Dimensional Changes in Tube Swaging

1966 ◽  
Vol 88 (2) ◽  
pp. 147-150 ◽  
Author(s):  
Serope Kalpakjian
Keyword(s):  
Wall Thickness ◽  
Appreciable Effect ◽  
Process Variables ◽  
Workpiece Material ◽  
Thickness Increase ◽  
Dimensional Changes ◽  
Independent Variables ◽  
Rotary Swaging ◽  
Diameter Reduction ◽  
Wall Thickness Increase

The purpose of this study was to investigate changes in the wall thickness of tubes sunk by the rotary swaging process. The independent variables were: Workpiece material, original wall thickness of tube, die angle, die overgrind, and diameter reduction. The results indicated that of these five variables only the diameter reduction was a factor in wall-thickness increase. Material and other process variables did not appear to have appreciable effect within the range studied.

Shell Body Nose Forming by Rotary Swaging Process

2011 ◽  
Vol 213 ◽  
pp. 221-225 ◽  
Author(s):  
Jeong Hwan Jang ◽  
Byeong Don Joo ◽  
Sung Min Mun ◽  
Young Hoon Moon
Keyword(s):  
Finite Element ◽  
Initial Thickness ◽  
Dimensional Changes ◽  
Rotary Swaging ◽  
Inside Diameter ◽  
Before And After ◽  
Forming Characteristics ◽  
Inner Diameter ◽  
The Given ◽  
Diameter Reduction

Studies on the forming characteristics by a rotary swaging process using the sub-scale specimens have been carried out to obtain a shell body nose of desirable quality. To analyze the changes of the nose thickness and length at the respective reduction of inside diameter, the finite element simulations were carried out. As a result, the desired target dimension is satisfied with the diameter reduction of more than 64 % for the given preform. The thickness of nose area increased up to 56.1 % from initial thickness of 2.62 mm to 4.09 mm after swaging. The values of the hardness before and after swaging were 208 HV and 325 HV, respectively. To analyze the dimensional changes (length and thickness) of nose area with decreasing inside diameter, the rotary swaging test was carried out for two different diameter reductions such as 65 % and 67 %. The lengths of nose area for the diameter reductions are 11.79 mm in 65 % and 12.53 mm in 67 %, respectively. At the diameter reduction of more than 67%, the crack occurs when the localized strain hardening reduces ductility in internal area. Therefore, the nose area should be formed from 64% to 67% reduction in target inner diameter.

P189 Use of transabdominal ultrasonography for the evaluation of Crohn’s disease activity

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S233-S233
Author(s):  
E Yorulmaz ◽  
B Yigit ◽  
M S Erturk ◽  
U Erdem ◽  
U Yanc ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Disease Activity ◽  
Flow Velocity ◽  
Wall Thickness ◽  
Transabdominal Ultrasonography ◽  
Thickness Increase ◽  
Sensitivity Level ◽  
Crohn’S Disease Activity ◽  
Wall Thickness Increase

Abstract Background Ileocolonoscopy is accepted as the gold standard method for the diagnosis of Crohn’s disease (CD). However, there are cases where it is inadequate due to being invasive, failure to allow endoscopic exploration of the small intestine, and failure to show the extraintestinal pathologies. In the present study, it is aimed to compare clinical, endoscopic scores and computerised tomography enterography (CTE) findings with transabdominal ultrasonography (TAUS) findings in order to evaluate the activity of CD. Methods The study included 79 patients diagnosed with CD. Crohn’s Disease Activity Index (CDAI) and Harvey Bradshaw Index (HBI) were used for the evaluation of the clinical activities of the patients. The patients with CDAI equal to 150 and more and HBI equal to 5 points and more were assessed as clinically active. Colonoscopic disease activity was assessed by The Simple Endoscopic Score for Crohn’ disease (SES-CD), SES-CD score of 3 and higher was defined as endoscopically active. In the evaluation of CTE and TAUS, the measurement of the thickness of the intestinal wall above 3 mm was accepted as pathological. Abscess, mass, fistula and ileus were evaluated as complications. Superior mesenteric artery (SMA) flow velocity was assessed by Color Doppler US. Limberg score was graded from Grades 0 to 4 for Doppler TAUS. Results Of the patients, 57 (72.1%) were male and 22 (27.8%) were female. Age average of the patients was 37.5 years (17–64) and the mean duration of disease was 48.6 months (0–240 months). Increase in the wall thickness in CTE and TAUS, detection of inflammation and complication in mesenteric fatty planes were found to be highly significant (p ˂ 0.0001). Wall thickness increase sensitivity level of TAUS according to CTE was 82%, specificity level was 97%, sensitivity level of the inflammation finding in mesenteric fatty planes was measured as 80%, and specificity level as 95%. A significant correlation was found between the wall thickness increase in CTE and TAUS and inflammation in mesenteric fatty planes via CDAI, HBI and SES-CD scoring (p ˂ 0.05). In addition, there was a significant relationship between the presence of lymphadenopathy in CTE in active patients according to HBI (p ˂ 0.05). According to the CDAI and SES-CD scores, Doppler flow velocity of SMA was significantly higher in the active group than the inactive group (p ˂ 0.05). CDAI, HBI and SES-CD results were found highly significant via the Limberg Scoring results (p < 0.0001). Conclusion In the current study, it is shown that TAUS is a diagnostic tool as effective as CTE in the evaluation of CD activity. In addition, it is an important finding that the flow velocity of SMA increases as correlated with inflammation via the Doppler feature of TAUS.

Deformation Behavior of Intrusion Bending for Steel Pipes

2003 ◽  
Author(s):  
Tetsuaki Sano ◽  
Hisashi Naoi
Keyword(s):  
Wall Thickness ◽  
Deformation Behavior ◽  
Diameter Ratio ◽  
Radius Ratio ◽  
Outer Diameter ◽  
Thickness Increase ◽  
Steel Pipes ◽  
Bending Radius ◽  
Outside Diameter ◽  
Wall Thickness Increase

We have investigated the intrusion bending for steel pipes for several years. The bending machine consists of three parts. They are called pusher, guide cylinder and gyro. The aim of this investigation is to reveal the effect of size and strength of materials, pushing forces and so on. That we study in this report are as follows: (1) The effect of bending radius ratio on ovality of outer diameter and eccentricity of wall thickness, and (2) the effect of ratio of wall thickness to outer diameter on ovality of outer diameter and eccentricity of wall thickness. The conclusions of this study are summarized as follows. (1) The ovality of outer diameter and the eccentricity of wall thickness increase as the bending radius ratio decreases. (2) The ovality of outer diameter decreases and the eccentricity of wall thickness increase as thickness outside diameter ratio increases.

Influence by Casing Geometric Imperfection on Anti-Collapse Strength with Finite Element Calculation

2012 ◽  
Vol 268-270 ◽  
pp. 1114-1118
Author(s):  
Ji Jun Xue ◽  
Peng Wang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Wall Thickness ◽  
Element Model ◽  
Element Calculation ◽  
Geometric Imperfection ◽  
Thickness Increase ◽  
Collapse Strength ◽  
Wall Thickness Increase ◽  
Better Than

This essay was to build a finite element model to find the influence by oil casing geometric imperfection on anti-collapse strength. Two types of oil casing, Ф177.8×10.36mm/P110 andФ127×9.19mm/ P110, was taken for the calculation, considering the influence on anti-collapse strength by casing with two elements separately, ovality and non-uniformity of wall thickness. The calculation show that the anti-collapse strength of perfect casing perform better than that of imperfect casing. Ovality is an important factor for the anti-collapse strength, and the anti-collapse strength decrease rapidly as the ovality increase. Non-uniformity of wall thickness is the less important factor for anti-collapse strength, and the anti-collapse strength decrease slightly and slowly while the non-uniformity of wall thickness increase.

scholarly journals Anatomical Variation in Planted Kelempayan (Neolamarckia Cadamba, Rubiaceae)

IAWA Journal ◽  
1995 ◽  
Vol 16 (3) ◽  
pp. 227-287 ◽  
Author(s):  
J. Ismail ◽  
M. Z. Jusoh ◽  
Mohd. H. Sahri
Keyword(s):  
Cell Wall ◽  
Analysis Of Variance ◽  
Wall Thickness ◽  
Anatomical Variation ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Lumen Diameter ◽  
Thickness Increase ◽  
Anatomical Properties ◽  
Wall Thickness Increase

Six plantation grown Kelempayan trees [Neolamarckia cadamba (Roxb.) Bosser, syn. Anthocephalus chinensis (Lamk.) A. Rich. ex Walp., Rubiaceae] were sampled along their radii and at five different height levels to evaluate variations of wood anatomical properties. Analysis of variance indicates that between tree differences in all anatomical properties measured were significant. Vessel proportion increases while ray proportion decreases with height, while both fibre diameter and fibre lumen diameter decrease with height. No significant trend was found for fibre length vertically. Cell wall substance and vessel and ray proportion increase from pith to bark, while fibre proportion decreases. Fibre length and fibre wall thickness increase from pith to bark, while fibre diameter and fibre lumen diameter first increase and then decrease. Within-tree variations are more consistent radially than vertically.

scholarly journals A Student’s Guide to the Classification and Operationalization of Variables in the Conceptualization and Design of a Clinical Study: Part 1

2021 ◽  
Vol 43 (2) ◽  
pp. 177-179 ◽  
Author(s):  
Chittaranjan Andrade
Keyword(s):  
Clinical Study ◽  
Significant Relationship ◽  
Research Experience ◽  
Process Variables ◽  
Know How ◽  
Independent Variables ◽  
Cause And Effect ◽  
Confounding Variables ◽  
Dependent Variables ◽  
The Relationship

Students without prior research experience may not know how to conceptualize and design a study. This article explains how an understanding of the classification and operationalization of variables is the key to the process. Variables describe aspects of the sample that is under study; they are so called because they vary in value from subject to subject in the sample. Variables may be independent or dependent. Independent variables influence the value of other variables; dependent variables are influenced in value by other variables. A hypothesis states an expected relationship between variables. A significant relationship between an independent and dependent variable does not prove cause and effect; the relationship may partly or wholly be explained by one or more confounding variables. Variables need to be operationalized; that is, defined in a way that permits their accurate measurement. These and other concepts are explained with the help of clinically relevant examples.

scholarly journals Optimizing Adsorption of 17α-Ethinylestradiol from Water by Magnetic MXene Using Response Surface Methodology and Adsorption Kinetics, Isotherm, and Thermodynamics Studies

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3150
Author(s):  
Mengwei Xu ◽  
Chao Huang ◽  
Jing Lu ◽  
Zihan Wu ◽  
Xianxin Zhu ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Quadratic Model ◽  
Adsorption Efficiency ◽  
Process Variables ◽  
Adsorption Time ◽  
Initial Concentration ◽  
Independent Variables ◽  
The Impact ◽  
Adsorbent Dose

Magnetic MXene composite Fe3O4@Ti3C2 was successfully prepared and employed as 17α-ethinylestradiol (EE2) adsorbent from water solution. The response surface methodology was employed to investigate the interactive effects of adsorption parameters (adsorption time, pH of the solution, initial concentration, and the adsorbent dose) and optimize these parameters for obtaining maximum adsorption efficiency of EE2. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. Optimization of the process variables for maximum adsorption of EE2 by Fe3O4@Ti3C2 was performed using the quadratic model. The model predicted maximum adsorption of 97.08% under the optimum conditions of the independent variables (adsorption time 6.7 h, pH of the solution 6.4, initial EE2 concentration 0.98 mg L−1, and the adsorbent dose 88.9 mg L−1) was very close to the experimental value (95.34%). pH showed the highest level of significance with the percent contribution (63.86%) as compared to other factors. The interactive influences of pH and initial concentration on EE2 adsorption efficiency were significant (p < 0.05). The goodness of fit of the model was checked by the coefficient of determination (R2) between the experimental and predicted values of the response variable. The response surface methodology successfully reflects the impact of various factors and optimized the process variables for EE2 adsorption. The kinetic adsorption data for EE2 fitted well with a pseudo-second-order model, while the equilibrium data followed Langmuir isotherms. Thermodynamic analysis indicated that the adsorption was a spontaneous and endothermic process. Therefore, Fe3O4@Ti3C2 composite present the outstanding capacity to be employed in the remediation of EE2 contaminated wastewaters.

scholarly journals High productivity micro rotary swaging

2018 ◽  
Vol 190 ◽  
pp. 15002 ◽  
Author(s):  
Eric Moumi ◽  
Marius Herrmann ◽  
Christian Schenck ◽  
Bernd Kuhfuss
Keyword(s):  
Material Flow ◽  
Process Variations ◽  
Main Process ◽  
Forming Process ◽  
Workpiece Material ◽  
High Productivity ◽  
Rotary Swaging ◽  
Micro Parts ◽  
Intensive Investigation ◽  
Clamping Device

Rotary swaging is an incremental forming process with two main process variations plunge and infeed rotary swaging. With plunge rotary swaging, the diameter is reduced within a limited section whereas the infeed rotary swaging enables a diameter reduction over the entire workpiece length. The process is now subject to intensive investigation for manufacturing of micro parts. By increasing the process speed, failures occur particularly due to inappropriate material flow. In plunge rotary swaging, the workpiece material can flow radially into the gap between the dies and thus the workpiece quality suffers. In infeed rotary swaging the workpiece material flows against the feeding direction and can provoke bending or braking of the workpiece. Therefore, additional measures to control both the radial and the axial material flow to enable high productivity micro rotary swaging are investigated. The radial material flow during plunge rotary swaging can be controlled by elastic intermediate elements that enable an increase of productivity by factor three. A spring-loaded clamping device that enables an increase of the productivity by factor four can temporarily buffer the axial material flow in infeed rotary swaging against the feeding direction.

scholarly journals Axial and Radial Material Flow Analysis in Infeed Rotary Swaging of Tubes

2018 ◽  
Vol 190 ◽  
pp. 04003 ◽  
Author(s):  
Yang Liu ◽  
Marius Herrmann ◽  
Christian Schenck ◽  
Bernd Kuhfuss
Keyword(s):  
Wall Thickness ◽  
Material Flow ◽  
Flow Direction ◽  
Flow Analysis ◽  
Material Flow Analysis ◽  
Relative Wall Thickness ◽  
Cold Forming ◽  
Rotary Swaging ◽  
Fundamental Insight ◽  
Actual Ratio

In rotary swaging – an incremental cold forming production technique to reduce the diameter of axisymmetric parts – the material flow can be assumed to be predominantly axial and radial. The actual ratio of this axial and radial flow influences the mechanical properties and especially in tube forming the final geometry. It is known that during mandrel free infeed rotary swaging of tubes the wall thickness changes. The change is depending on the process parameters like incremental and cumulated strain. Hence, the ratio of axial and radial material flow changes. Consequently, the analysis of the wall thickness of rotary swaged tubes enables fundamental insight how to control the material flow direction. In this study, the infeed rotary swaging process of steel tubes with different wall thicknesses from 3 mm to 7 mm and rods were investigated with FEM under two feeding velocities. The axial and radial material flow and the resulting geometry were studied by the relative wall thickness. It could be seen that the relative wall thickness was affected by the feeding velocity as well as the initial wall thickness. The findings of the simulation were validated by rotary swaging experiments.

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