Study on Mechanical Behavior of Tensile Armor Wires of Marine Flexible Pipes and Cables During Winding Process

2019 ◽  
Author(s):  
Qingzhen Lu ◽  
Shanghua Wu ◽  
Dong Wang ◽  
Zhixun Yang ◽  
Yuanchao Yin ◽  
...  
Keyword(s):  
Residual Stress ◽  
Cross Section ◽  
Mechanical Model ◽  
Internal Force ◽  
Tension Force ◽  
Flexible Pipes ◽  
Minimum Residual ◽  
Wire Cross Section ◽  
Winding Tension ◽  
The Relationship

Abstract In this paper, a mechanical model of armor wire winding process is established to quantify the relationship between the tension force and the internal force of armor wire cross section in winding process. Then based on this model, a method for predicting the residual stress of armor wire cross section after winding is presented. The reasonable winding tension force and the minimum residual stress are discussed. In addition, the reasonable design of the processing equipment is further discussed. This paper provides a useful reference for the evaluation of key parameters and the prediction of residual stress in the processing of tensile armor layer of offshore flexible pipes and cables.

Fracture Behavior of a Brittle Coating on an Elastic Substrate under Residual Stress

2011 ◽  
Vol 217-218 ◽  
pp. 595-599
Author(s):  
Ban Quan Yang ◽  
Peng Li
Keyword(s):  
Residual Stress ◽  
Shear Stress ◽  
Tensile Stress ◽  
Mechanical Model ◽  
Fracture Behavior ◽  
Crack Density ◽  
Elastic Substrate ◽  
Brittle Coating ◽  
Distribution Laws ◽  
The Relationship

The fracture behavior of a brittle coating on an elastic substrate under residual stress is investigated. Using a mechanical model, the analytical solutions for the distribution laws of the tensile stress developed in the coating, the shear stress developed along the interface and the relationship between the crack density of the coating and the residual stress can be obtained. The analytic relationship between the crack density and the residual stress can also be taken as a new expression to estimate the magnitude of the residual stress. A numerical example is presented to show how the crack density varies versus the residual stress.

scholarly journals Exploring the relationship between spiritual well-being and death anxiety in patients with gynecological cancer: a cross-section study

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Yue Feng ◽  
Xingcan Liu ◽  
Tangwei Lin ◽  
Biru Luo ◽  
Qianqian Mou ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Cross Section ◽  
Death Anxiety ◽  
Religious Beliefs ◽  
Gynecological Cancer ◽  
Well Being ◽  
Life Questionnaire ◽  
Section Study ◽  
Spiritual Well Being ◽  
The Relationship

Abstract Background In recent years, spiritual well-being has gradually gained the attention of health care providers in China, especially those in oncology departments, who have recognized the importance of improving spiritual well-being in cancer patients. Since most of the current research on spiritual well-being has been carried out in areas with religious beliefs, this study was conducted in the context of no development of formal religion. The purpose of this study was to explore the relationship between death anxiety and spiritual well-being and the related factors of spiritual well-being among gynecological cancer patients. Methods This cross-section study was conducted among 586 gynecological cancer patients. The European Organization for Research and Treatment for Cancer Quality of Life Questionnaire-spiritual well-being32 (EORTC QLQ-SWB32) and Templer's Death Anxiety Scale (T-DAS) were used to measure spiritual well-being and death anxiety. The Multiple Linear Regression Model was used to determine the relationship between spiritual well-being and death anxiety. Results For all participants, the highest QLQ-SWB32 centesimal score was 75.13 on the Relationship with Other scale, and the lowest was 60.33 on the Relationship with Someone or Something Greater Scale. The mean Death Anxiety score was 5.31 (SD 3.18). We found that Relationship with Someone or Something Greater was the only scale not associated with death anxiety. Overall, patients with lower death anxiety have a higher level of spiritual well-being. Besides, a high Relationship with Other score was associated with living with a partner (B = 2.471, P < 0.001) and married (B = -6.475, P = 0.001). Patients with higher Global-SWB were retired (B = 0.387, P = 0.019). Conclusions Our study found that the spiritual well-being of patients with gynecological cancer in China was no worse than in other countries with religious beliefs and patients with lower death anxiety have a higher level of spiritual well-being. Clinical staff should pay attention to the spiritual health of cancer patients, and spiritual care should be regarded as an essential element in cancer care.

scholarly journals Influence of Preaging Temperature on the Indentation Strength of 3Y-TZP Aged in Ambient Atmosphere

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2767
Author(s):  
Ki-Won Jeong ◽  
Jung-Suk Han ◽  
Gi-Uk Yang ◽  
Dae-Joon Kim
Keyword(s):  
Residual Stress ◽  
Phase Transformation ◽  
Low Temperature ◽  
Compressive Residual Stress ◽  
Yttria Stabilized Zirconia ◽  
Ambient Atmosphere ◽  
Aged Specimen ◽  
Stabilized Zirconia ◽  
M Phase ◽  
The Relationship

Yttria-stabilized zirconia (3Y-TZP) containing 0.25% Al2O3, which is resistant to low temperature degradation (LTD), was aged for 10 h at 130–220 °C in air. The aged specimens were subsequently indented at loads ranging from 9.8 to 490 N using a Vickers indenter. The influence of preaging temperature on the biaxial strength of the specimens was investigated to elucidate the relationship between the extent of LTD and the strength of zirconia restorations that underwent LTD. The indented strength of the specimens increased as the preaging temperature was increased higher than 160 °C, which was accompanied by extensive t-ZrO2 (t) to m-ZrO2 (m) and c-ZrO2 (c) to r-ZrO2 (r) phase transformations. The influence of preaging temperature on the indented strength was rationalized by the residual stresses raised by the t→m transformation and the reversal of tensile residual stress on the aged specimen surface due to the indentation. The results suggested that the longevity of restorations would not be deteriorated if the aged restorations retain compressive residual stress on the surface, which corresponds to the extent of t→m phase transformation less than 52% in ambient environment.

Numerical Simulation on Velocity Profiles of Mill Bearing Lubrication

2010 ◽  
Vol 145 ◽  
pp. 282-286
Author(s):  
Qing Xue Huang ◽  
Jian Mei Wang ◽  
Yu Gui Li ◽  
Li Feng Ma ◽  
Chun Jiang Zhao
Keyword(s):  
Cross Section ◽  
Velocity Profiles ◽  
Flow State ◽  
Oil Film ◽  
Velocity Gradients ◽  
Oil Flow ◽  
The Mathematical Model ◽  
The Relationship ◽  
General Velocity ◽  
Oil Film Pressure

No 460 oil-film bearing oil as the dedicated lubricant is regarded as the incompressible Newtonian fluid. To comprehensively analyze the real oil flow state, the mathematical model on velocity profiles, together with its dimensionless equations, is established, and the calculating program is developed to simulate the 3D velocity profiles and velocity gradients at different oil flow layers. The relationship between velocity profiles and the oil film pressure is discussed, and the velocity tendency is consistent with the general velocity profile of wedge cross section. The conclusions are beneficial to the further study on lubricating performances of heavy contact components and to prolong their service lives.

Optimization Analysis of the Wedge Block Surface of NYD Contact Backstop

2013 ◽  
Vol 433-435 ◽  
pp. 2277-2281
Author(s):  
Quan Wei Wang ◽  
Ming Hui Wang ◽  
Dong Li ◽  
Dian Mao Wan ◽  
Rong Meng
Keyword(s):  
Cross Section ◽  
Design Parameters ◽  
Optimization Analysis ◽  
Archimedes Spiral ◽  
The Cross ◽  
Section Curve ◽  
Relationship Of ◽  
The Relationship

By analyzing the relationship of the design parameters of NYD contact backstop, the cross-section curve of the wedge block has been discussed as Archimedes spiral, logarithm spiral and arc. Each curve is designed optimally using MATLAB optimization toolbox. The merits and drawbacks of each curve are discussed.

Numerical Simulation of the Effects of Preheating on Electron Beam Additive Manufactured Ti-6Al-4V Build Plate

2016 ◽  
Vol 879 ◽  
pp. 274-278 ◽  
Author(s):  
Jun Cao ◽  
Philip Nash
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Finite Element ◽  
Electron Beam ◽  
Cross Section ◽  
Element Model ◽  
Normal Direction ◽  
Thermal Residual Stresses ◽  
Longitudinal Residual Stress ◽  
Middle Cross Section

In an earlier study, a 3-D thermomechanical coupled finite element model was built and experimentally validated to investigate the evolution of the thermal residual stresses and distortions in electron beam additive manufactured Ti-6Al-4V build plates. In this study, an investigation using this robust and accurate model was focused on an efficient preheating method, in which the electron beam quickly scanned across the substrate to preheat the build plate prior to the deposition. Various preheat times, beam powers, scan rates, scanning paths and cooling times (between the end of current preheat scan/deposition layer and the beginning of the next preheat scan/deposition layer) were examined, and the maximum distortion along the centerline of the substrate and the maximum longitudinal residual stress along the normal direction on the middle cross-section of the build plate were quantitatively compared. The results show that increasing preheat times and beam powers could effectively reduce both distortion and residual stress for multiple layers/passes components.

The Materials Science of “Permeable Polysilicon” Thin Films

2001 ◽  
Vol 687 ◽  
Author(s):  
George M Dougherty ◽  
Timothy Sands ◽  
Albert P. Pisano
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Materials Science ◽  
Single Step ◽  
Process Window ◽  
Silicon Thin Films ◽  
Growth Regime ◽  
Deposition Parameters ◽  
Simple Kinetic Model ◽  
The Relationship

AbstractPolycrystalline silicon thin films that are permeable to fluids, known as permeable polysilicon, have been reported by several researchers. Such films have great potential for the fabrication of difficult to make MEMS structures, but their use has been hampered by poor process repeatability and a lack of physical understanding of the origin of film permeability and how to control it. We have completed a methodical study of the relationship between process, microstructure, and properties for permeable polysilicon thin films. As a result, we have determined that the film permeability is caused by the presence of nanoscale pores, ranging from 10-50 nm in size, that form spontaneously during LPCVD deposition within a narrow process window. The unusual microstructure within this process window corresponds to the transition between a semicrystalline growth regime, exhibiting tensile residual stress, and a columnar growth regime exhibiting compressive residual stress. A simple kinetic model is proposed to explain the unusual morphology within this transition regime. It is determined that measurements of the film residual stress can be used to tune the deposition parameters to repeatably produce permeable films for applications. The result is a convenient, single-step process that enables the elegant fabrication of many previously challenging structures.

Experimental Research on the Relationship between Surface Polishing and Fracture Strength for Ground Ceramics

2013 ◽  
Vol 770 ◽  
pp. 433-436
Author(s):  
Xin Li Tian ◽  
Jian Quan Wang ◽  
Bao Guo Zhang ◽  
Peng Xiao Wang
Keyword(s):  
Residual Stress ◽  
Fracture Strength ◽  
Ground Surface ◽  
Residual Tensile Stress ◽  
Residual Stress Field ◽  
Polishing Process ◽  
Machined Surface ◽  
X Ray ◽  
Surface Polishing ◽  
The Relationship

Fracture strength is one of the key mechanics performances for engineering ceramics products, greatly influenced by the microscopic topography and residual stress field of ground surface. In this work, several testing equipments, such as the metallurgical microscope, surface profiler and X ray residual stress tester were introduced to investigate the relationships between microscopic topography, surface roughness, residual stress and fracture strength of ground ceramics, after the surface grinding and mechanical polishing. The experimental results show that a smoother machined surface with low roughness and residual stress is obtained through polishing with absolute alcohol for 20 minutes; the fracture strength of Si3N4SiC and Al2O3 are increased by 6.64%8.18% and 6.58% respectively, comparing to the ceramics without polishing; the surface stress concentration and residual tensile stress of polished ceramics are both reduced after an appropriate time of polishing process, which causes a certain improvement of ground fracture strength.

Structural Analysis and Internal Force Calculation of Variable Cross-Section Silo

2012 ◽  
Vol 446-449 ◽  
pp. 429-434
Author(s):  
Rui Ting Ma
Keyword(s):  
Cross Section ◽  
Variable Cross Section ◽  
Internal Force ◽  
Variable Cross ◽  
Axially Symmetric ◽  
Internal Forces ◽  
Differential Element ◽  
Symmetric Load ◽  
Force Calculation ◽  
Constant Section

In this paper, the differential element of constant-section silo wall suffering from axially symmetric load is analyzed. From the results of constant-section silo, the author derives the displacements and internal forces of variable cross-section silo. Through a specific example, this paper compares the displacements , internal forces and concrete consumption of variable cross-section silo with those of constant-section silo, and discusses the merits of variable cross-section silo.

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