Intermediate die profile design for high-precision production of rectangular stainless-steel bars via new tandem drawing process

The present work is introduced and is shown to be a logical extension of work by Chung and Swift, Ray and Berry, et al. The authors introduce the deep drawing process and analyze the stresses due to radial drawing (including friction), bending the sheet, unbending the sheet, and die profile friction. From these stresses, an expression for the total punch load is developed. The authors also describe the experimental work in which determinations are made of the work hardening exponents, the anisotropic coefficients, the friction coefficients, and the total punch load. The paper concludes by comparing the numerical evaluation of the maximum punch load with that determined from experiments.

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A High Precision Quality Inspection System for Steel Bars Based on Machine Vision

Sensors ◽

10.3390/s18082732 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2732 ◽

Cited By ~ 2

Author(s):

Xinman Zhang ◽

Jiayu Zhang ◽

Mei Ma ◽

Zhiqi Chen ◽

Shuangling Yue ◽

...

Keyword(s):

Machine Vision ◽

High Precision ◽

Absolute Error ◽

Detection Methods ◽

Inspection System ◽

Quality Inspection ◽

Construction Site ◽

High Definition ◽

Steel Bar ◽

Steel Bars

Steel bars play an important role in modern construction projects and their quality enormously affects the safety of buildings. It is urgent to detect whether steel bars meet the specifications or not. However, the existing manual detection methods are costly, slow and offer poor precision. In order to solve these problems, a high precision quality inspection system for steel bars based on machine vision is developed. We propose two algorithms: the sub-pixel boundary location method (SPBLM) and fast stitch method (FSM). A total of five sensors, including a CMOS, a level sensor, a proximity switch, a voltage sensor, and a current sensor have been used to detect the device conditions and capture image or video. The device could capture abundant and high-definition images and video taken by a uniform and stable smartphone at the construction site. Then data could be processed in real-time on a smartphone. Furthermore, the detection results, including steel bar diameter, spacing, and quantity would be given by a practical APP. The system has a rather high accuracy (as low as 0.04 mm (absolute error) and 0.002% (relative error) of calculating diameter and spacing; zero error in counting numbers of steel bars) when doing inspection tasks, and three parameters can be detected at the same time. None of these features are available in existing systems and the device and method can be widely used to steel bar quality inspection at the construction site.

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Analysis of the Redundant Deformation Factor in the Axisymmetric Drawing of AISI 304 Stainless Steel Bars through Experimental Techniques

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.3170 ◽

2010 ◽

Vol 638-642 ◽

pp. 3170-3175

Author(s):

Elaine Carballo Siqueira Corrêa ◽

Maria Teresa Paulino Aguilar ◽

Paulo Roberto Cetlin

Keyword(s):

Stainless Steel ◽

Structural Features ◽

304 Stainless Steel ◽

Aisi 304 Stainless Steel ◽

Stress Strain ◽

Aisi 304 ◽

Steel Bars ◽

Deformation Features ◽

Superposition Technique ◽

The Relationship

One of the most significant aspects of the axisymmetric drawing operation is the occurrence of non-homogeneous deformation in the cross section of the metal. This phenomenon is associated with an internal distortion process that takes place in the bar as it flows through the die, leading to the development of higher drawing forces and affecting the subsequent mechanical behavior of the material. An adequate analysis of the process and of the work hardening of the drawn metal, therefore, must involve a detailed study of the deformation features in the forming operation. In the present work, the deformation in the single-pass drawing of AISI 304 stainless steel bars was investigated through the evaluation of the relationship between the redundant deformation factor and the parameter . Two experimetal procedures were employed in the study: the visioplasticity and the stress-strain curves superposition techniques. The first one, previously considered as the method leading to the most realistic solutions to various forming processes, allowed the establishment of an increasing linear relationship between de redundant deformation factor and the parameter . A similar behavior was observed through the stress-strain curves superposition technique. In this case, however, the redundant deformation factor values were lower or higher than those obtained through visioplasticity according to the drawing conditions and more sensitive to variations of the parameter . The results were compared to those exhibited by the AISI 420 stainless steel, revealing the influence of the structural features on the behavior of the metal.

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The Use of Mn-Kα X-Rays and a New Model of PSPC in Stress Analysis of Stainless Steel

Advances in X-ray Analysis ◽

10.1154/s0376030800012507 ◽

1982 ◽

Vol 26 ◽

pp. 209-216 ◽

Cited By ~ 2

Author(s):

Yasuo Yoshioka ◽

Ken-ichi Hasegawa ◽

Koh-ichi Mochiki

Keyword(s):

Stainless Steel ◽

Stress Analysis ◽

High Precision ◽

Proportional Counter ◽

Stress Measurement ◽

X Rays ◽

New Model ◽

Major Disadvantage ◽

Position Sensitive

The authors previously reported stress measurement in stainless steel by the use of monochromatic Cr-Kβ X-rays and a position sensitive proportional counter. Results indicated that a stress value can be obtained with high precision on account of the subtraction of background and the elimination of αFe(211) peak by Cr-Kα X-rays. The major disadvantage of this method, however, is that the intensity of Kβ X-rays monochromatized is essentially weak and it is complicated to eliminate Kα X-rays for practical use.

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Study on Concrete Pier Impact Performance after Implementing Equal Cross-Section Stainless Steel with Protection from Closed-Cell Aluminum Foam

Shock and Vibration ◽

10.1155/2020/8869899 ◽

2020 ◽

Vol 2020 ◽

pp. 1-17

Author(s):

Xiwu Zhou ◽

Honglong Zhang ◽

Wenchao Zhang ◽

Guoxue Zhang

Keyword(s):

Stainless Steel ◽

Reinforced Concrete ◽

Aluminum Foam ◽

Bridge Piers ◽

Concrete Bridge ◽

Reinforced Concrete Bridge ◽

Impact Forces ◽

Closed Cell ◽

Steel Bars ◽

The Impact

In the present study, in order to examine the impact performances of ordinary reinforced concrete bridge piers which have been replaced by stainless-steel bars of equal cross-sections under the protective condition of anticollision material, the impact dynamic responses of the ordinary reinforced concrete bridge piers, with replacements under the protection of closed-cell aluminum foam, were compared and analyzed using an ultrahigh drop hammer impact test system. The results showed that when the impact velocity was small (for example, less than 1.42 M/s), after the implementation of equal cross-sectional replacements, the closed-cell aluminum foam had been in an elastic or yield stage. During that stage, the impact forces of the stainless-steel reinforced concrete piers were larger than those of the ordinary reinforced concrete piers, and the relative ratios were stable at approximately 28 to 34%. In addition, the relative ratios of the displacements at the tops of the components were also found to be stable at approximately 22%, and the change rates of the concrete ultrasonic damages were approximately the same. However, when the impact forces had increased (for example, more than 1.67 m/s), the closed-cell aluminum foam entered a densification stage, and the peak impact force ratios decreased sharply. It was also observed that the relative peak displacement ratios at the tops of the components displayed increasing trends, and the change rates of the concrete ultrasonic damages had displayed major flux. Therefore, the replacement of the ordinary piers with stainless-steel bars had increased the possibility of shear failures.

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