Journal of Pipeline Science and Engineering最新文献_第2页

Characterization and potential distribution mapping of cathodically protected buried pipelines based on homogeneous and heterogenous factors 基于均质与非均质因素的阴极保护埋地管道表征与电位分布映射

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2025-08-31 DOI: 10.1016/j.jpse.2025.100350

Reece Goldsberry, Homero Castaneda

{"title":"Characterization and potential distribution mapping of cathodically protected buried pipelines based on homogeneous and heterogenous factors","authors":"Reece Goldsberry, Homero Castaneda","doi":"10.1016/j.jpse.2025.100350","DOIUrl":"10.1016/j.jpse.2025.100350","url":null,"abstract":"<div><div>The use of a close interval potential survey (CIPS) for cathodically protected buried pipelines can provide useful information about the active or passive state of the pipeline/coating interface and the level of protection. Various models have been used to describe the potential distribution for these systems under the assumption that the coating characteristics and soil conditions are homogenous over the selected Right of Way. To allow for the inherent heterogeneity of these parameters, a transmission line model (TLM) was developed to determine the potential distribution along the soil-pipeline interface numerically. Numerical analysis of the TLM showed the model's sensitivity for both heterogeneous and homogeneous soil and coating conditions, such as different impedance and current leakage. For validation of the model, the model’s output was compared to measured CIPS values for various impressed current cathodically protected buried pipelines. The model’s output was able to follow the general trend of the field CIPS data. This provides insight into the distribution of coating impedance along the length of the two pipelines. Two case studies were performed to show the impact of various environmental and/or physical factors that can affect the effectiveness of a cathodic protection system. It was shown that the model could be used to either extract the state of the coating, helping to identify possible regions of low impedance which could be attributed to holidays/defects present in the coating from CIPS data, or if given real-world factors, it can be used for the design and integration of cathodic protection (CP) systems.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100350"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An MILP model for the coupled design and operation optimization of large-scale gathering pipeline networks 大型集输管网耦合设计与运行优化的MILP模型

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2025-09-03 DOI: 10.1016/j.jpse.2025.100359

Shiyuan Pan, Huanyu Zhao, Haochong Li, Yu Geng, Jian Du, Zhuochao Li, Pengtao Niu, Zexin Zhang, Fengyuan Yan, Ning Xu, Yongtu Liang

{"title":"An MILP model for the coupled design and operation optimization of large-scale gathering pipeline networks","authors":"Shiyuan Pan, Huanyu Zhao, Haochong Li, Yu Geng, Jian Du, Zhuochao Li, Pengtao Niu, Zexin Zhang, Fengyuan Yan, Ning Xu, Yongtu Liang","doi":"10.1016/j.jpse.2025.100359","DOIUrl":"10.1016/j.jpse.2025.100359","url":null,"abstract":"<div><div>The optimization of gathering pipeline networks (GPNs) involves both design and operation, which are highly interdependent but often addressed separately, leading to suboptimal solutions and higher costs. For the most common multilayer star-tree (MLST) and multilayer tree (MLT) gathering pipeline networks, an mixed-integer linear programming (MILP) approach is developed that integrates detailed hydraulic and temperature calculations with on-site gathering processes to couple design and operation optimization. This method accounts for constraints such as MLST and MLT topology, hydraulic and temperature calculations, flow balance, equipment layout, energy consumption, and the pre-water separation process. The objective function minimizes the overall construction and annual operational costs of the GPN, determining the optimal pipeline layout, pipe diameters, equipment selection and placement, operational schemes, and the operating pressures and temperatures at each node. The proposed method is validated on two large-scale real oilfields. In Case 1, our approach reduces construction and operational costs by 17.4% and 12.5%, respectively, compared to the benchmark method, while achieving a 42.8% reduction in carbon emissions compared to the actual oilfield scheme. In Case 2, the method achieves a 16.6% reduction in construction costs, a 66.3% reduction in operational costs, and a 66.8% reduction in carbon emissions compared to the real oilfield scheme. Moreover, compared to the modified benchmark method, our approach delivers similar construction costs while further decreasing annual operational costs and carbon emissions by 9.5% and 9.6%, respectively. These results demonstrate that the proposed method enhances both economic and environmental performance in large-scale oilfield GPNs.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100359"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transformation mechanism of martensite-austenite (M-A) constituent in the heat-affected zone of high strength pipeline steel and its correlation with toughness deterioration 高强管线钢热影响区马氏体-奥氏体相变机理及其与韧性劣化的关系

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2025-09-04 DOI: 10.1016/j.jpse.2025.100358

Xueda Li, Chunyu Li, Qingqing Wang, Xiangyu Dong, Liying Li, Bin Han

{"title":"Transformation mechanism of martensite-austenite (M-A) constituent in the heat-affected zone of high strength pipeline steel and its correlation with toughness deterioration","authors":"Xueda Li, Chunyu Li, Qingqing Wang, Xiangyu Dong, Liying Li, Bin Han","doi":"10.1016/j.jpse.2025.100358","DOIUrl":"10.1016/j.jpse.2025.100358","url":null,"abstract":"<div><div>Martensite-austenite (M-A) constituent in the heat-affected zone (HAZ) usually plays a detrimental role in toughness, especially in the intercritically reheated coarse-grained (ICCG) HAZ. However, its transformation mechanism has been rarely investigated. In the present study, transformation process of reverted austenite (γ<sub>r</sub>) formed at different second pass peak temperatures (<em>T</em><sub>p2</sub>) was studied through interrupt quenching and multi-scale characterizations on decomposition products of γ<sub>r</sub>. And the correlation between transformation mechanism, final status (size, distribution and hardness) of M-A constituent and toughness deterioration was discussed. The results showed that distinct volume fraction and carbon enrichment of γ<sub>r</sub> formed at different <em>T</em><sub>p2</sub> determined subsequent phase transformation process. Lower <em>T</em><sub>p2</sub> induced small reverted fraction and higher carbon content of γ<sub>r</sub>, which continuously distributed along coarse grain boundaries, and the final M-A constituent inherited the continuous distribution and high carbon content of γ<sub>r</sub>, which yielded high M-A hardness and deteriorated the toughness. Higher <em>T</em><sub>p2</sub> triggered larger fraction of γ<sub>r</sub> with lower carbon content, and M-A constituent was subdivided or dispersed by decomposition product of γ<sub>r</sub> (ferrite, bainite and acicular ferrite). The sizes of M-A and decomposed products were also refined. Dispersed and refined M-A with lower hardness could notably mitigate the toughness deterioration of ICCGHAZ.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100358"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A review of the challenges, solutions and economics of hydrogen transmission in steel pipelines 钢管道氢气传输的挑战、解决方案和经济性综述

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2026-01-28 DOI: 10.1016/j.jpse.2026.100451

Eoghan Summers, Julia Race, Mohammed Alaa Almoghayer, Dimitri Mignard

{"title":"A review of the challenges, solutions and economics of hydrogen transmission in steel pipelines","authors":"Eoghan Summers, Julia Race, Mohammed Alaa Almoghayer, Dimitri Mignard","doi":"10.1016/j.jpse.2026.100451","DOIUrl":"10.1016/j.jpse.2026.100451","url":null,"abstract":"<div><div>Developing transmission pipelines is considered essential to realising renewable hydrogen’s decarbonisation potential in industry, transport, and energy storage. Numerous studies identify pipelines as the most cost-effective option for transporting hydrogen compared with alternative hydrogen carriers and with electricity transmission when hydrogen is the final energy carrier. However, hydrogen’s interaction with steel presents significant technical challenges: it can diffuse into pipeline materials, reducing ductility and fracture toughness and accelerating fatigue crack growth, particularly in high-strength steels at pressures typical in transmission. These risks are exacerbated by pressure cycling arising from variable hydrogen supply. Additionally, hydrogen’s lower volumetric energy density reduces throughput and linepack capacity, complicating system balancing and security of supply. Mitigation strategies include lower-strength steels, pressure limitation, inhibitor gases and coatings, and buffer storage to smooth operating profiles. This review finds current techno-economic studies often omit some challenges and mitigations in cost estimates, indicating a need for more comprehensive modelling.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100451"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sand transport characteristics and critical sand-carrying velocity of gas-water mixtures in wellbores during hydrate production 水合物开采过程中井内气水混合物输砂特性及临界携砂速度

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2026-03-04 DOI: 10.1016/j.jpse.2026.100470

Junyu Deng, Rui Zhang, Huan Mu, Jian Liu, Xudong Zhao, Yufei Song, Yuquan Li, Jialin Shi

{"title":"Sand transport characteristics and critical sand-carrying velocity of gas-water mixtures in wellbores during hydrate production","authors":"Junyu Deng, Rui Zhang, Huan Mu, Jian Liu, Xudong Zhao, Yufei Song, Yuquan Li, Jialin Shi","doi":"10.1016/j.jpse.2026.100470","DOIUrl":"10.1016/j.jpse.2026.100470","url":null,"abstract":"<div><div>Sand production in weakly cemented silty-fine sediments poses a significant challenge to the stable and efficient operation of horizontal hydrate production wells. This study moves beyond site-specific observations to elucidate the fundamental gas-water-sand multiphase transport mechanisms through systematic laboratory simulations. By examining the coupled influence of inclination angles and gas-liquid ratios (GLR), the evolution of particle-fluid interactions was characterized. Results reveal three distinct transport regimes: wall-concentrated, critical, and wall-dispersed flow. A critical deviation angle of 55° was identified, at which the sand-carrying capacity reaches its minimum. This phenomenon is mechanistically attributed to the extremum in the transverse gravitational component and interfacial friction, which maximizes particle slippage. Quantitatively, the transport efficiency exhibits a nonlinear dependence on GLR, with a critical threshold around 50, beyond which further increases provide limited enhancement in gas-phase drag. Furthermore, the critical sand-carrying velocity is found to be physically coupled with the churn-to-annular flow transition, where the motive force shifts from liquid-phase buoyancy to gas-phase shear. A mechanistic-empirical model was established with high fidelity (<em>R</em><sup>2</sup> = 0.99577), demonstrating a liquid-phase saturation effect where additional liquid volume provides negligible gains in carrying capacity. These findings provide a scalable theoretical framework and precise operational envelopes for optimizing sand management strategies in marine hydrate recovery.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100470"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of oxygen and nitrogen on hydrogen adsorption and permeation processes 氧和氮对氢气吸附和渗透过程的影响

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2025-09-14 DOI: 10.1016/j.jpse.2025.100377

Lin Chen, Meng Sun, Shiwen Guo, Boxing Han, Heng Liu, Haozhi Wu, Shaohua Dong, Keke Song

引用次数: 0

Dynamic response of buried pipeline under the sliding instability of slopes in cold regions 寒区边坡滑动失稳条件下埋地管线的动力响应

IF 5

Journal of Pipeline Science and Engineering Pub Date : 2026-07-01 Epub Date: 2025-08-26 DOI: 10.1016/j.jpse.2025.100344

Qiaozhen Li, Chao Wang, Chao Sun, Min Luo, Hao Wang, Haoming Liu

{"title":"Dynamic response of buried pipeline under the sliding instability of slopes in cold regions","authors":"Qiaozhen Li, Chao Wang, Chao Sun, Min Luo, Hao Wang, Haoming Liu","doi":"10.1016/j.jpse.2025.100344","DOIUrl":"10.1016/j.jpse.2025.100344","url":null,"abstract":"<div><div>In order to study the dynamic response behavior of buried pipelines under the instability and sliding of slopes in cold regions, the buried pipelines in cold regions are taken as the research object. Considering the characteristics of large deformation and collapse of unstable soil, the material nonlinear characteristics of pipeline and foundation soil, and the contact nonlinear characteristics among pipeline, unstable slope and foundation soil, the nonlinear dynamic model of buried pipeline under slope instability is established by SPH-FEM (smoothed particle hydrodynamics-finite element method) method. Compared with the literature results, the maximum error is 0.67%, which verifies the rationality of the model and algorithm. Then, pipeline’s dynamic response with different influencing factors are studied. The results show that: The residual stress of pipeline decreases with the increase of pipeline position, with the decrease of diameter-to-thickness ratio of pipeline, and increases first and then decreases with the increase of freezing depth of foundation soil, with the variation amplitude of residual stress of 12.72%, 23.1% and 14.56% respectively. The pipeline displacement varies with different influencing factors, the maximum variation in the freezing depth of foundation soil can reach 22.6 mm, while in the diameter-to-thickness ratio and pipeline position can reach 6.9 mm and 5.4 mm respectively. The degree of local dent of the pipeline is most pronounced at the peak time,when the freezing depth of the foundation soil is 0 m, the local dent depth can reach 4.92% of the pipeline’s outer diameter. Relevant research methods are expected to provide guidance for the integrity management of slope pipeline engineering in cold regions.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 4","pages":"Article 100344"},"PeriodicalIF":5.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148528871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterizing properties of pipeline girth welds: A novel testing protocol and validation 管道环焊缝特性表征：一种新的测试方案和验证

IF 4.9

Journal of Pipeline Science and Engineering Pub Date : 2026-05-01 Epub Date: 2025-11-03 DOI: 10.1016/j.jpse.2025.100399

Tieyao Zhang , Yi Shuai , Ye Tian , Zhiyang Lv , Mengchao Hu , Jian Shuai , Laibin Zhang

{"title":"Characterizing properties of pipeline girth welds: A novel testing protocol and validation","authors":"Tieyao Zhang , Yi Shuai , Ye Tian , Zhiyang Lv , Mengchao Hu , Jian Shuai , Laibin Zhang","doi":"10.1016/j.jpse.2025.100399","DOIUrl":"10.1016/j.jpse.2025.100399","url":null,"abstract":"<div><div>Accurate, region-specific mechanical properties of pipeline girth welded joints are fundamental for structural safety design and integrity assessment. This study focuses on X80 pipeline girth welded joints, integrating microstructure analysis, small-scale in-situ tensile tests, full-wall-thickness tensile experiments, and finite element (FE) simulations to validate the necessity and accuracy of refined mechanical parameter testing across joint regions. Based on the Gurson-Tvergaard-Needleman (GTN) damage model, region-specific parameters of the girth welded joint were precisely calibrated and applied to FE models. Results indicate that the refined partitioned FE models closely replicate experimental load-displacement curves, strain distributions, fracture initiation points, and crack propagation paths. Geometric discontinuities and material weaknesses in the coarse-grained heat-affected zone (CGHAZ) were identified as primary contributors to strain concentration and joint failure under tension load. This work establishes a methodological framework for refined mechanical characterization and fracture analysis of high-grade pipeline girth welds, providing an important reference for safety design and structural integrity assessment.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 3","pages":"Article 100399"},"PeriodicalIF":4.9,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147757004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A comparative study on the effect of GMAW welding current on the performance of API 5 L GrB pipeline steel welds for oil and gas industrial applications GMAW焊接电流对石油天然气工业用API 5l GrB管线钢焊缝性能影响的对比研究

IF 4.9

Journal of Pipeline Science and Engineering Pub Date : 2026-05-01 Epub Date: 2025-09-03 DOI: 10.1016/j.jpse.2025.100360

Akan Peter , James Mutua , Japheth Obiko , Joshua Ngoret

{"title":"A comparative study on the effect of GMAW welding current on the performance of API 5 L GrB pipeline steel welds for oil and gas industrial applications","authors":"Akan Peter , James Mutua , Japheth Obiko , Joshua Ngoret","doi":"10.1016/j.jpse.2025.100360","DOIUrl":"10.1016/j.jpse.2025.100360","url":null,"abstract":"<div><div>The reliability of oil and gas transportation depends heavily on weld quality during pipeline construction. This study investigates the effect of gas metal arc welding (GMAW) current on API 5 L GrB pipeline weld joint. Welding experiments were conducted using currents from 140 A to 170 A, at constant voltage of 22 V and welding speed of 6 m/min. Finite Element Modelling (FEM) simulations were performed using Simufact Welding 6.0 software to compare with experimental data. Results showed that an increase in welding current improved penetration depth (91.35% to 124.95%) and weld width (15.17 mm to 16.12 mm), before declining to 12.32 mm at 170 A. 170 A caused undercutting and sagging, while 140 A resulted in incomplete penetration. Microstructural analysis revealed grain coarsening at higher currents, with acicular ferrite dominating the fusion zone and mixed ferrite morphologies in the HAZ. The fusion zone at 170 A exhibited a micro-hardness of 260 HV<sub>0.3</sub>, exceeding the 248 HV<sub>0.3</sub> limit for API 5 L GrB, increasing susceptibility to hydrogen-induced cracking (HIC) and stress-corrosion cracking (SCC). Residual stress shifted from −228 ± 7.5 MPa in the base metal to −268.73 ± 8.5 MPa at 150 A, then decreased to −182.7 ± 13.4 MPa at 160 A and −118.3 ± 13 MPa at 170 A. Simulation results closely matched the experiment, with deviations of 6.72%, 4.08%, and 12% for weld width, depth, and residual stress, respectively. The study supports the combined utilisation of physical and computational tools to optimise pipeline welding performance.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 3","pages":"Article 100360"},"PeriodicalIF":4.9,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147757006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Cr content on softening mechanism of the heat-affected zone of X80 GMAW automatic girth weld Cr含量对X80 GMAW自动环焊缝热影响区软化机理的影响

IF 4.9

Journal of Pipeline Science and Engineering Pub Date : 2026-05-01 Epub Date: 2025-05-16 DOI: 10.1016/j.jpse.2025.100298

Zifeng Zhao , Feng Wang , Gang Wei , Zhikui Li , Lianshuang Dai , Longyi Zhao , Xunyun Lv , zhangyi She , Xiangyu Dong , Bin Han , Xueda Li

{"title":"Effect of Cr content on softening mechanism of the heat-affected zone of X80 GMAW automatic girth weld","authors":"Zifeng Zhao , Feng Wang , Gang Wei , Zhikui Li , Lianshuang Dai , Longyi Zhao , Xunyun Lv , zhangyi She , Xiangyu Dong , Bin Han , Xueda Li","doi":"10.1016/j.jpse.2025.100298","DOIUrl":"10.1016/j.jpse.2025.100298","url":null,"abstract":"<div><div>Softening of the heat-affected zone (HAZ) could lead to strain concentration in the girth weld joint, which endangers the service safety of high strength pipelines, while the chemical composition and original microstructure of pipeline steel play a determining role in its softening behavior. In this study, X80 pipeline steels with different Cr contents but identical manufacturing processes were girth welded using automatic gas metal arc welding (GMAW). Microhardness, microstructure, grain size, dislocation density and precipitation of both base metal and the HAZ were analyzed to reveal the influence of Cr content on the softening mechanism. The results showed that with the increase of Cr content from 0.115 % to 0.216 %, the HAZ softening ratio decreased from 11.00 % to 3.48 %. The steel with higher Cr content exhibited fine acicular ferrite (AF) dominated microstructure, which introduced higher dislocation density and refined polygonal ferrite grains in the softening zone, whereas lower Cr content led to granular bainite (GB) dominated structure with inferior softening resistance. Precipitates showed no significant difference between the two steels. Relatively higher Cr content and AF fraction in base metal is beneficial to its anti-softening behavior in the HAZ.</div></div>","PeriodicalId":100824,"journal":{"name":"Journal of Pipeline Science and Engineering","volume":"6 3","pages":"Article 100298"},"PeriodicalIF":4.9,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147757110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0