Engineering Failure Analysis最新文献_第10页

Fatigue of Ti6Al4V manufactured by PBF-LB: A comparison of failure mechanisms between net-shape and electro-chemically milled surface conditions

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-14 DOI: 10.1016/j.engfailanal.2025.109403

Tatiana Risposi , Lorenzo Rusnati , Luca Patriarca , Alex Hardaker , Dawid Luczyniec , Stefano Beretta

In the recent years, metal additive manufacturing (AM) has acquired large interest for many industrial applications, principally due to the capability to produce parts with complex geometry. The critical aspect of AM parts is the sensitivity to surface anomalies due to net-shape surfaces, i.e surface microcracks and protrusions, localized stresses caused by coarse surface roughness, or sub-surface features placed below the outer skin in the contour region. To reduce the surface roughness and increase the fatigue properties, proper post-process treatments can be applied. This work investigates the improvement in surface quality and fatigue properties due to the electro-chemical milling process of Hirtisation® compared with net-shape condition, on samples manufactured in Ti6Al4V by laser-powder bed fusion (PBF-LB). Post-processing led to a reduction of surface roughness due to the removal of the peaks and sharp valleys that act as crack initiation sites during fatigue tests, but it exposed the sub-skin contouring defects to the free surface. These were the crack initiation sites resulting in a limited improvement of the potential benefits produced by Hirtisation®. This was confirmed by fatigue life predictions based on propagation of surface features and contouring anomalies.

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引用次数: 0

Field test on performance failure of vibration reduction fasteners in metro rail corrugation section

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-14 DOI: 10.1016/j.engfailanal.2025.109408

Chuanqing Dai , Tao Xin , Sen Wang , Yi Yang , Chao Kong , Yaoxuan Fang

The shear-type vibration-damping fastener (SVF) is widely recognized for the superior vibration-reduction effect. However, in a certain city’s metro lines, despite the use of SVF, environmental vibration issues have significantly impacted nearby residents as the operational years have increased. Field investigations revealed a severe rail corrugation phenomenon in the vibration-sensitive section, which may be a potential cause of the suboptimal vibration-damping performance of the SVF. To study this issue, a typical section with severe rail corrugation was selected for on-site testing research. The impact of replacing the SVF with compression-type vibration-damping fasteners (CVF) and subsequent rail grinding on the vibration time–frequency characteristics and noise was analysed. Results indicate that the typical wavelength of rail corrugation of 55–60 mm generated after long-term operation of the SVF track system is associated with wheel-rail system resonance within the frequency of 300.9–328.3 Hz. After replacing the SVF with CVF, the rail vibration acceleration intensity decreased by 36.3 %, and the rail vibration amplitude in the dominant frequencies range of 300–350 Hz significantly reduced, demonstrating a certain degree of control over rail corrugation. Following the rail grinding, the rail dominant frequencies shifted to higher band, the vibration source strength of the tunnel wall decreased by 2 dB, and the noise level within the tunnel was significantly reduced, with the A-weighted maximum sound pressure level decreasing by 12.4 dB(A). The findings provide theoretical references for analysing the failure causes of vibration-damping fastener performance in metro systems and offer potential solutions.

{"title":"Field test on performance failure of vibration reduction fasteners in metro rail corrugation section","authors":"Chuanqing Dai , Tao Xin , Sen Wang , Yi Yang , Chao Kong , Yaoxuan Fang","doi":"10.1016/j.engfailanal.2025.109408","DOIUrl":"10.1016/j.engfailanal.2025.109408","url":null,"abstract":"<div><div>The shear-type vibration-damping fastener (SVF) is widely recognized for the superior vibration-reduction effect. However, in a certain city’s metro lines, despite the use of SVF, environmental vibration issues have significantly impacted nearby residents as the operational years have increased. Field investigations revealed a severe rail corrugation phenomenon in the vibration-sensitive section, which may be a potential cause of the suboptimal vibration-damping performance of the SVF. To study this issue, a typical section with severe rail corrugation was selected for on-site testing research. The impact of replacing the SVF with compression-type vibration-damping fasteners (CVF) and subsequent rail grinding on the vibration time–frequency characteristics and noise was analysed. Results indicate that the typical wavelength of rail corrugation of 55–60 mm generated after long-term operation of the SVF track system is associated with wheel-rail system resonance within the frequency of 300.9–328.3 Hz. After replacing the SVF with CVF, the rail vibration acceleration intensity decreased by 36.3 %, and the rail vibration amplitude in the dominant frequencies range of 300–350 Hz significantly reduced, demonstrating a certain degree of control over rail corrugation. Following the rail grinding, the rail dominant frequencies shifted to higher band, the vibration source strength of the tunnel wall decreased by 2 dB, and the noise level within the tunnel was significantly reduced, with the A-weighted maximum sound pressure level decreasing by 12.4 dB(A). The findings provide theoretical references for analysing the failure causes of vibration-damping fastener performance in metro systems and offer potential solutions.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"173 ","pages":"Article 109408"},"PeriodicalIF":4.4,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Addressing and mitigating risks of failures in metals additive manufacturing concerning the maritime industry

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-13 DOI: 10.1016/j.engfailanal.2025.109398

Mario Augusto Lopes de Castro , Adam Saxty , Martyn Wright , Sean Murray

Additive manufacturing (AM) arises as a promise to increase design freedom and hence to optimize equipment, as this uncages the manufacturing of more complex geometric shapes. Metal AM in the maritime industry is a process in early stages of development so caution- and consciousness are required when designing and reviewing processes (DRPs) are performed, since technological gaps represent a high risk for equipment structural resistance and life. Presented work researched some of most important technological gaps and failures within metals AM, lessons learned from past novel technologies, the environment in which the maritime industry is enclosed and respective common practices, concluding that dichotomy − decisions framed as binary choices of approval or rejection −, fixed mindsets − a belief that abilities and characteristics are static and unchangeable − and dependence of immature standards, guidelines and regulations represents a risk in terms of high potential of omissions. One of the challenges within mentioned ecosystem consists in improving internal processes and mindsets, both presenting necessary requirements to ensure safety of well-established technologies but also headlining gaps when under development ones are assessed. This publication suggests that the use of the new herein developed Cross-Hybrid Evaluations (CHP) in DRPs represents a significant leap towards safety insurance, increasing of reliability and reduction of barriers that hinders the plenty expansion of metal AM within maritime industry.

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引用次数: 0

Analysis of wear resistance deterioration at elevated temperature of medium carbon alloy steel treated by composite strengthening method of nitriding and microshot peening

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-13 DOI: 10.1016/j.engfailanal.2025.109416

Huaiyu Huang , Kaipeng Liang , Bin Cui , Guanghong Wang , Wei Zou , Zhi Zhang , Xinshuo Li , Rui Chen , Qi Liu , Han Wu , Guodong Huang , Qingsong Huang

The influence of high temperature on wear resistance deterioration of 38CrMoAl alloy steel treated by a composite strengthening method of nitriding followed by microshot peening was investigated, compared with that of singly nitrided steel. Results show that the tribological performance of the compositely strengthened steel is better than that of singly nitrided steel, regardless of the normal load and the temperature. The improvement was attributed to the increased surface hardness, residual compressive stress and reduced roughness. Notably, the wear loss of the compositely strengthened steel remarkably increased at the high temperature and heavy load. Deterioration of the excellent wear resistance of the compositely strengthened steel was resulted from the combined effects of significant residual stress release and redistribution, as well as the growth of surface grains and the decrease of hardness at elevated temperature, which suggests that the compositely strengthened steel is more effective to be used at room temperature. Wear mechanism of the compositely strengthened steel is primarily abrasive wear, except for fatigue pitting at room temperature.

{"title":"Analysis of wear resistance deterioration at elevated temperature of medium carbon alloy steel treated by composite strengthening method of nitriding and microshot peening","authors":"Huaiyu Huang , Kaipeng Liang , Bin Cui , Guanghong Wang , Wei Zou , Zhi Zhang , Xinshuo Li , Rui Chen , Qi Liu , Han Wu , Guodong Huang , Qingsong Huang","doi":"10.1016/j.engfailanal.2025.109416","DOIUrl":"10.1016/j.engfailanal.2025.109416","url":null,"abstract":"<div><div>The influence of high temperature on wear resistance deterioration of 38CrMoAl alloy steel treated by a composite strengthening method of nitriding followed by microshot peening was investigated, compared with that of singly nitrided steel. Results show that the tribological performance of the compositely strengthened steel is better than that of singly nitrided steel, regardless of the normal load and the temperature. The improvement was attributed to the increased surface hardness, residual compressive stress and reduced roughness. Notably, the wear loss of the compositely strengthened steel remarkably increased at the high temperature and heavy load. Deterioration of the excellent wear resistance of the compositely strengthened steel was resulted from the combined effects of significant residual stress release and redistribution, as well as the growth of surface grains and the decrease of hardness at elevated temperature, which suggests that the compositely strengthened steel is more effective to be used at room temperature. Wear mechanism of the compositely strengthened steel is primarily abrasive wear, except for fatigue pitting at room temperature.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"171 ","pages":"Article 109416"},"PeriodicalIF":4.4,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The formation mechanism of flaw detection in wind power gear steel

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-13 DOI: 10.1016/j.engfailanal.2025.109417

Yuntian Zhang , Guoguang Cheng , Wenjun Shen , Tao Zhang , Jie Yu , Shijian Li

In order to address the frequent occurrence of ultrasonic testing defects in wind power gear steel, this paper investigates the causes of these defects. Through defect observation and comprehensive sampling analysis of the refining process, the types of defects and their stages of formation have been clarified. Coupled with thermodynamic calculations, the formation mechanism of defect inclusions was determined, and process improvement measures were proposed. The results indicate that the main cause of the testing defects is large-sized inclusions, which typically exceed 400 μm in size. These large-sized inclusions are formed by the aggregation of micron-sized liquid inclusions of CaO-MgO-Al₂O₃-SiO₂. This type of inclusion originates from the high SiO₂ content of CaO-MgO-Al₂O₃-SiO₂ inclusions produced during the VD process. Analysis reveals that the excessively low [Al] content in the molten steel during the VD process is the fundamental reason for the formation of high SiO₂ content CaO-MgO-Al₂O₃-SiO₂ inclusions. Due to the low [Al] content, the [Si] in the molten steel reduces (Al₂O₃) in inclusions, resulting in high SiO₂ content CaO-MgO-Al₂O₃-SiO₂ inclusions. As the [Al] content in the molten steel increases again, the SiO₂ in the inclusions is partially reduced; however, high SiO₂ content CaO-MgO-Al₂O₃-SiO₂ inclusions still remain. Increasing the [Al] content in the molten steel during the VD process to 0.01 % − 0.014 % can effectively prevent the entry of [Si] into the inclusions when the [Al] content is too low, and it can also reduce the high [Ca] effect on the molten steel caused by slag-steel balance when the [Al] content is excessively high. This is a reasonable measure to reduce the occurrence of high SiO₂ content CaO-MgO-Al₂O₃-SiO₂ inclusions.

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引用次数: 0

Stress corrosion crack initiation and propagation characteristics of 7xxx high-strength Al alloy plate: Experiments and modeling

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-12 DOI: 10.1016/j.engfailanal.2025.109412

Yue Hou , Shougang Chen , Zihao Guo , Yanan Pu , Wen Li , Huimeng Feng , Shushuai Liu

High-strength 7xxx aluminum (Al) alloy is widely used in aerospace and ocean engineering as a structural material, causing a risk of stress corrosion crack (SCC) in equipment. Mechanical experiments equipped with in-situ electrochemical measurements and finite element modeling were conducted on 7xxx Al alloy in 3.5 wt% NaCl solution to research the effect of elastic–plastic deformation on SCC mechanism. The grain structure, corrosion pits, surface cracks and electrochemical behavior of the SCC samples were compared. A model for pit-crack transformation was proposed that considered the combined effects of constant load and slow strain rate tensile. Findings demonstrated that the stress induced a variation in the microstructure of the 7xxx Al alloy, which indicated an increase in the proportion of low angle grain boundaries (LAGBs) and a rise in the kernel average misorientation (KAM) value. The strain concentration coefficient (

K_{ε}

) of the plastic deformation sample was higher than that of the elastic deformation sample, due to the larger aspect ratio (width D/depth d) of its pits. The severe plastic deformation sample (ε_s = 12.5 %) had the highest SCC susceptibility, exhibiting large-scale and dense SCC crack generation due to microstructure transformation and passive film defects.

{"title":"Stress corrosion crack initiation and propagation characteristics of 7xxx high-strength Al alloy plate: Experiments and modeling","authors":"Yue Hou , Shougang Chen , Zihao Guo , Yanan Pu , Wen Li , Huimeng Feng , Shushuai Liu","doi":"10.1016/j.engfailanal.2025.109412","DOIUrl":"10.1016/j.engfailanal.2025.109412","url":null,"abstract":"<div><div>High-strength 7xxx aluminum (Al) alloy is widely used in aerospace and ocean engineering as a structural material, causing a risk of stress corrosion crack (SCC) in equipment. Mechanical experiments equipped with in-situ electrochemical measurements and finite element modeling were conducted on 7xxx Al alloy in 3.5 wt% NaCl solution to research the effect of elastic–plastic deformation on SCC mechanism. The grain structure, corrosion pits, surface cracks and electrochemical behavior of the SCC samples were compared. A model for pit-crack transformation was proposed that considered the combined effects of constant load and slow strain rate tensile. Findings demonstrated that the stress induced a variation in the microstructure of the 7xxx Al alloy, which indicated an increase in the proportion of low angle grain boundaries (LAGBs) and a rise in the kernel average misorientation (KAM) value. The strain concentration coefficient (<span><math><msub><mi>K</mi><mi>ε</mi></msub></math></span>) of the plastic deformation sample was higher than that of the elastic deformation sample, due to the larger aspect ratio (width <em>D</em>/depth <em>d</em>) of its pits. The severe plastic deformation sample (<em>ε</em><sub>s</sub> = 12.5 %) had the highest SCC susceptibility, exhibiting large-scale and dense SCC crack generation due to microstructure transformation and passive film defects.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"172 ","pages":"Article 109412"},"PeriodicalIF":4.4,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigating the effects of the moisture content of filling and shear rate on the shear characteristics of rock-like materials with joint

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-12 DOI: 10.1016/j.engfailanal.2025.109411

Yunjin Hu, Chenxing Tian, Caijun Shao, Yong Niu

Rock joints in fault zones are commonly filled with fault gouge, where clay fillings are common. Until now, the shear characteristics of filled rock joints under different moisture contents and shear rates have not been well understood. This work investigates the mechanical behaviour of rock-like materials with clay-filled joints under compression-shear loading. A self-developed rock shear test system was used to conduct direct shear tests on rock-like materials under three normal stresses and five shear rates. Six types of natural red clay with different moisture contents were selected for filling. The coupling effects of the moisture content and shear rate on the mechanical properties of rock-like samples with clay-filled joints were investigated. Furthermore, the failure characteristics of the failure surfaces of rock-like materials after shearing were scanned via 3D scanning. The test results show that the moisture content of fillings and shear rate significantly affect the shear characteristics of rock-like materials with filled joints. The plastic limit moisture content is a critical point where the shear rate has the least effect on the shear strength. Under dry soil filling conditions, the degree of shear damage on the shear plane is the smallest. The present results can provide guidance for slope protection projects.

{"title":"Investigating the effects of the moisture content of filling and shear rate on the shear characteristics of rock-like materials with joint","authors":"Yunjin Hu, Chenxing Tian, Caijun Shao, Yong Niu","doi":"10.1016/j.engfailanal.2025.109411","DOIUrl":"10.1016/j.engfailanal.2025.109411","url":null,"abstract":"<div><div>Rock joints in fault zones are commonly filled with fault gouge, where clay fillings are common. Until now, the shear characteristics of filled rock joints under different moisture contents and shear rates have not been well understood. This work investigates the mechanical behaviour of rock-like materials with clay-filled joints under compression-shear loading. A self-developed rock shear test system was used to conduct direct shear tests on rock-like materials under three normal stresses and five shear rates. Six types of natural red clay with different moisture contents were selected for filling. The coupling effects of the moisture content and shear rate on the mechanical properties of rock-like samples with clay-filled joints were investigated. Furthermore, the failure characteristics of the failure surfaces of rock-like materials after shearing were scanned via 3D scanning. The test results show that the moisture content of fillings and shear rate significantly affect the shear characteristics of rock-like materials with filled joints. The plastic limit moisture content is a critical point where the shear rate has the least effect on the shear strength. Under dry soil filling conditions, the degree of shear damage on the shear plane is the smallest. The present results can provide guidance for slope protection projects.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"171 ","pages":"Article 109411"},"PeriodicalIF":4.4,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Moderate temperature wear behaviour of Magnesium-Dicalcium silicate composite

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-12 DOI: 10.1016/j.engfailanal.2025.109413

P. Kumaravelu, S. Arulvel, Jayakrishna Kandasamy, P. Jeyapandirajan

This study investigates the effect of dicalcium silicate content on the moderate-temperature wear behaviour of magnesium-dicalcium silicate (AZ91D-Ca₂SiO₄) composites over a temperature range of 100 °C,150 °C, 200 °C and 250 °C. Various wear mechanisms were investigated in AZ91D-Ca₂SiO₄ composites under specific temperature conditions. AZ91D-Ca₂SiO₄ composites were fabricated with different weight percentages (2.5 %, 5 %, and 10 %) of Ca₂SiO₄ reinforcement using the stir casting process. Hardness, phase composition, wear depth, and morphological changes were observed in the composites after wear testing. The metal-oxide interaction regimes were precisely detailed through the tribology characterization. The results demonstrate a significant increase in wear rate as temperatures rise from 100 °C to 250 °C. Specifically, at temperatures around 100 °C and 150 °C, abrasive wear and oxidation were identified as the primary wear mechanisms. At moderate temperatures, around 250 °C, abrasive wear, plastic deformation, and delamination were the dominant wear mechanisms. The higher presence of Mg-Si and Mg-Ca phases, along with Ca₂SiO₄ particles, on the worn surfaces of the composites has reduced the oxidation of the AZ91D matrix at moderate temperatures. Furthermore, this study reports a detailed investigation into the influence of different weight percentages (2.5 %, 5 %, and 10 %) of Ca₂SiO₄ on the moderate-temperature wear behaviour of AZ91D and AZ91D-Ca₂SiO₄ composites.

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引用次数: 0

Establishment of theoretical model and dynamic analysis of gear meshing force for the multi-gear driving system considering the effect of friction

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-11 DOI: 10.1016/j.engfailanal.2025.109382

He Bu, Jie Li, Jingbo Guo, Zhuyu Gao, Yuhang Zhao

The coupling effect occurs in the force transmission between the pinions and the large gear ring in the multi-gear driving system. This interaction can easily lead to impacts and vibrations, resulting in wear and failure of the gear teeth, thereby threatening the operational safety of the entire gear system. In this paper, a theoretical model of meshing force of a multi-gear driving system considering friction is established based on the centralized parameter method, and a method to analyze the wear failure of gear teeth is proposed. Taking the shield machine main bearing multi-gear driving system as an example, the theoretical calculation of the time-varying meshing stiffness of the internal gears is carried out first. The theoretical value of the meshing force is calculated, and the relative error between it and the simulation value is calculated to be 2.95% by combining with the transient dynamics analysis. While the comparison verifies the correctness of the theoretical model of the proposed meshing force, the control threshold of the dynamic meshing force of the large gear ring is finally obtained as

2.39 \times 1 0^{5}

N. The study shows that multiple drive units can lead to the coupling effect of the force on the large gear ring, and its service time is the key to determining the span of the system. An increase in the friction factor of the tooth surface will lead to shock and vibration in gear meshing, which will increase the wear of the gear teeth. Ensuring that the value of the meshing force is within the control threshold can make the drive system more stable. The method proposed in this study will guide the design, manufacture, and installation of multi-gear driving systems. It provides novel research insights and theoretical support for effectively preventing gear wear failure and has important engineering significance.

{"title":"Establishment of theoretical model and dynamic analysis of gear meshing force for the multi-gear driving system considering the effect of friction","authors":"He Bu, Jie Li, Jingbo Guo, Zhuyu Gao, Yuhang Zhao","doi":"10.1016/j.engfailanal.2025.109382","DOIUrl":"10.1016/j.engfailanal.2025.109382","url":null,"abstract":"<div><div>The coupling effect occurs in the force transmission between the pinions and the large gear ring in the multi-gear driving system. This interaction can easily lead to impacts and vibrations, resulting in wear and failure of the gear teeth, thereby threatening the operational safety of the entire gear system. In this paper, a theoretical model of meshing force of a multi-gear driving system considering friction is established based on the centralized parameter method, and a method to analyze the wear failure of gear teeth is proposed. Taking the shield machine main bearing multi-gear driving system as an example, the theoretical calculation of the time-varying meshing stiffness of the internal gears is carried out first. The theoretical value of the meshing force is calculated, and the relative error between it and the simulation value is calculated to be 2.95% by combining with the transient dynamics analysis. While the comparison verifies the correctness of the theoretical model of the proposed meshing force, the control threshold of the dynamic meshing force of the large gear ring is finally obtained as <span><math><mrow><mn>2</mn><mo>.</mo><mn>39</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>5</mn></mrow></msup></mrow></math></span> N. The study shows that multiple drive units can lead to the coupling effect of the force on the large gear ring, and its service time is the key to determining the span of the system. An increase in the friction factor of the tooth surface will lead to shock and vibration in gear meshing, which will increase the wear of the gear teeth. Ensuring that the value of the meshing force is within the control threshold can make the drive system more stable. The method proposed in this study will guide the design, manufacture, and installation of multi-gear driving systems. It provides novel research insights and theoretical support for effectively preventing gear wear failure and has important engineering significance.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"171 ","pages":"Article 109382"},"PeriodicalIF":4.4,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fracture mechanism analysis and life-prolonging investigation of butt weld for ladle crane

IF 4.4 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2025-02-10 DOI: 10.1016/j.engfailanal.2025.109389

Yuhui Guo, Gang Rao, Zhang Dang, Ruyi Zhang, Huixin Luo, Rui Yuan

The butt weld between the T-shaped steel and the main web of ladle crane is a crucial weld to bear the lifting load. Since it is mainly considered to be subjected to compressive stress, this weld is generally not regarded as the key area of fatigue assessment. An obvious crack was found in the butt weld of an in-service ladle crane during a routine inspection. In this paper, the cracking mechanism and life-prolonging scheme were studied by means of field tests and numerical analysis. Firstly, the stress history signal according to the cracked area were acquired with several working cycles. It was concluded that the unconventionally imagined tensile and compressive stress are generated during the running process of the crane, which further led to several high-level stress cycles in a typical working cycle. A Finite Element Model (FEM) of the bridge containing a fine solid mesh of the studied weld was established by using sub-model technology. Combined with the rain flow counting results of the measured stresses and the Equivalent Structural Stress (ESS) solving technique based on the FEM, the ESS spectrum of the cracked area was proposed. The fatigue life of the cracked local area is analyzed based on the stress spectrum and the failure mechanism of the butt weld is revealed. A life-prolonging scheme for the cracked local structure was proposed and the fatigue life of the butt-weld area after reinforcement is predicted by using the ESS spectrum, which verifies the effectiveness of reinforcement. Up to now, the ladle crane has been operating normally for nearly 4 years, no new cracks have appeared in the originally cracked are, providing the effectiveness of the life-prolonging scheme.

{"title":"Fracture mechanism analysis and life-prolonging investigation of butt weld for ladle crane","authors":"Yuhui Guo, Gang Rao, Zhang Dang, Ruyi Zhang, Huixin Luo, Rui Yuan","doi":"10.1016/j.engfailanal.2025.109389","DOIUrl":"10.1016/j.engfailanal.2025.109389","url":null,"abstract":"<div><div>The butt weld between the T-shaped steel and the main web of ladle crane is a crucial weld to bear the lifting load. Since it is mainly considered to be subjected to compressive stress, this weld is generally not regarded as the key area of fatigue assessment. An obvious crack was found in the butt weld of an in-service ladle crane during a routine inspection. In this paper, the cracking mechanism and life-prolonging scheme were studied by means of field tests and numerical analysis. Firstly, the stress history signal according to the cracked area were acquired with several working cycles. It was concluded that the unconventionally imagined tensile and compressive stress are generated during the running process of the crane, which further led to several high-level stress cycles in a typical working cycle. A Finite Element Model (FEM) of the bridge containing a fine solid mesh of the studied weld was established by using sub-model technology. Combined with the rain flow counting results of the measured stresses and the Equivalent Structural Stress (ESS) solving technique based on the FEM, the ESS spectrum of the cracked area was proposed. The fatigue life of the cracked local area is analyzed based on the stress spectrum and the failure mechanism of the butt weld is revealed. A life-prolonging scheme for the cracked local structure was proposed and the fatigue life of the butt-weld area after reinforcement is predicted by using the ESS spectrum, which verifies the effectiveness of reinforcement. Up to now, the ladle crane has been operating normally for nearly 4 years, no new cracks have appeared in the originally cracked are, providing the effectiveness of the life-prolonging scheme.</div></div>","PeriodicalId":11677,"journal":{"name":"Engineering Failure Analysis","volume":"172 ","pages":"Article 109389"},"PeriodicalIF":4.4,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0