What are the nondestructive testing requirements for weld quality grades? What are the ultrasonic testing standards for steel structure welds?

Release Date:

2021/07/10

Classification of Weld Quality Grades and Nondestructive Testing Requirements: Welds shall be assigned different quality grades in accordance with the following principles, based on factors such as the structural importance, load characteristics, weld configuration, service environment, and stress state. 1. In components subject to fatigue analysis, all butt welds shall be fully penetrated, with the following quality grades: (1) Transverse butt welds or T-joint combinations of butt and fillet welds in which the applied force is perpendicular to the weld length—when subjected to tension, they shall be Grade 1; when subjected to compression, they shall be Grade 2; (2) Longitudinal butt welds in which the applied force is parallel to the weld length shall be Grade 2. 2. In components not subject to fatigue analysis, any butt weld required to have strength equal to that of the base metal

What are the nondestructive testing requirements for weld quality grades? What are the ultrasonic testing standards for steel structure welds?

Weld Joint Classification and Nondestructive Testing Requirements:

Welds shall be assigned different quality grades in accordance with the following principles, based on factors such as the structural importance, load characteristics, weld configuration, service environment, and stress state.

1. In components subject to fatigue analysis, all butt welds shall be fully penetrated, and their quality grade shall be

1) For transverse butt welds or T-shaped combined butt-and-fillet welds in which the applied force is perpendicular to the weld length, the weld quality grade shall be Grade 1 under tension and Grade 2 under compression.

2) Longitudinal butt welds in which the applied force is parallel to the weld length shall be classified as Grade 2.

2. For components not subject to fatigue analysis, all butt welds required to have strength equal to that of the base metal shall be fully penetrated; the quality grade of such welds shall be no lower than Grade 2 under tensile loading and preferably Grade 2 under compressive loading.

3. For crane girders in heavy-duty service and with a lifting capacity Q ≥ 50 t, full penetration is required for both the T-joint welds between the web of the girder and the flange, and the T-joint welds between the top chord of the crane truss and the gusset plate. The weld configuration is typically a combination of butt and fillet welds, and the weld quality grade shall not be lower than Grade II.

4. For ‘I’-shaped joints that do not require full penetration, the fillet welds or partial-penetration combination welds of butt and fillet joints, as well as fillet welds used in lap joints, shall be assigned the following quality grades:

1) For structures that directly withstand dynamic loads and require fatigue verification, as well as for crane girders in service classes with a medium duty cycle and crane lifting capacities of 50 t or more, the visual quality standards for welds shall comply with Grade II.

2) For other structures, the visual quality standard for welds may be Grade 2.

Visual inspection is generally performed by the naked eye; crack detection should be supplemented with a 5× magnifying glass under appropriate lighting conditions, and magnetic particle or penetrant testing may be employed when necessary. Dimensional measurements shall be carried out using measuring instruments and gauges.

I. Quality Grades and Defect Classification for First- and Second-Level Welds:

What are the nondestructive testing standards for steel structure welds?

For fully penetrated welds, the inspection criteria for internal defects are as follows:

1. Class I welds shall be subject to 100% inspection, with acceptance criteria requiring that the inspection result meet Level II or higher as specified in Class B of the current national standard “Manual Ultrasonic Testing Methods and Quality Grading for Steel Welds” (GB 11345).

2. Second-level welds shall be subject to random inspection, with the inspection rate not less than 20%; the acceptance grade for such inspections shall be Level III or higher as specified in Class B of the current national standard “Manual Ultrasonic Testing Methods and Quality Grading for Steel Welds” (GB 11345).

3. Full-penetration Class III welds are exempt from nondestructive testing.

4. The ultrasonic testing methods and defect classification for welds in welded spherical-knot space frames shall comply with the provisions of the current national standard JG/T 203-2007, “Ultrasonic Testing and Quality Grading Method for Steel Structures.”

5. The ultrasonic testing methods and defect classification for welds in bolted spherical node space frames shall comply with the provisions of the current national standard JG/T 203-2007, “Ultrasonic Testing and Quality Grading Method for Steel Structures.”

6. In addition to complying with the relevant provisions of Clause 7.3.3 of GB 50205-2001, the non-destructive testing results for the electroslag-welded seams of box-section web plates shall also be evaluated in accordance with Appendix C for weld penetration width and weld misalignment.

7. The ultrasonic testing methods and defect classification for welds at T-, K-, and Y-shaped circular tube joints shall comply with the provisions of Appendix D of GB 50205-2001.

8 When the design documents specify radiographic or ultrasonic testing but such methods are unable to determine the nature of defects, radiographic testing may be employed for inspection and verification.

9. Radiographic testing shall comply with the provisions of the current national standard “Radiographic Examination and Quality Grading of Fusion-Welded Butt Joints in Steel” (GB 3323), and the quality grade of radiographic images shall meet the requirements for Class A or Class B. For Class I welds, the acceptance criterion shall be Level II or higher as specified in “Radiographic Examination and Quality Grading of Fusion-Welded Butt Joints in Steel” (GB 3323); for Class II welds, the acceptance criterion shall be Level III or higher as specified in the same standard.

Full Text | Measures for the Supervision and Administration of Inspection and Testing Institutions

Ultrasonic Phased Array Technology

Full Text | Measures for the Supervision and Administration of Inspection and Testing Institutions

Ultrasonic Phased Array Technology

To further carry forward the spirit of Lei Feng and promote the volunteer ethos of “dedication, friendship, mutual assistance, and progress,” in accordance with the spirit of the Henan Provincial Association for Science and Technology’s “Notice on Launching a Centralized ‘i-Science Popularization’ Science and Technology Volunteer Service Campaign in the Spirit of Lei Feng,” Luoyang Weicheng Engineering Testing Co., Ltd. responded enthusiastically to the call and organized a science popularization event on the safe operation of forklifts. On March 4, our company meticulously planned and conducted an emergency response drill for special equipment—forklift accidents—and invited several nearby companies that use forklifts to observe the exercise. The purpose of this drill was to simulate real-world working conditions, specifically the sudden occurrence of an accident during the process of using a forklift to handle goods.

2024-03-05

The 10th Anniversary Gratitude Celebration of Luoyang Weicheng Engineering Testing Co., Ltd. Concludes Successfully

On the afternoon of December 29, 2023, Weicheng Testing Co., Ltd. held a grand gratitude celebration—“Our Ten Years”—inviting distinguished guests, including Mr. Jia Hong, Director and Vice Chairman of the Titanium-Zirconium Industry Development and Application Center of the China Equipment Management Association, as well as Mr. Lu Fusheng, Executive Deputy Director, Vice Chairman, and Secretary-General, along with clients and partners, to jointly witness this milestone occasion. The first segment of the event: A Decade of Development The event officially commenced at 2:00 p.m., with the company welcoming all attendees

2024-01-11

In 2023, Luoyang Weicheng Engineering Testing Co., Ltd. Successfully Held the “Intensive Training and Competition” — Gamma-Ray Radiographic Inspection Emergency Drill

On October 11, Luoyang Weicheng Engineering Testing Co., Ltd. held a large-scale training and competition—specifically, a γ-ray radiographic inspection radiation emergency response drill—under the theme “Everyone Talks About Safety, Everyone Knows How to Respond to Emergencies.” The event invited leaders from the provincial, municipal, and district levels to attend and observe. Prior to the start of the emergency response drill, Cui Songbiao, General Manager of Luoyang Weicheng Engineering Testing Co., Ltd., and Gong Aifeng, Deputy General Manager, extended a warm welcome to the visiting provincial, municipal, and district leaders and pledged that Weicheng Testing would consistently focus on enhancing its professional technical expertise and emergency response capabilities as key drivers for corporate safety management.

2023-10-19

Return to list

Address: Room 104, Building 9, Futong Intelligent Manufacturing Industrial Park, Jinye 1st Road, Yiyang County, Luoyang City, Henan Province

Phone:+86-379-66915081 +86-379-66915005

Email:lywcjc@lywcjc.cn

Fax:+86-379-66919852

Website:www.lywcjc.cn

WeChat

Yu Public Security Bureau Filing No. 41030602000129

COOKIES

Our website uses cookies and similar technologies to personalize the advertising shown to you and to help you get the best experience on our website. For more information, see our Privacy & Cookie Policy

COOKIES

required

These cookies are necessary for basic functions such as payment. Standard cookies cannot be turned off and do not store any of your information.

analyze

These cookies collect information, such as how many people are using our site or which pages are popular, to help us improve the customer experience. Turning these cookies off will mean we can't collect information to improve your experience.

Feature

These cookies enable the website to provide enhanced functionality and personalization. They may be set by us or by third-party providers whose services we have added to our pages. If you do not allow these cookies, some or all of these services may not function properly.

advertise

These cookies help us understand what you are interested in so that we can show you relevant advertising on other websites. Turning these cookies off will mean we are unable to show you any personalized advertising.