🔩 Detection of laminar imperfections (imperfections in the wall, approximately parallel to the tube surface) in seamless and welded steel tubes (except submerged arc-welded SAW tubes) — automated ultrasonic pulse-echo testing with the beam normal to the surface, frequency 2–10 MHz, transducers (or phased array apertures) preferably up to 25 mm, over the full periphery, in the area adjacent to the weld or at the tube ends; suspect tubes are sized manually according to Annex A, PN-EN ISO 10893-8

Materials and NDT PN-EN ISO 10893-8

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-EN ISO 10893-8:2011, in full (our translation of the Polish card text): “Requirements are specified for automated ultrasonic detection of laminar imperfections in seamless and welded steel tubes, excluding submerged arc-welded (SAW) tubes, in the areas adjacent to the weld seam in welded tubes and at the ends of seamless and welded tubes. General requirements, the test method, calibration and checking and the test report are specified”. Scope from the card of amendment PN-EN ISO 10893-8:2011/A1:2020-12: “Change of acceptance criteria”. We read the text of the standard in the preview of ISO 10893-8:2011 from the cover to the beginning of clause 5.2 (full peripheral testing — up to the sentence referring to Table 1, page 3); we do not have Table 1, the rest of Clause 5, Clauses 6–9 (reference tube and dimensions of reference standards, calibration and checking, acceptance and procedure for suspect tubes, test report) or the normative Annex A (manual sizing of laminations). The preview of amendment ISO 10893-8:2011/Amd 1:2020 contains the whole amendment (one page after the foreword): in clause 8.1.2 the second sentence “If after two consecutive retests all signals are lower than the trigger/alarm level, the tube shall be deemed to have passed this test otherwise the tube shall be designated as suspect” was replaced by the sentence “If after one retest all signals are lower than the trigger/alarm level, the tube shall be deemed to have passed this test otherwise the tube shall be designated as suspect” — the tube is deemed acceptable when, after one retest, all signals are below the trigger/alarm level, otherwise it is designated as suspect; we do not have the first sentence of clause 8.1.2.

ACCORDING TO THE TEXT OF ISO 10893-8:2011 (foreword, Clauses 1–5.2). The standard was prepared by ISO/TC 17/SC 19 (technical delivery conditions for steel tubes for pressure purposes). The first edition replaced ISO 10124:1994, ISO 11496:1993 and ISO 13663:1995. The ISO 10893 series (non-destructive testing of steel tubes) has 12 parts — among others Part 9: detection of laminar imperfections in strip/plate for the manufacture of welded tubes, Part 10: full peripheral ultrasonic testing for longitudinal and transverse imperfections, Part 11: ultrasonic testing of the weld seam, Part 12: thickness testing. Scope (Clause 1): requirements for automated ultrasonic testing for the detection of laminar imperfections a) in the pipe body (full peripheral testing) of seamless and welded tubes, except submerged arc-welded (SAW), or b) in the area adjacent to the weld seam of welded tubes, and optionally c) at the ends of seamless and welded tubes (full periphery); the standard can also be applicable to testing of circular hollow sections; note: for welded tubes an alternative method is detection of laminar imperfections in strip/plate prior to forming (ISO 10893-9). Normative references: ISO 5577 (UT vocabulary), ISO 9712 (personnel qualification), ISO 10893-6 and ISO 10893-7 (radiography of the weld seam), ISO 11484 (employer’s qualification system for NDT personnel). Definitions (Clause 3): reference standard — for calibration of equipment (e.g. drilled holes, notches, recesses); reference tube — a tube or length of tube containing reference standards (also covers the reference sample: segment of tube, plate or strip); laminar imperfection — an imperfection within the wall thickness, generally parallel to the tube surface, whose extension can be calculated from its outlined area on the external surface; seamless and welded tube; manufacturer; agreement — arrangement between manufacturer and purchaser at enquiry and order. General requirements (Clause 4): testing after completion of all primary production operations (rolling, heat treatment, cold and hot working, sizing, straightening), unless otherwise specified by the product standard or agreed; tubes sufficiently straight, surfaces sufficiently free of foreign matter; testing by trained operators qualified according to ISO 9712, ISO 11484 or equivalent, supervised by competent personnel nominated by the manufacturer; third-party inspection — by agreement; operating authorization according to a written procedure, NDT operations approved by a level 3 individual approved by the employer. Method (5.1): according to the product standard — pulse-echo technique according to 5.2 or 5.3 and/or 5.4, ultrasound transmitted normal to the tube surface; in testing according to 5.2 or 5.3 the relative speed must not vary by more than ± 10 %; in determining the extent of a suspect area, adjacent areas separated by less than the smaller of the minor axes of two laminations are considered as one lamination; short lengths at both ends may remain untested — they are dealt with according to the product standard (see 5.4); test frequency from 2 MHz to 10 MHz; suggested maximum width of a transducer (or active aperture of a phased array probe) — 25 mm in any direction, larger transducers are permitted if they detect the adopted reference standard (on request this must be demonstrated); the equipment must classify tubes as acceptable or suspect by an automated trigger/alarm level combined with marking and/or sorting; manual testing — according to Annex A; note: for wall thicknesses below 5 mm, where detection and sizing of laminations by this method can be difficult, the manufacturer and purchaser may agree on another method. Full peripheral testing (5.2): the tube and the transducer assembly are moved relative to each other so as to scan the surface and detect laminations of a size equal to or greater than the minimum lamination size Bmin, with the circumferential dimension Cmin calculated according to Table 1 — this is where the part we read ends.

STATUS (cards as of 02.10.2026). The card of PN-EN ISO 10893-8:2011 in the English version (published 21-07-2011, 13 pages, price group G) does not carry the heading “Wycofana” (withdrawn): Metallurgy Sector, KT 123 Testing of Metal Properties, ICS 77.140.75, 23.040.10, 77.040.20, “Introduces: EN ISO 10893-8:2011 [IDT], ISO 10893-8:2011 [IDT]”, “Replaces: PN-EN 10246-14:2001, PN-EN 10246-16:2002, PN-EN 10246-17:2002 – Polish versions”, “Additional elements: PN-EN ISO 10893-8:2011/A1:2020-12E”. The card of amendment PN-EN ISO 10893-8:2011/A1:2020-12 in the English version (published 07-12-2020, 12 pages) does not carry the heading “Wycofana”, “Introduces: EN ISO 10893-8:2011/A1:2020 [IDT], ISO 10893-8:2011/Amd 1:2020 [IDT]”. The PKN search for “PN-EN ISO 10893-8” (02.10.2026) shows only these two items.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, load up to 17.09.2026, read on 02.10.2026). The number 10893-8 appears in 8 records at 8 laboratories: AB 313, AB 608, AB 1425, AB 1623, AB 1827, AB 1898, AB 1900, AB 1919. In the current scopes on the PCA website (read on 02.10.2026, issues from 27.12.2024 to 25.08.2026): “PN-EN ISO 10893-8:2011” without the amendment — AB 313, AB 1425; with the amendment added “PN-EN ISO 10893-8:2011/A1:2020-12” — AB 1623, AB 1827, AB 1898; restricted to Annex A (manual sizing) — AB 608 (“Annex A”, without a year), AB 1827 (“Anex A”), AB 1900 (“Annex A”), AB 1919 (“Załącznik A”). No row is set in bold italics. The “Laboratories” tab searches for entries STARTING WITH “PN-EN ISO 10893-8” and shows all 8 laboratories and 8 items — checked with the tab query on the labcoda.pl production server on 02.10.2026.

WHAT THE LABORATORIES TEST (items in the PCA scopes). Steel tubes, seamless and welded tubes, steel tubular products — “internal discontinuities, ultrasonic method” (most), “laminations, ultrasonic method” (AB 1623). Alongside PN-EN ISO 10893-9 (laminations in strip and plate; AB 1425, AB 1623, AB 1827), PN-EN ISO 10893-11 (AB 1623, AB 1827, AB 1898), PN-EN ISO 10893-10 (AB 1827, AB 1898); at seven of the eight also PN-EN 10160 (flat products), at six thickness measurement PN-EN ISO 16809.

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. Scope: the Annex A test is manual sizing of laminations in suspect tubes, not automated testing of the whole tube — a laboratory accredited only for Annex A does not perform testing according to 5.2–5.4. Criteria: according to the 2011 edition without the amendment, a tube passes the retest only after two consecutive retests with signals below the threshold, according to amendment A1:2020 — after one; citing the 2011 edition alone (e.g. AB 313, AB 1425) refers to the first rule. Speed: a change in relative speed of more than ± 10 % spoils surface coverage. Assessment: adjacent suspect areas closer together than the smaller of the minor axes of the laminations count as one lamination — separating them underestimates the extent. Ends: untested end lengths must be covered by testing according to 5.4 or the product standard. Thin walls: below 5 mm, detection and sizing can be difficult — it is worth agreeing on another method. SAW tubes: full peripheral testing according to 5.2 does not cover them. Equipment: a transducer wider than 25 mm requires demonstration of detectability of the reference standard.

WHAT WE DO NOT GIVE. We do not have Table 1 (Bmin and Cmin), the rest of clause 5.2 or clauses 5.3–5.4, Clause 6 (reference tube, dimensions and verification of reference standards), Clause 7 (calibration and checking of equipment), Clause 8 (acceptance, procedure for suspect tubes), Clause 9 (test report) or Annex A — so we do not give the smallest detectable laminations, reference standards or acceptance criteria apart from the sentence of clause 8.1.2 changed by A1:2020.

Method principle

Ultrasound is introduced normal to the tube surface by the pulse-echo technique (2–10 MHz); the tube and the transducer assembly are moved relative to each other at constant speed (± 10 %), scanning the full periphery, the area adjacent to the weld or the tube ends; an echo from an imperfection parallel to the surface exceeding the automatic alarm level marks the tube as suspect, and the extent of the lamination is then established manually according to Annex A.

Applications

• Seamless and welded steel tubes (except SAW), including for pressure purposes — laminar imperfections in the wall, 8 laboratories
• The area adjacent to the weld seam of welded tubes and the tube ends
• Manual sizing of laminations in suspect tubes (Annex A); circular hollow sections

Key parameters

Standard

Standard number

PN-EN ISO 10893-8:2011 (wersja angielska; EN ISO 10893-8:2011 IDT, ISO 10893-8:2011 IDT) ze zmianą PN-EN ISO 10893-8:2011/A1:2020-12 (ISO 10893-8:2011/Amd 1:2020)

Title (PL)

Badania nieniszczące rur stalowych — Część 8: Automatyczne badanie ultradźwiękowe rur stalowych bez szwu i spawanych w celu wykrycia rozwarstwień

Title (EN)

Non-destructive testing of steel tubes — Part 8: Automated ultrasonic testing of seamless and welded steel tubes for the detection of laminar imperfections

Step-by-step procedure

1. Preparation of tubes

   Testing after completion of primary production operations; tubes straight, surfaces free of foreign matter; personnel according to ISO 9712 or ISO 11484. PN-EN ISO 10893-8:2011 with A1:2020-12 current (cards as of 02.10.2026).

2. Calibration

   Setting up the equipment on a reference tube with reference standards (Clauses 6–7, details NOT GIVEN); 2–10 MHz, beam normal.

3. Automated testing

   Movement of tube and transducers at constant speed (± 10 %): full periphery (5.2), area adjacent to the weld (5.3) and/or ends (5.4); automatic marking of suspect tubes.

4. Suspect tubes

   Manual sizing of laminations according to Annex A; adjacent areas closer than the smaller of the minor axes — one lamination.

5. Acceptance and report

   Assessment according to the criteria of Clause 8 (NOT GIVEN); clause 8.1.2 as worded by A1:2020 — the tube is acceptable when, after one retest, all signals are below the threshold; test report (Clause 9).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Automated lines with moving tubes — machine movement zones fenced off, work according to plant instructions; the part of the standard we read contains no safety warnings
• SUBSTANTIVE NOTE: accreditation only for Annex A covers manual sizing, not automated testing of tubes; amendment A1:2020 in clause 8.1.2 requires one retest with signals below the threshold instead of two consecutive ones — a reference without A1 refers to the 2011 rule

Frequently asked questions