GB/T 42662-2023Non-destructive testing of steel tubes - Automated ultrasonic testing for the detection of laminar imperfections in strip/plate used for the manufacture of welded steel tubes (English PDF)

Foreword

This document was issued on 6 August 2023 by the State Administration for Market Regulation; Standardization Administration of the PRC and takes effect on 1 March 2024.

It is a GB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

1 Scope

GB/T 42662-2023 covers the automated ultrasonic examination of steel strip and plate for laminar imperfections, carried out before or during the forming of welded tube — the general requirements, which put the examination ahead of or inside tube making and demand a smooth surface free of anything that would break the coupling; the testing methods and the coverage they achieve; the reference sample against which sensitivity is set; the calibration and verification of the equipment, statically before each inspection cycle and against the reference imperfections; the acceptance, where strip below the trigger or alarm threshold passes and anything at or above it is handled as the standard directs; and the testing report. Annex A is normative and gives the procedure for sizing an indication by hand-held ultrasound. A lamination is a flat separation lying in the plane of rolling; it survives forming, then opens at the strip edge that becomes the weld bevel or shows up later as hydrogen-induced cracking in sour service, and by then the tube is welded, coated and often in the ground. Written for tube mills, plate suppliers, NDT contractors and pipeline purchasers writing inspection clauses.

This document specifies the requirements for automatic ultrasonic detection of laminar

imperfection in steel strips/plates used for the manufacture of welded steel tubes before

or during the tube making process.

NOTE 1: For welded steel tubes, at the option of the manufacturer, automated ultrasonic testing of

the steel tube for laminar imperfection according to ISO 10893-8 after welding is an alternative

method.

NOTE 2: Upon agreement between the manufacturer and the purchaser, this document is also

applicable to the inspection of steel strips/plates after welding of submerged arc welded steel tubes.

This document also applies to the inspection of steel strips/plates used in the

manufacture of circular hollow steel profiles.

2 Normative references

The following referenced documents are indispensable for the application of this

document. For dated references, only the edition cited applies. For undated references,

the latest edition of the referenced document (including any amendments) applies.

GB/T 9445, Non-destructive testing -- Qualification and certification of NDT

personnel (GB/T 9445-2015, ISO 9712:2012, IDT)

GB/T 12604.1, Non-destructive testing -- Terminology -- Ultrasonic testing (GB/T

12604.1-2020, ISO 5577:2017, MOD)

ISO 11484, Steel products -- Employer’s qualification system for non-destructive

testing (NDT) personnel

3 Terms and definitions

The terms and definitions defined in GB/T 12604.1 and ISO 11484 as well as the

following apply to this document.

3.1 reference standard

Artificial imperfections used to calibrate non-destructive testing equipment.

3.2 reference sample

Samples for calibration.

3.3 tube

A long hollow product with open ends and a cross-section of any shape.

3.4 manufacturer

An organization that produces products in accordance with relevant standards and

declares that the delivered products comply with relevant standards.

3.5 agreement

The contract entered into between the manufacturer and the purchaser at the time of

inquiry and order.

3.6 laminar imperfection

An imperfection in the tube wall that is usually parallel to the surface of the steel tube.

NOTE: Its range can be calculated by measuring the contour area on the outer surface.

4 General requirements

4.1 Ultrasonic testing of straight steel strips/plates shall be carried out before or during

the production of steel tubes.

4.2 The surface of the steel strip/plate to be inspected shall be smooth and free of foreign

matter that would affect the validity of the test results.

4.3 Testing shall be carried out by operators trained in accordance with GB/T 9445, ISO

11484 or equivalent standards, under the supervision of qualified personnel authorized

by the manufacturer. In the case of third-party testing, this shall be negotiated between

the supplier and the purchaser.

Employers shall issue operation authorization certificates in accordance with

procedural documents. NDT operations shall be authorized by NDT Level 3 personnel

approved by the employer.

NOTE: The definitions of Level 1, Level 2, and Level 3 can be found in the corresponding standards,

such as GB/T 9445 and ISO 11484.

6.3 Verification of reference standard

Appropriate techniques shall be used to verify the size and shape of reference standard.