The National Pipeline Research Institute has successfully conducted the first domestic residual stress testing on large-diameter, high-grade oil and gas pipeline circumferential welds. This achievement, made possible through the use of the neutron diffraction instrument at the China Spallation Neutron Source (CSNS), significantly enhances the safety of the nation's oil and gas pipeline transportation and contributes to energy security.
The testing conducted in December 2024, utilized advanced neutron diffraction technology to accurately reveal the distribution characteristics of residual stresses within the circumferential welds. By analyzing the results, researchers identified optimal welding parameters that ensure consistent residual stress across various parts of the pipeline. This data is crucial for conducting reliable assessments of weld integrity and optimizing welding processes.
This initiative not only introduces a novel testing technique to the field of pipeline research, but also highlights the critical role of national scientific infrastructure in supporting major research projects. Furthermore, it provides a valuable application model for scientific inquiries related to oil and gas pipelines, both domestically and internationally, that employ neutron diffraction testing.
The CSNS stands as a robust research platform across multiple disciplines, including materials science, physics, chemistry, life sciences, environmental resources, and new energy technologies. It is the world's fourth pulsed spallation neutron source. The neutron diffraction technique developed at CSNS offers significant advantages for non-destructive testing of residual stresses: it achieves greater penetration depth of up to several centimeters and high spatial resolution, enabling accurate characterization of internal stress gradients and three-dimensional stress measurements. Additionally, the technology allows for simulated loading conditions mimicking both manufacturing and service environments, thereby facilitating in-situ analysis of multi-scale residual stress distributions.
To accomplish this task, the team led by Li Xiaohu at the CSNS collaborated closely with the National Pipeline Research Institute. They developed specialized measurement tools suitable for large pipeline components, ensuring precise sample positioning and the simulation of complex environments during testing. The team also completed a visual simulation of the experimental measurements, guaranteeing the accuracy and reliability of the data, which effectively ensured the smooth progression of the testing work.
This groundbreaking work is set to bolster the safety and reliability of China's energy infrastructure, supporting the high-quality development of the nation's energy sector.
Reporter | Xie Maishi
Photo | CSNS, Nanfang Plus
Editor | Liu Lingzhi, James, Shen He, Zhang Ying
