GB/T 47400-2026 X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 47400-2026
X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints
石油化工用聚乙烯管道焊接接头X射线数字成像检测方法
Issue date: 2026-03-31 Implementation date: 2026-10-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Symbols and Explanations
5 General Requirements
6 Testing Equipment and Materials
7 Testing Method
8 Defect Identification and Measurement
9 Result Description and Determination
10 Testing Records and Reports
Annex A (Normative) Wire Type Image Quality Indicator
Annex B (Normative) Stepped Hole Type Image Quality Indicator
Annex C (Informative) Typical Defect Images
X-ray digital radiography testing method for welded joints of polyethylene pipelines for petrochemical industry
1 Scope
This document provides the symbols and explanations, general requirements, testing equipment and materials, testing method, defect identification and measurement, result description and determination, testing records and reports for X ray digital radiography testing of polyethylene (PE) pipeline welded joints.
This document applies to X ray digital radiography testing of butt fusion joints and electrofusion joints of polyethylene pipelines with a nominal wall thickness of 2 mm to 100 mm.
This document also applies to X ray digital radiography testing of welded joints of other thermoplastic pipelines.
2 Normative References
The following documents are essential for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 3323.2 Non destructive testing of welds — Radiographic testing — Part 2: X and gamma ray techniques with digital detectors
GB/T 12604.2 Non destructive testing — Terminology — Radiographic testing
GB/T 12604.11 Non destructive testing — Terminology — X ray digital radiography testing
GB/T 19278 General terms and definitions for thermoplastic pipes, fittings and valves
GB/T 23901.1 Non destructive testing — Image quality of radiographs — Part 1: Determination of the image quality value using wire type image quality indicators
GB/T 23901.2 Non destructive testing — Image quality of radiographs — Part 2: Determination of the image quality value using step/hole type image quality indicators
GB/T 23901.5 Non destructive testing — Image quality of radiographs — Part 5: Determination of the image unsharpness value using duplex wire type image quality indicators
NB/T 47013.1 Nondestructive testing of pressure equipment — Part 1: General requirements
NB/T 47013.11-2023 Nondestructive testing of pressure equipment — Part 11: X ray digital radiography testing
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 3323.2, GB/T 12604.2, GB/T 12604.11, GB/T 19278 and the following apply.
3.1 butt fusion joint
A connection formed by heating the surfaces to be welded using a special heating device during polyethylene pipeline welding, and then pressing them together to fuse them into one piece.
3.2 electrofusion joint
A connection formed during polyethylene pipeline welding by energising the resistance wire pre embedded on the inner side of the polyethylene electrofusion sleeve. The outer surface of the polyethylene pipe inserted into the electrofusion sleeve and the inner surface of the electrofusion sleeve are sufficiently melted and blended, which upon cooling forms the connection (structural type shown in Figure 1).
3.3 cold welding
A welding quality defect formed during polyethylene pipeline welding due to insufficient heat in the weld fusion zone caused by too low a heating temperature or too short a heating time, resulting in incomplete melting and blending of the polyethylene material.
NOTE: On a positive X ray digital radiography image, a cold welding defect appears as a continuous line located at the fusion zone that is of a higher grey level than the image of the pipe base material. The mechanical properties of the cold welding area are much lower than those of the base material.
3.4 overwelding
A welding quality defect formed during polyethylene pipeline welding due to excessive bead size in the fusion zone of a butt fusion joint caused by too high a heating temperature and/or too long a heating time and/or too high a welding pressure, or due to overflow of melted material during electrofusion welding.
NOTE: On a positive X ray digital radiography image, an overwelding defect in a butt fusion joint appears as an excessively large bead at the fusion zone of the welded joint or as dense holes in the fusion zone. An overwelding defect in an electrofusion joint appears as characteristics such as pipe deformation, material overflow, disordered resistance wires and holes.
3.5 lack of fusion
A welding quality defect formed during polyethylene pipeline welding due to severe deviation in the welding process or excessive gap at the welded joint, resulting in failure of the polymer material in the weld fusion zone to fuse.
NOTE: On a positive X ray digital radiography image, a lack of fusion defect appears as a discontinuous line located at the welding interface that is of a higher grey level than the image of the pipe base material.
3.6 hole
A cavity formed inside a welded joint during polyethylene pipeline welding due to shrinkage cavities, gas bubbles or other reasons.
NOTE: On a positive X ray digital radiography image, a hole defect appears as an irregularly round or pupa shaped image with a higher grey level than the pipe base material, with smooth edges, no sharp corners and a clear outline. Dense holes appear as clustered or grouped distributions.
3.7 inclusion
A defect formed during polyethylene pipeline welding when foreign impurities, such as sediment or plant matter, that have not been cleaned from the welded joint area are incorporated into the fusion surface during welding.
NOTE: On a positive X ray digital radiography image, an inclusion defect appears as a dot like, strip like, flake like or clustered image of a lower grey level than the image of the pipe base material.
3.8 crack
A linear opening in a welded joint of a polyethylene pipeline caused by material shrinkage or stress after cooling.
NOTE: On a positive X ray digital radiography image, a crack defect appears as a linear image of a higher grey level than the image of the pipe base material.
3.9 incomplete insertion of pipe
A defect formed when the welding end of the polyethylene pipe is not inserted into the set position due to excessive dimensional deviation or incorrect installation method during electrofusion welding of the polyethylene pipeline.
NOTE: On a positive X ray digital radiography image, an incomplete insertion defect appears as a regular or irregular annular image of a higher grey level than the image of the pipe base material.
3.10 effective evaluation range
The area over which the quality of the welded joint of the inspected workpiece is evaluated.
4 Symbols and Explanations
The symbols and explanations given in Table 1 apply to this document.
5 General Requirements
5.1 During testing, the testing personnel, testing environmental conditions and radiation safety protection shall comply with the relevant requirements of NB/T 47013.11-2023.
5.2 Personnel engaged in X ray digital radiography non destructive testing of polyethylene pipeline welded joints shall have an understanding of the manufacturing process, welding technology, welding processes and defect characteristics of polyethylene pipelines.
5.3 Before testing, testing procedure documents shall be prepared, including a testing procedure specification and testing operating instructions.
5.4 The preparation and validation of the testing procedure specification and testing operating instructions shall comply with the provisions of NB/T 47013.11-2023.
5.5 Before testing, the appearance of the welded joint shall be inspected. If any foreign matter is present, it shall be cleaned immediately. If the shape of the welded joint affects the testing result, appropriate trimming shall be carried out.
Standard
GB/T 47400-2026 X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints (English Version)
Standard No.
GB/T 47400-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
21500 words
Price(USD)
645.0
Implemented on
2026-10-1
Delivery
via email in 1~8 business day
Detail of GB/T 47400-2026
Standard No.
GB/T 47400-2026
English Name
X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints
GB/T 47400-2026 X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 47400-2026
X-ray digital imaging method for detection of petrochemical polyethylene pipe welded joints
石油化工用聚乙烯管道焊接接头X射线数字成像检测方法
Issue date: 2026-03-31 Implementation date: 2026-10-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Symbols and Explanations
5 General Requirements
6 Testing Equipment and Materials
7 Testing Method
8 Defect Identification and Measurement
9 Result Description and Determination
10 Testing Records and Reports
Annex A (Normative) Wire Type Image Quality Indicator
Annex B (Normative) Stepped Hole Type Image Quality Indicator
Annex C (Informative) Typical Defect Images
X-ray digital radiography testing method for welded joints of polyethylene pipelines for petrochemical industry
1 Scope
This document provides the symbols and explanations, general requirements, testing equipment and materials, testing method, defect identification and measurement, result description and determination, testing records and reports for X ray digital radiography testing of polyethylene (PE) pipeline welded joints.
This document applies to X ray digital radiography testing of butt fusion joints and electrofusion joints of polyethylene pipelines with a nominal wall thickness of 2 mm to 100 mm.
This document also applies to X ray digital radiography testing of welded joints of other thermoplastic pipelines.
2 Normative References
The following documents are essential for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 3323.2 Non destructive testing of welds — Radiographic testing — Part 2: X and gamma ray techniques with digital detectors
GB/T 12604.2 Non destructive testing — Terminology — Radiographic testing
GB/T 12604.11 Non destructive testing — Terminology — X ray digital radiography testing
GB/T 19278 General terms and definitions for thermoplastic pipes, fittings and valves
GB/T 23901.1 Non destructive testing — Image quality of radiographs — Part 1: Determination of the image quality value using wire type image quality indicators
GB/T 23901.2 Non destructive testing — Image quality of radiographs — Part 2: Determination of the image quality value using step/hole type image quality indicators
GB/T 23901.5 Non destructive testing — Image quality of radiographs — Part 5: Determination of the image unsharpness value using duplex wire type image quality indicators
NB/T 47013.1 Nondestructive testing of pressure equipment — Part 1: General requirements
NB/T 47013.11-2023 Nondestructive testing of pressure equipment — Part 11: X ray digital radiography testing
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 3323.2, GB/T 12604.2, GB/T 12604.11, GB/T 19278 and the following apply.
3.1 butt fusion joint
A connection formed by heating the surfaces to be welded using a special heating device during polyethylene pipeline welding, and then pressing them together to fuse them into one piece.
3.2 electrofusion joint
A connection formed during polyethylene pipeline welding by energising the resistance wire pre embedded on the inner side of the polyethylene electrofusion sleeve. The outer surface of the polyethylene pipe inserted into the electrofusion sleeve and the inner surface of the electrofusion sleeve are sufficiently melted and blended, which upon cooling forms the connection (structural type shown in Figure 1).
3.3 cold welding
A welding quality defect formed during polyethylene pipeline welding due to insufficient heat in the weld fusion zone caused by too low a heating temperature or too short a heating time, resulting in incomplete melting and blending of the polyethylene material.
NOTE: On a positive X ray digital radiography image, a cold welding defect appears as a continuous line located at the fusion zone that is of a higher grey level than the image of the pipe base material. The mechanical properties of the cold welding area are much lower than those of the base material.
3.4 overwelding
A welding quality defect formed during polyethylene pipeline welding due to excessive bead size in the fusion zone of a butt fusion joint caused by too high a heating temperature and/or too long a heating time and/or too high a welding pressure, or due to overflow of melted material during electrofusion welding.
NOTE: On a positive X ray digital radiography image, an overwelding defect in a butt fusion joint appears as an excessively large bead at the fusion zone of the welded joint or as dense holes in the fusion zone. An overwelding defect in an electrofusion joint appears as characteristics such as pipe deformation, material overflow, disordered resistance wires and holes.
3.5 lack of fusion
A welding quality defect formed during polyethylene pipeline welding due to severe deviation in the welding process or excessive gap at the welded joint, resulting in failure of the polymer material in the weld fusion zone to fuse.
NOTE: On a positive X ray digital radiography image, a lack of fusion defect appears as a discontinuous line located at the welding interface that is of a higher grey level than the image of the pipe base material.
3.6 hole
A cavity formed inside a welded joint during polyethylene pipeline welding due to shrinkage cavities, gas bubbles or other reasons.
NOTE: On a positive X ray digital radiography image, a hole defect appears as an irregularly round or pupa shaped image with a higher grey level than the pipe base material, with smooth edges, no sharp corners and a clear outline. Dense holes appear as clustered or grouped distributions.
3.7 inclusion
A defect formed during polyethylene pipeline welding when foreign impurities, such as sediment or plant matter, that have not been cleaned from the welded joint area are incorporated into the fusion surface during welding.
NOTE: On a positive X ray digital radiography image, an inclusion defect appears as a dot like, strip like, flake like or clustered image of a lower grey level than the image of the pipe base material.
3.8 crack
A linear opening in a welded joint of a polyethylene pipeline caused by material shrinkage or stress after cooling.
NOTE: On a positive X ray digital radiography image, a crack defect appears as a linear image of a higher grey level than the image of the pipe base material.
3.9 incomplete insertion of pipe
A defect formed when the welding end of the polyethylene pipe is not inserted into the set position due to excessive dimensional deviation or incorrect installation method during electrofusion welding of the polyethylene pipeline.
NOTE: On a positive X ray digital radiography image, an incomplete insertion defect appears as a regular or irregular annular image of a higher grey level than the image of the pipe base material.
3.10 effective evaluation range
The area over which the quality of the welded joint of the inspected workpiece is evaluated.
4 Symbols and Explanations
The symbols and explanations given in Table 1 apply to this document.
5 General Requirements
5.1 During testing, the testing personnel, testing environmental conditions and radiation safety protection shall comply with the relevant requirements of NB/T 47013.11-2023.
5.2 Personnel engaged in X ray digital radiography non destructive testing of polyethylene pipeline welded joints shall have an understanding of the manufacturing process, welding technology, welding processes and defect characteristics of polyethylene pipelines.
5.3 Before testing, testing procedure documents shall be prepared, including a testing procedure specification and testing operating instructions.
5.4 The preparation and validation of the testing procedure specification and testing operating instructions shall comply with the provisions of NB/T 47013.11-2023.
5.5 Before testing, the appearance of the welded joint shall be inspected. If any foreign matter is present, it shall be cleaned immediately. If the shape of the welded joint affects the testing result, appropriate trimming shall be carried out.
