Article
Engineering, Mechanical
Jancler Adriano Pereira Nicacio, Fernando Castro Oliveira, Marcello Rosa Dumont
Summary: Crude oil is a complex mixture of hydrocarbons and impurities. This study investigated the failure of a shell-and-tube heat exchanger in a diesel hydrotreating unit of a Brazilian oil refinery, and identified ammonium chloride corrosion as the root cause. The results showed that 317L austenitic stainless steel exhibits high corrosion resistance in media containing ammonium chloride.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xingwang Sheng, Chao Lin, Weiqi Zheng, Zhihui Zhu, Xu Song
Summary: This study conducted a series of fatigue tests to establish a fatigue life database for steel rebars joined by flash butt welding, and used machine learning models to analyze and predict the fatigue life. The results showed the superior performance of the ANN model, and identified the main factors influencing the fatigue life of steel rebars joined by flash butt welding.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jun Cao
Summary: This study investigates the effect of hydrogen embrittlement on the safety assessment method for low-strength hydrogen transmission pipelines. The results show that hydrogen embrittlement has a more sensitive influence on the tensile properties of the base material than on the weld joint. The safety assessment method for defective pipes needs to consider the effect of hydrogen embrittlement.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xiaohe Wang, Zengqiang Cao
Summary: This paper presents a dynamic installation (DI) method based on electromagnetic force to reduce damage to composite laminates and improve joint performance. The study shows that DI can effectively decrease installation resistance, reduce severe damage to laminates, and improve stress distribution in the joint.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jitong Cui, Yingying Kong, Cuiwei Liu, Baoping Cai, Faisal Khan, Yuxing Li
Summary: This paper presents a method for quantifying the failure probability of hydrogen doped pipelines and utilizes Bayesian network for quantitative calculation. The results show that this method can more accurately assess the failure probability of hydrogen doped pipelines and provide a decision basis for preventing failure accidents.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Zhiqiang Li, Jie Li, Cen Li, Xiaodong Xie, Zhiyong Yang
Summary: In this study, the microstructure evolution of the material in the hot spot area of the high-speed train brake disc was observed and the mechanism of mechanical property degradation was obtained through tensile tests. The research results provide guidance for crack damage identification of the brake disc and condition-based maintenance.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Lijia Luo, Yincheng Wang, Wei Chen, Zuming Zhao, Wenfei Chen, Shiyi Bao
Summary: Tube-to-tube impact wear is a significant factor in the failure of alloy 690 tubes in nuclear steam generators. This paper investigates the wear damage mechanism and detection method of alloy 690 tubes under tube-to-tube impact loads. The results reveal the wear damage mechanism through analysis of macro and micro morphologies as well as metallographic structures. A nonlinear ultrasonic wave mixing method is proposed for damage detection and a detection device is developed to implement this method. Experimental results indicate that the damage mode of tube-to-tube impact wear varies with impact load and cycle number, and the nonlinear modulation index is effective in assessing the damage degree of alloy 690 tubes.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Bo Min, Xu Zhang, Chengping Zhang, Xuan Zhang
Summary: This paper investigates the failure performance of cracked lining structures and develops a neural network model to forecast the load-bearing capacity loss in cracked double-arch tunnels. The results show that cracks cause localized crushing failure in the linings, leading to a significant reduction in the tunnels' load-bearing capacity. The depth of the cracks is the main factor influencing the capacity decrease in double-arch tunnels.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Ruiyi Jiang, Jiang Feng, Min Hou, Hougai Shi, Zhenyu Qiu, Hualin Fan
Summary: Through field explosion experiments, it was found that shield tunnelling segments with different reinforcement ratios exhibit varying levels of damage during explosions, which have different impacts on the structural load-bearing capacity. Modestly increasing the reinforcement ratio can effectively enhance its blast resistance.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Aydin Buyuksarac, Erdem Gundogdu, Ozcan Bektas, Ercan Isik
Summary: This study successfully identified the structural lineations of the study area through remote sensing image processing and derivation from aeromagnetic data, and found lineament distributions consistent with known fault orientations. The study also revealed the shearing effect between the Tuzgolü Fault and the Ecemis Fault, indicating the development of a wrench tectonics mechanism in the area. The orientation and location of the faults were accurately determined through tilt transformation of the magnetic anomaly map.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Wenwei Wang, Kai Wang, Xiaoqiang Zhang, Yulong Jiang, Tingting Cai, Jianbing Yan, Shaofei Yue
Summary: This study investigates the mechanical properties and failure mechanism of coal seams under the action of ScCO2. The results show that ScCO2 promotes plastic failure of the coal mass, affecting the storage structure of coal seams and accelerating their failure process.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Yiping Jiang, Maoru Chi, Jungang Yang, Liangcheng Dai, Yuchen Xie, Zhaotuan Guo
Summary: This article investigates and simulates the derailment of empty freight trains at the switch section of a turnout in the diverging route, and proposes preventive measures. The results show that the derailment is caused by the combined effect of various factors, and reducing the longitudinal coupler force and the wheel rail friction coefficient can decrease the possibility of derailment. Additionally, installing a guard rail in front of the turnout can effectively prevent derailment.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Lisha Liang, Xibing Li, Quanqi Zhu, Siyu Peng, Xuefeng Si
Summary: Understanding the stress distribution and failure characteristics around a U-shaped cavern is important for the stability analysis of rock structures. This study analyzed the stress distribution based on complex variable theory and conducted numerical simulations to study the failure process and energy evolution of a U-shaped cavern with different height-to-width ratios. The results show that the height-to-width ratio affects the stress concentration and failure process of the cave walls, vault, and floor. The direction of the maximum principal stress also influences the stability and failure characteristics of the cavern. Therefore, the design of the support system for U-shaped caverns should consider both the height-to-width ratio and the direction of the maximum principal stress.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Juan Jose Jimenez de Cisneros Fonfria, Ester Olmeda, Susana Sanz, Maria Garrosa, Vicente Diaz
Summary: Energy absorbing devices in vehicles can partially transform impact energy and protect passengers. In this paper, the failure analysis of the underframe crumple zone in a train car was conducted through finite element simulations, showing that the component acted properly after the impact.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Yitao Li, Chunxia Chen, Liming Yao, Mu Fan, Yanmei Zhang
Summary: This study aims to investigate the failure pressure of corroded gas pipelines under the combined effects of global bending and temperature difference. The results show that the service life of gas pipelines can be reduced by the factors of global bending strain and temperature difference. The chosen corrosion rate model and key parameters also play important roles in affecting the pipeline's service life.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Mengke Zhao, Jian Rui Feng, Qian Li, Shouxiang Lu, Jin Lin
Summary: The failure mechanisms of BGA packages in fire smoke environments are of paramount importance for the recovery and maintenance of electronic devices post-fire. This study reveals that nitrile-butadiene rubber and polycarbonate smoke do not affect the electrical conductivity of BGA packages, while polyvinyl chloride smoke causes insulation failure and permanent open-circuit failure due to corrosion products in solder joints.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jie Fu, Huashan Liu, Lisha Feng, Dun Wu, Huan Tang, Yimin Xia
Summary: The wear failure of disc cutter rings is a crucial factor affecting the efficiency of TBM construction. This study conducted experiments to compare the wear behavior of modified cutter ring materials and analyzed the reasons for the improved wear resistance. The results showed that the increased carbide content in the modified material was the main reason for its excellent wear resistance.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xiao Zhang, Li Yu, Mingnian Wang, Henghong Yang
Summary: This paper investigates the mechanical response and failure characteristics of tunnels subjected to reverse faulting. A theoretical model is established to analyze the bending moment, shear force, and safety factor of the tunnels. The model is verified through numerical simulations, and the results show good agreement. A parametric analysis is presented to explore the effects of fault displacement, fault zone width, and displacement ratio on the tunnels. The ultimate fault displacement for different failure modes is estimated and variations in the fault displacement ratio result in changes in internal forces and potential failure ranges.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jiding Zhang, Keke Zhao, Hongda Yang, Yue Sheng, Xiaoyu Jiang
Summary: This article proposes a theoretical calculation method for the fracture of hydrogen-induced nanocrystalline (NC) materials based on the discrete dislocation method. It also introduces the theory of hydrogen inhibiting dislocation emission and studies the pinning effect of hydrogen on dislocation. The results show that hydrogen promotes the fracture of crystal materials.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xinyan Jin, Kai Wang, Hongwei Qian
Summary: This study investigated the root cause of an abnormal premature groove-clogging failure on a sink roll in a hot-dip galvanizing line. It was found that the failure was caused by the buildup of a large amount of Fe2Al5Znx dross in the grooves, and the key factor was the control of Tstrip.
ENGINEERING FAILURE ANALYSIS
(2024)
