item — spheroidal graphite cast iron castings (a separate record in the copy). Only AB 1978 gives all three parts in the 2026-04 edition; the others — parts 2 and 3 in the 2005 and 2012 editions or without a year. PN-EN ISO 16810 (general principles) stands in the same cell at 3 laboratories: AB 904 (without a year, together with PN-EN ISO 16811 and 16827), AB 1827 (2025-04) and AB 1898 (2014-06 and 2025-04). The copy has 12 records at 11 laboratories with castings as the item and an ultrasonic method: apart from the 10 records of this standard these are spheroidal graphite cast iron castings at AB 608 (part 3) and the UCI hardness measurement of large metallurgical and foundry products at AB 099 (ASTM A1038) — the copy has no record with steel castings tested ultrasonically without this standard. The general principles of ultrasonic testing (PN-EN ISO 16810), ultrasonic testing of forgings (PN-EN 10228-3) and the qualification of NDT personnel (PN-EN ISO 9712) have separate entries in the Knowledge Base.

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — edition: seven of the ten laboratories cite PN-EN 12680-1:2005, withdrawn on 27-04-2026; the criterion of severity level 1 for planar discontinuities has changed (indications with measurable dimensions in 2003, a 3 mm FBH in 2025) — the limits are read from the edition cited in the order. Second — condition of the casting: the zones refer to the dimensions of the casting ready for assembly; the result of testing a raw casting applies to the "as delivered" condition, and a discontinuity acceptable in the core may end up in the rim zone after machining. Third — suitability of the material: if the reference echo is not at least 6 dB above the noise, "no indications" does not mean "no discontinuities" — the report must give the smallest detectable reflector (FBH or SDH). Fourth — items: the standard concerns steel with ferritic structure with walls up to 600 mm; it does not cover austenitic steels, joint welds or highly stressed components (part 2), and spheroidal graphite cast iron has part 3. Fifth — severity levels: acceptability depends on the level assigned to the zone; a result without the level and the zone does not say whether the casting meets the requirements, and severity level 1 is applied only to weld preparations and special rim zones. Sixth — number: PN-EN ISO 12680-1 is a different standard (refractory products); the copy has no records of it.

WHAT WE DO NOT GIVE. The samples end at 5.2 (2025 edition) and 5.3.1 (2003 edition): we do not give the limits from the figure for planar discontinuities or from Table 1 for volumetric ones, the reflector diameters from Table 2, the full form of Formula (2), the requirements for the instrument, the probes and the coupling medium (the requirements for the instrument we see only in the withdrawn 2003 edition), the range and sensitivity setting, the recording levels, the requirements for the report or the list of changes in Annex C.

Method principle

A steel casting is tested by the pulse-echo technique according to the principles of EN ISO 16810, 16811 and 16827: first the suitability of the material is assessed (reference echo at least 6 dB above the noise), then internal discontinuities are detected, characterized and sized. The wall is divided into a rim zone (1/3 of the thickness, at most 30 mm) and a core zone, and planar and volumetric discontinuities are evaluated separately according to the severity levels agreed for the zones. The values of the limits, reflector diameters and recording levels are NOT GIVEN.

Applications

• Steel castings with ferritic structure for general purposes, with walls up to 600 mm — in the scopes of 10 laboratories
• Acceptance of castings according to the severity levels agreed in the order for the zones (parent metal, weld preparations, special rim zones)
• In the scopes together with part 2 (highly stressed components — 7 laboratories) and part 3 (spheroidal graphite cast iron — 4 in the same cell, AB 608 separately)

Key parameters

Standard

Standard number

PN-EN 12680-1:2026-04 (wersja angielska; EN 12680-1:2025 IDT)

Title (PL)

Odlewnictwo — Badania ultradźwiękowe — Część 1: Odlewy staliwne ogólnego stosowania

Title (EN)

Founding — Ultrasonic testing — Part 1: Steel castings for general purposes

Step-by-step procedure

1. Order

   Areas and number or percentage of castings, severity levels for the zones, written procedure, additional requirements (4.1). PN-EN 12680-1:2026-04 current; 2005 edition withdrawn 27-04-2026 (state of the cards on 30 September 2026).

2. Zones and surface

   Division of the wall into a rim zone and a core zone according to the dimensions after machining (4.3); surface preparation — 5.4, NOT GIVEN.

3. Suitability of the material

   Reference echo (usually the first back-wall echo) at least 6 dB above the noise on representative areas with parallel surfaces (5.2).

4. Testing

   Pulse-echo technique according to EN ISO 16810, 16811 and 16827: range and sensitivity, recording, characterization and sizing of discontinuities (5.5 — NOT GIVEN).

5. Evaluation and report

   Comparison with the limits of the severity level for planar (figure) and volumetric (Table 1) discontinuities; report — 5.6.

Required equipment and apparatus

Health and safety (OHS)

• The testing is performed by qualified personnel, e.g. according to EN ISO 9712 (4.5); the samples of the standard contain no health and safety warning
• SUBSTANTIVE NOTE: the acceptance criteria depend on the edition (2003 or 2025) and on the severity level assigned to the zone — a result without them does not decide on the fitness of the casting

Frequently asked questions