GB/T 46608-2025Non-destructive testing of steel tubes - General rules for the machine vision inspection method for surface defects (English PDF)

Foreword

This document conforms to GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting is scheduled. Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents. This document was proposed by the China Iron and Steel Association. This document is under the jurisdiction of the National Steel Standardization Technical Committee (SAC/TC 183). This document was drafted by: Steel Research Institute NACK Testing Technology Co., Ltd., Beijing University of Science and Technology, Hengyang Valin Steel Pipe Co., Ltd., and Zhejiang... Jinzhou Pipeline Industry Co., Ltd., China National Petroleum Corporation Bohai Petroleum Equipment Manufacturing Co., Ltd., Nanjing Julong Steel Pipe Co., Ltd., Zhejiang Zhongda New Materials Co., Ltd., Daye Special Steel Co., Ltd., Handan Zhengda Steel Pipe Group Co., Ltd., Wuxi Beilai Steel Pipe Co., Ltd. Jiangsu Changbao Plasen Steel Pipe Co., Ltd., Wuhan Zhongke Innovation Technology Co., Ltd., Zhejiang Dewei Stainless Steel Pipe Industry Co., Ltd. Jiangsu Yinhuan Precision Steel Pipe Co., Ltd., Cangxin Nondestructive Testing Equipment Suzhou Co., Ltd., Jiangsu Jinyu Intelligent Testing System Co., Ltd., Jiangsu Hebei Provincial Institute of Product Quality Supervision and Inspection, Hebei Jin'ao Precision Manufacturing Co., Ltd., Jiaxing Yongli Precision Steel Pipe Co., Ltd., Hebei Yingyan Intelligent Technology Co., Ltd., Metallurgical Industry Information Standards Research Institute. The main drafters of this document are. Zhang Jianwei, Xu Ke, Zhu Lin, Wang Zunsheng, Sun Shaoqing, Lü Chengxiu, Gu Jisong, Ding Hui, Zhang Hongshun, and Zhi Xiangdong. Wang Yunyun, Wang Zhimin, Shen Chenxia, Zhuang Zhuojun, Zhang Ying, Qian Jiang, Jia Xin, Zhang Jun, Gu Haizhong, Yuan Kun, Li Siyuan, Zhou Dongdong, Zhang Li, Lei Tao Li Rujiang, Cao Huayong, Dong Hao, Wang Zhi, Kuang Xuejun, Zhu Xiaodong, Li Xiongxiong, Yao Wei, Wu Zhimin, Zhang Qianyi, Yao Jidong, Cheng Jinyong, Gu Zhufeng Liu Guanglei, Fang Huajun, Li Jianyi, Lu Guangping, Wang Weibao, Guo Yong, Chen Binghua, Xing Yaoqi, Li Ting, Wang Xiaowen, Zhang Guangxin, Wang Hongliang, Zhu Guoqing Zhang Hailong, Xue Jianzhong, and Guo Bicheng. Non-destructive testing of steel pipes. surface defects - machine vision inspection Technical Principles

1 Scope

GB/T 46608-2025 is the Chinese national standard covering inspecting tube surfaces with cameras instead of eyes - the lighting and optics that make a lap or a seam visible on a moving tube, the resolution and the detection thresholds, the calibration on reference defects, and the sorting decision. First edition, under the China Iron and Steel Association, in force from 1 May 2026. Issued on 31 October 2025, it has been in force since 1 May 2026.

This document specifies the general requirements, comparison samples, inspection system, system performance requirements, and inspection procedures for machine vision inspection of surface defects in steel pipes. Procedures, result determination, test records and reports. This document applies to the automated visual inspection of defects on the outer surface of steel pipes. Visual inspection of defects on the inner surface of steel pipes shall be performed in accordance with this document.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are listed below. For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document.

GB/T 40659 General Requirements for Online Inspection Systems Based on Machine Vision in Intelligent Manufacturing YB/T 145 Method for Measuring the Size of Artificial Defects in Comparative Specimens for Flaw Detection of Steel Pipes

3 Terms and Definitions

The terms and definitions defined in GB/T 40659 and the following terms and definitions apply to this document.

3.1 Machine visual inspection Machine vision converts the captured information about the steel pipe surface into image signals, which are then transmitted to a dedicated image processing system for analysis based on pixels. Information such as brightness and color is converted into digital signals. The image system performs various operations on these signals to extract the target's features. A detection method that uses target features to determine whether there are defects on the outer surface of the steel pipe being tested.

Note. The detection is carried out using two-dimensional and/or three-dimensional detection methods.

3.2 Data Acquisition Server The device responsible for interfacing with the camera to acquire images.

Note. The design needs to be tailored to the testing speed and sampling frequency of the steel pipe.

3.3 Inference server A device for detecting and classifying defects in real-time images of the steel pipe surface.

Note. The server performance meets the requirements for real-time performance, data querying, storage, and other aspects.

3.4 User terminal The software provides users with various surface quality features, including defect alarms, defect distribution previews, and historical data queries, as well as a systematic approach. A device that performs functions such as system maintenance and defect sample collection.

3.5 Line structured light three-dimensional depth detection 3D reconstruction is performed based on the principle of triangulation. During image acquisition, the line laser beam projects onto a plane of light; for...