Blank Plate Research Articles

A Novel Incremental Sheet Bending Process of Complex Curved Steel Plate

Bending complex curved steel plates for constructing ship hull has long been a challenge in shipbuilding industry. This paper presents a novel incremental bending process to obtain complicated curved steel plates by a series of sequential and layered punches. Taking advantage of this process, the blank plate that is fixed and held by a flexible supporting system can incrementally be bent into the target shape by a press tool along a planned tool path step by step and layer by layer. Acting as a “lower die,” the flexible supporting system can provide flexible and multifunctional supports for the work piece during the forming process, whose four general motion modes are demonstrated in this paper. Meanwhile, the procedures of tool path planning and forming layering are also explained in detail. In addition, aiming at different motion modes of the flexible supporting system, two springback compensation methods are given. Furthermore, according to the forming principle presented in this paper, an original incremental prototype equipment was designed and manufactured, which is mainly composed of a three-axis computer numerical control (CNC) machine, a flexible supporting system, and a three-dimensional (3D) scanning feedback system. A series of forming experiments focusing on a gradual curvature shape were carried out using this prototype to investigate the feasibility and validity of this forming process.

Treatment of the Iron Surface and its Corrosion Resistance

Preparation and corrosion resistance of iron plate with micro-nano-structure were investigated. A clean iron plate was etched with a mixture of FeCl3, H2O, hydrochloric acid, H2O2 and H3PO4 to form a super hydrophilic surface which was treated with fatty acid solution to form a micro-nano-structure surface on which the water contact angle was about 147°. The super hydrophilic surface was treated with 3-aminopropyltriethoxysilane solution and then fatty acid solution (test plate) to turn to a super hydrophobic surface and the water contact angle was greater than 150°. This test plate coated with alkyd vamish exhibited better corrosion resistance to H2SO4 than blank iron plate.

An anti-bacterial approach to nanoscale roughening of biomimetic rice-like pattern PP by thermal annealing

In this paper, we introduced thermal annealing treatment as an effective way of increasing the nanoscale roughness of a semi-crystalline polymer surface. Annealing treatment applied to a biomimetic microscale pattern of rice leaf to achieve a superhydrophobic surface with a hierarchical roughness. Resulted surfaces was characterized by XRD, AFM and FE-SEM instruments and showed an increase of roughness and cristallinity within both time and temperature of treatment. These two parameters also impact on measured static contact angle up to 158°. Bacterial attachment potency has an inverse relationship with the similarity of surface pattern dimensions and bacterial size and due to that, thermal annealing could be an effective way to create anti-bacterial surface beyond its effect on water repellency. Point in case, the anti-bacterial properties of produced water-repellence surfaces of PP were measured and counted colonies of both gram-negative (E. coli) and gram-positive (S. aureus) bacteria reduced with the nature of PP and hierarchical pattern on that. Anti-bacterial characterization of the resulted surface reveals a stunning reduction in adhesion of gram-positive bacteria to the surface. S. aureus reduction rates equaled to 95% and 66% when compared to control blank plate and smooth surface of PP. Moreover, it also could affect the other type of bacteria, gram-negative (E. coli). In the latter case, adhesion reduction rates calculated 66% and 53% when against to the same controls, respectively.

Relationship between the changes in blood flow and volume in the finger during a Braille character discrimination task.

We hypothesized that skin blood flow (SBF) of fingers are modulated during concentrated finger perception and that the changes in SBF reflect fluctuations in finger volume (FV). The aim of this study, therefore, was examine the relationship between the changes in SBF and FV during Braille reading. We measured SBF of the finger, cutaneous vascular conductance (CVC), FV, and arterial blood pressure during Braille reading performed under blind conditions in thirty healthy subjects. The subjects were instructed to read a flat plate with raised letters (Braille reading) for 15seconds using their forefinger, and to touch a blank plate as a control for the Braille discrimination procedure. Arterial blood pressure slightly increased during Braille reading but remained unchanged during the touching of the blank plate. SBF, CVC, and FV were reduced during Braille reading (decreased by -26%, -29%, and -0.3mL/100mL respectively). Furthermore, a significant relationship was observed between the changes in SBF and FV (r=.613) during Braille reading. These results suggested that SBF of fingers is modulated during concentrated finger perception, and that the variability of blood flow reflects the response in FV.

Development of the Technology of Various Large Bodies Manufacturing Based on Combined Methods of Deformation

Metallurgy and heavy engineering construction, which are considered the most energy-intensive industries, place great focus on complex shaped thick-gage plate metal items of equipment with wall thickness exceeding 40 mm and diameter/width of up to 4000 mm. Such items of equipment include large machine parts manufactured by means of hot plate stamping, such as bodies of rotation (for example, the segment of the radial surface of converter shell, the bottom part of degassing unit, etc.) utilized as pressure-operated devices, vessels, tanks and other facilities by metallurgical, petrochemical, oil and gas, and nuclear industries. Presently known manufacturing methods of such items of equipment, for instance, stamping methods, have a number of technological problems. In the present paper, creation and development of the theory and technology of manufacturing different large bodies based on the combination of plate rolling and stamping processes, as well as the combination of asymmetric rolling and plastic bending processes, are proposed. The goal was to develop a cost-effective technology of producing large-size bodies of rotation in the conditions of a thick-plate mill. The rolling of the package forms the basis of the first stage of the new process. The package consists of the upper (punch) base, the lower (matrix) base, and the blank plate situated between them. The economic benefit from installing the developed technology based only on the combination of asymmetric rolling and plastic bending processes was more than 1 million dollars. Casings on two converters were produced and installed in the oxygen-converter plant.

Feasibility of Carbon Nanofiber Catalyst Support for the Heterogeneous Fenton Process

AbstractThe heterogeneous Fenton oxidation reaction was investigated at two different catalytic supports including the blank alumina plates and alumina plates with thin carbon nanofiber (CNF) layer. Iron (III) oxide was used as a catalyst and propionic acid (PA) was studied as a model organic compound. A carbon nanofiber layer and a thin catalytic layer of iron (III) oxide were prepared using the chemical vapor deposition method with acetylene and ferrocene precursors. The reaction rate of heterogeneous Fenton oxidation was compared with the rate of homogeneous reaction. Obtained results indicate that the reaction rate is significantly higher at homogeneous Fenton oxidation at high temperature (70°C), however, the reaction rate for homogeneous and heterogeneous oxidation is comparable at room temperature (25°C) if carbon nanofiber support is used for the iron (III) oxide catalyst.

Effects of friction factors on flat bottom self-pierce riveting joints of AZ31 magnesium alloy

Flat bottom self-pierce riveting is a novel metal sheet joining process because it does not need mold design of self-pierce riveting. Joints have flat bottom and high strength, so that flat bottom self-pierce riveting has wide development prospects. With the help of the DEFORM-2D software, this paper studied the effects of friction factors between AZ31 magnesium alloy sheets were studied, and then special simulations were carried out to investigate their effects on joints. The analysis indicates that the appropriate friction factor among blank holder, rivet, sheets and bottom plate is 0.1–0.5 and the friction factors have obvious effects on the quality of joints. The final results may provide the further research with essential guidance.

ALLISCO: pricing multiple joint products

Subjectarea Pricing, Marketing Management, Strategic Marketing, Strategic Management. Studylevel/applicability The case can be used for a Pricing Course and Strategic Marketing, Marketing Management and Strategic Management courses delivered to post-graduate management programme (Master’s level) students and/or for Management Development Programme’s. Caseoverview Alliance Intercontinental Sourcing Company LLP (ALLISCO) manufactured Steel Blanks for clutch plates used in two- and three-wheeler automobiles. Steel Blank plates further underwent a processing phase which included coating with leather cover to form the finished clutch plate. The primary raw material used by ALLISCO for its manufacturing process was sheet metal. The processing of the principal raw material resulted in the production of three joint products. The first joint product was “Steel Blank”, the main product; the second joint product was “Inner Circle”, which may be classified as a by-product; the third joint product was the left-over waste material and could be categorized as sheet scrap. The approximate increase in procurement cost of 8 per cent had considerably impacted the firm’s profit margins. The dilemma that Rishabh Singla, Managing Partner, ALLISCO, now faced was how the increased differential could be distributed systematically among the three joint products. The challenge for ALLISCO was to preserve the percentage of gross profit margins by altering its existing pricing strategy. Expectedlearning outcomes Understand the concept of multiple joint products; learn about choosing appropriate pricing strategies to price multiple joint products; comprehend how value-based pricing can extract untapped profits; and understand the importance of retaining gross profit margins (%). Supplementarymaterials Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Optical properties of laser sintered polyamide 12

Purpose – The purpose of this paper is to report selected optical properties of laser sintered polyamide 12 blank plates under different monochromatic and white light conditions and to apply these properties in production of laser sintered lithophanes. Design/methodology/approach – A UNICO 1201E spectrophotometer was used to measure the transmittance of laser sintered polyamide 12 plates as a function of plate thickness. Monochromatic light-emitting diodes were used to assess the wavelength dependence on the transmission and contrast as captured by a SONY DSC-W55 camera. Findings – The transmittance decreased with increasing plate thickness which varied significantly depending on the monochromatic wavelength. Highest transmission was observed using green light (525 nm) and poorest transmission was measured for yellow light (589 nm). Research limitations/implications – There is a limit to the amount of contrast obtained in polyamide lithophanes because the thickness of the plates is limited to less than about 5 mm. Greater thickness results in discernible topology on the lithophane which impairs the quality of the image. Originality/value – Light transmittance of polyamide 12 plates under different lighting conditions is reported and applied to optically defined laser sintered lithophanes.

Aminolevulinic acid-mediated photodynamic therapy of human meningioma: an in vitro study on primary cell lines.

Objective: Five-aminolevulinic acid (5-ALA)-induced porphyrins in malignant gliomas are potent photosensitizers. Promising results of ALA-PDT (photodynamic therapy) in recurrent glioblastomas have been published. Recently, 5-ALA-induced fluorescence was studied in meningioma surgery. Here, we present an experimental study of ALA-PDT in an in vitro model of primary meningioma cell lines. Methods: We processed native tumor material obtained intra-operatively within 24 h for cell culture. Epithelial membrane antigen (EMA) immunohistochemistry was performed after the first passage to confirm that cells were meningioma cells. For 5-ALA-PDT treatment, about 5000 cells per well were seeded in 20 wells of a blank 96-well plate. Each block of 4 wells was inoculated with 150 µL of 0, 25, 50 and 100 µg/mL 5-ALA solutions; one block was used as negative control without 5-ALA and without PDT. Following incubation for 3 h PDT was performed using a laser (635 nm, 18.75 J/cm2). The therapeutic response was analyzed by the water soluble tetrazolium salt (WST-1) cell viability assay 90 min after PDT. Results: 5-ALA-PDT was performed in 14 primary meningioma cell lines. EMA expression was verified in 10 primary cell cultures. The remaining 4 were EMA negative and PDT was without any effect in these cultures. All 10 EMA-positive cell lines showed a significant and dose-dependent decrease in viability rate (p < 0.001). Cell survival at 5-ALA concentrations of 12.5, 25, 50 and 100 μg/mL was 96.5% ± 7.6%, 67.9% ± 29.9%, 24.0% ± 16.7% and 13.8% ± 7.5%, respectively. For the negative controls (no 5-ALA/PDT and ALA/no PDT), the viability rates were 101.72% ± 3.5% and 100.17% ± 3.6%, respectively. The LD50 for 5-ALA was estimated between 25 and 50 µg/mL. Conclusion: This study reveals dose-dependent cytotoxic effects of 5-ALA-PDT on primary cell lines of meningiomas. Either 5-ALA or PDT alone did not affect cell survival. Further efforts are necessary to study the potential therapeutic effects of 5-ALA-PDT in vivo.

Minimization of sheet thickness variation and other defects of mini drawn parts using a blank holder plate made from concentric rings

Thickness variation is a major defect of the drawn parts made from sheet metals, which influences the intensity of part defects and may cause part failure. In the case of mini deep drawing, sheet thickness variation along part's profile has the following effects on the drawn part geometry: increased non-uniformity of diameter variation, variation of springback parameters (part edge radius deviations and angle of wall inclination), different wrinkling intensities, and part cracking and fracture. The present paper analyses the experimental results of the investigations concerning the sheet thickness variation in the case of mini cylindrical drawn parts made from a copper alloy. Some constructive solutions of tool components that allow the control and minimization of sheet thickness variation by controlling the blank holder force, contact and friction forces (especially in the part flange zone) are also proposed and tested by simulation and experiment. The constructive solutions of the new tools were obtained by constructing the blank holder plate from two concentric rings made from different materials with equal or unequal widths.

Analyzing the phytochemical composition of Justicia neesii Ramam)

Phytochemical profile is an important aspect as it will give an over view of possible pharmacological properties of the plant. Justicia neesii is a plant belongs to Acanthaceae family, on which no significant phytochemical and pharmacological was done. The objective of the present study is to elucidate the phytochemical profile and analysis of antioxidant properties by TLC method. The phytochemical analysis was done for screening the maximum number of phytochemicals using standard methods. The TLC plates were developed with a solvent system containing methanol: chloroform: hexane at a ratio of 7:2:1. Ascorbic acid was used as positive control and a blank TLC plate was used as negative control in the experiment. The diluted DPPH in methanol was sprayed on the developed plates and observed under UV light. The preliminary phytochemical analysis shows the presence of flavonoids, glycosides, lactones, lignins, phenols, phytosterols, quinins, reducing sugars, saponins and terpinoids. The TLC analysis has shown the higher intensity of yellow color for the test spots which indicating the higher antioxidant potential of plant extract compared to standard ascorbic acid after treatment with DPPH solution. The plant is having good antioxidant potential. The plant was also composed of many significant phytochemicals.

Recent Development on Theory and Application of Variable Gauge Rolling, a Review

Variable gauge rolling (VGR) is a new technology for producing the materials which have the advantage of lightweight due to optimized thickness according to load distribution. The new progresses in the theoretical research and application of VGR are reviewed in this paper. Two basic equations, VGR-f and VGR-s, were deduced. The former is a new differential equation of force equilibrium, and the latter is a new form of formula for the law of mass conservation. Both of them provide a new base for the development of VGR analysis. As the examples of VGR’s application, tailor rolled blank (TRB) and longitudinal profile (LP) plate are introduced. Now TRBs are only produced in Germany and China, and have been used in the automotive manufacturing to play an important role in lightweight design. LP plates have been used in shipbuilding and bridge construction, and promised a bright prospect in reducing construction weight. In addition, new technologies and applications of VGR emerge constantly. Tailor welded strips and tailor rolled strips with variable thickness across the width can be used for progressive die and roll forming. The 3D profiled blank can be obtained by two-step rolling process. Tailor tubes with the variable wall thickness are an efficient way to reduce the weight. The blank with tailored thickness and mechanical property is also under development. Above products based on the tailored ideas provide a new materials-warehouse for the designers to select so as to meet the needs of weight reducing and material saving.

Applied State Space Feedback Control of a Deep Drawing Process

This paper presents results from application of discrete state spacebased feedback control of the blank holder force (BHF) magnitude and distribution in the drawing ofa rectangular workpiece. By means of monitoring the flange draw-in during the punch stroke, the controller makes continuousadjustments to the BHF magnitude and distribution by individuallycontrolling the pressure of a hydraulic fluid in a number of cavitiesembedded in the blank holder plate. The adjustments are conducted onlineduring the punch stroke to minimize the deviation of the achieved flange draw-in from a predetermined reference.

Reduction of the sheet thickness variation and its negative effects on the accuracy of mini drawn parts using different geometries of tool components

Like in the case of macro deep drawing, the sheet thickness of mini drawn parts, with dimensions smaller than 20mm and made from very thin sheets, is unevenly distributed and varies from minimum values resulted in the zone of part edge radius to maximum values in the upper zone of part vertical walls. Such variation of sheet thickness can cause for the resulted drawn parts some geometric deviations from their theoretic geometry or it can determine the parts failure. Hence, the main objective of the mini scale deep drawing processes is to obtain an increased accuracy by reducing the sheet thickness variation, or in other words to minimize the values of sheet thinning and thickening. The present paper analyses the results of investigations made by experiment and simulation concerning the use of different geometries of the tool components that permit to control and minimize the sheet thickness variation in the mini cylindrical drawn part zones where this phenomenon can generate negative effects and determine the part inaccuracy. The new geometries of tools were obtained by modifying the state of stress in the deformed sheet using adequate geometries of active surfaces of the die cavity and blank holder plate.

The Optimization to the Die of Concave-Convex Blanking Material

To increase the service life of the die in blanking stainless steel plate, this paper tries to optimize the blanking die. By adopting reasonable lifting and pushing structure in the die to realize up-put the concave and down-lie the convex which adds the sharpening repair times of concave-convex die. The study finds that the die is easy to operate and maintain and has the character of repeating sharpening repair after one-time heat treatment, which can greatly prolong the dies service life and is suitable to bulk blank stainless steel plate.

In‐plane alloy electrodes for capacitively coupled contactless conductivity detection in poly(methylmethacrylate) electrophoretic chips

A simple method for producing PMMA electrophoresis microchips with in-plane electrodes for capacitively coupled contactless conductivity detection is presented. One PMMA plate (channel plate) is embossed with the microfluidic and electrode channels and lamination bonded to a blank PMMA cover plate of equal dimensions. To incorporate the electrodes, the bonded chip is heated to 80 °C, above the melting point of the alloy (≈ 70 °C) and below the glass transition temperature of the PMMA (≈ 105 °C), and the molten alloy drawn into the electrode channels with a syringe before being allowed to cool and harden. A 0.5 mm diameter stainless steel pin is then inserted into the alloy filled reservoirs of the electrode channels to provide external connection to the capacitively coupled contactless conductivity detection detector electronics. This advance provides for a quick and simple manufacturing process and negates the need for integrating electrodes using costly and time-consuming thin film deposition methods. No additional detector cell mounting structures were required and connection to the external signal processing electronics was achieved by simply slipping commercially available shielded adaptors over the pins. With a non-optimised electrode arrangement consisting of a 1 mm detector gap and 100 μm insulating distance, rapid separations of ammonium, sodium and lithium (<22 s) yielded LODs of approximately 1.5-3.5 ppm.

Optical thickness measurement of mask blank glass plate by the excess fraction method using a wavelength-tuning interferometer

The absolute optical thickness of a 140-mm2 mask blank glass plate 3.1mm thickness was measured by three-surface interferometry using a wavelength-tuning Fizeau interferometer. The interference order was determined by the excess fraction method. The wavelength of a tunable laser diode was scanned linearly from 632 to 642nm, and a CCD detector recorded 2000 interference images. Two kinds of optical thicknesses measured by discrete Fourier analysis and phase-shifting were synthesized to obtain the optical thickness with respect to the ordinary refractive index. The optical thickness defined by the group refractive index at the 637nm central wavelength was measured by wavelength scanning. The optical thickness deviation defined by the ordinary refractive index was measured using tunable phase-shifting. The systematic errors caused by nonlinearity in the wavelength tuning were corrected through correlation analysis between the theoretical and observed interference fringes.

Experimental verification of a deep drawing tool system for adaptive blank holder pressure distribution

In deep drawing, the strain path in the blank during the forming process can be significantly affected by application of temporal and spatial variation of the blank holder force. In this study, an active tool system capable of controlling the distribution of the blank holder force is presented which can be integrated into existing stacked deep drawing tools without need for modification of the press.A working system is presented consisting of a controller, designated volume displacement cavity pressure supply units and a shimming plate. It is applied to the deep drawing of a rectangular geometry using a conventional stacked tool design. The shimming plate is used to support the blank holder plate, and has four integrated hydraulic cavities in which the pressure can be controlled individually whereby a controlled deflection of the blank holder plate is achieved analogous to the conventional shimming method using paper or metal shims between the tool plates.The tool system's ability to influence the material flow is investigated by performing a series of deep drawing experiments. Eight different cavity pressure schemes are applied during the punch stroke and the scheme's effects are documented by means of process data and 3D-coordinate measurements of the formed parts demonstrating that both the geometric shape and the thickness distribution in the formed parts can be affected by the shimming system.

Modulation of radial blood flow during Braille character discrimination task

Human hands are excellent in performing sensory and motor function. We have hypothesized that blood flow of the hand is dynamically regulated by sympathetic outflow during concentrated finger perception. To identify this hypothesis, we measured radial blood flow (RBF), radial vascular conductance (RVC), heart rate (HR), and arterial blood pressure (AP) during Braille reading performed under the blind condition in nine healthy subjects. The subjects were instructed to read a flat plate with raised letters (Braille reading) for 30 s by the forefinger, and to touch a blank plate as control for the Braille discrimination procedure. HR and AP slightly increased during Braille reading but remained unchanged during the touching of the blank plate. RBF and RVC were reduced during the Braille character discrimination task (decreased by -46% and -49%, respectively). Furthermore, the changes in RBF and RVC were much greater during the Braille character discrimination task than during the touching of the blank plate (decreased by -20% and -20%, respectively). These results have suggested that the distribution of blood flow to the hand is modulated via sympathetic nerve activity during concentrated finger perception.