Top PDF STUDY OF VARIOUS FORGING PROCESSES WITH THEIR DEFECTS

STUDY OF VARIOUS FORGING PROCESSES WITH THEIR DEFECTS

STUDY OF VARIOUS FORGING PROCESSES WITH THEIR DEFECTS

Forged components are shaped either by a hammer or press. Forging on the hammer is carried out in a succession of die impressions using repeated blows. The quality of the forging, and the economy and productivity of the hammer process depend upon the tooling and the skill of the operator. In press forging, the stock is usually hit only once in each die impression and the design of each impression becomes more important while operator skill is less critical. The continuous development of forging technology requires a sound and fundamental understanding of equipment capabilities and characteristics. The equipment i.e. presses and hammers used in forging, influences the forging process, since it affects the deformation rate and temperature conditions, and it determines the rate of production. The requirements of a given forging process must be compatible with the load, energy, time, and accuracy characteristics of a given forging machine [1].
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A study to compare various visual field defects between glaucoma and non-glaucomatous diseases.

A study to compare various visual field defects between glaucoma and non-glaucomatous diseases.

In our study nasal steps seen in 12% cases and arcuatescotoma seen in 16% cases of glaucoma which was comparable to the study done to identify the patterns of visual field defects in an older population ( the blue mountains eyes study) at department of ophthalmology, University of Sydney, Sydney, Australia 16 in which nasal step seen in 31% cases while arcuatescotoma seen in 23% cases as they include only few types of visual field defects..

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A Study on Minimization of Critical Defects in Casting Process Considering Various Parameters

A Study on Minimization of Critical Defects in Casting Process Considering Various Parameters

order to identify the casting defect and problem related to casting. Especially industry based problem is decides to study in detail technical solution for minimizing various casting defects to improve the entire process of critical component manufacturing, is decided to work out during his project. This will be beneficial in enhancing the yield of casting. Beside this, standardization (optimization) of process parameter for entire cycle of manufacturing of the critical part is intended in the proposed work. By enhancing the quality and reducing the cost of casting component which in turn will be profitable for both the industry as well as the customer was planned in his proposed study. This was used to study the types of defects in the casting [10]. Some researchers have used statistical analysis method for optimizing process parameters of casting process.
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A Case Study on Various Defects Found In a Gear System

A Case Study on Various Defects Found In a Gear System

The joint time-frequency analysis is becoming more and more an important approach to gear/bearing damage diagnosis [10-13]. It provides an interactive relationship between time and frequency during the period of the time data window, and detects the damage of elements. They include Short Time Fourier Transform (STFT), Wigner-Ville Distribution (WVD), and Wavelet Transform (WT), etc. The STFT is the classical time- frequency analysis technique, and some gear fault can be detected by inspecting the energy distribution of a signal over the time-frequency space. The WVD is obtained by signal self-correlation and Fourier Transform processes. It was used in signal processing in early 1990s, to identified the gear fault by using the WVD. That could easily show instantaneous information of vibration energy changes. It was recently developed to detect gear failures in a rotor transmission system. The WVD is used to demonstrate the severity of the gear fault in a transmission system. The WT uses narrow time windows at high frequencies and wide time windows at low frequencies; therefore it is suitable for the analysis of transient and non-stationary signals.
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A clinical study on the various methods of reconstruction of scalp defects

A clinical study on the various methods of reconstruction of scalp defects

I understand that sponsor of the clinical study; others working on the sponsor’s behalf, the ethical committee and the regulatory authorities will not need my permission to look at my health records both in respect of the current study and any further research that may be conducted in relation to it, even if I withdraw from the study. I agree to this access; however I understand that my identity would not be revealed. In any information released to third parties or published, unless as required under the law. I agree not to restrict the use of any data or results that arise from this study. ( )
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Various Type of Defects on Pressure Die Casting for Aluminium Alloys

Various Type of Defects on Pressure Die Casting for Aluminium Alloys

Yoshihiko Hangai et al.(april-2014) In the die- casting process, the formation of pores in components is unavoidable. This porosity has a harmful effect on the strength and pressure tightness of die castings. To eliminate the porosity in components, its predominant cause has to be identified as being due to either shrinkage or gas. In practice, however, it is frequently difficult to tell the difference between porosity due to shrinkage and that due to gas from observing die castings. Accurate identification enables die casters to take corrective action. To identify the porosity accurately and to take corrective action in the die- casting process, the quantitative estimation of the morphology of pores such as their shape or spatial distribution can be a source of useful information. In this study, two types of fractal analyses are proposed to characterize the porosity in terms of the shape of individual pores and the spatial distribution of multiple pores
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Treatment of Infrabony Defects with Platelet Rich Fibrin: Case Report

Treatment of Infrabony Defects with Platelet Rich Fibrin: Case Report

[6]. Mazor Z, Horowitz RA, Del Corso M, Prasad HS, Rohrer MD, Dohan Ehrenfest DM. Sinus floor augmentation with simultaneous implant placement using Choukroun’s platelet-rich fibrin as the sole grafting material: A radiologic and histologic study at 6 months. J Periodontol 2009; 80:2056-2064.

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FORGING DEFECTS ANALYSIS IN AXLE SHAFT USING TAGUCHI METHOD

FORGING DEFECTS ANALYSIS IN AXLE SHAFT USING TAGUCHI METHOD

To check the quality of the forging parts the parts are inspected hundred percent visually for the forging defects and ten percent with the help of vernier caliper and height gauge for dimensional accuracy. In this study the percentage of rejections due to the forging defects are the quality characteristics of the forgings. To increase the quality of the forging the forged parts should be defect free.

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Analysis of the Casing Collapse in Terms of Geomechanical Parameters and Solid Mechanics

Analysis of the Casing Collapse in Terms of Geomechanical Parameters and Solid Mechanics

Casing collapse is one of the major problems in oil fields, imposing a lot of costs on oil companies. This problem occurs not only at drilling times in some formations but also after the completion and production can lead to many problems. Analysis of the behavior of casing collapse in terms of geo-mechanics and solid mechanics could significantly meet the needs of the oil industry of Iran. In this study, at first, casing collapse behavior is investigated by considering the formation creep and casing production defects using numerical methods. Then, the effect of some solid mechanics parameters on the casing collapse is investigated. The results showed that casing construction defects, such as ovality and eccentricity and residual stress, could greatly reduce the casing collapse resistance. The resistance reduction of the casing is about 30.37, 9.65, and 46.87 percent respectively, so that when the casing is placed into the well, it undergoes high strain and finally could be reached to collapse. In addition, it was found that the construction defects show a higher effect on casing collapse than the salt rock creep.
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COMPARISON OF HEALING OF BONE DEFECTS BY AUTOGENOUS
PLATELET RICH PLASMA WITH HYDROXYAPATITE AND NATURAL
HEALING IN PEDIATRIC PATIENTS

COMPARISON OF HEALING OF BONE DEFECTS BY AUTOGENOUS PLATELET RICH PLASMA WITH HYDROXYAPATITE AND NATURAL HEALING IN PEDIATRIC PATIENTS

Bone substitute materials are grafted to serve as a filler and scaffold to facilitate bone formation and promote wound healing. The present study was done to determine the efficacy of PRP with hydroxyapatite when grafted into the osseous defects in pediatric patients with age group ranging from 10-14years having same pace of bone healing rate with minimal medically compromised conditions making our data more reliable and authentic. Hypothesis behind early bone formation in PRP cases was explained by different authors as a result of action of different growth factors. There are three main growth factors; i) platelet derived growth factors (PDGF); ii) transforming growth factors (TGF); iii) insulin growth factors (IGF). PDGF induces mitogenesis, angiogenesis, fibroblastic and osteoblastic activity and macrophage activation. TGF induces paracrine growth factors which acts on fibroblast, preosteoblast and marrow stem cells. [7] IGF induces osteoblastic activity, maturation of bone and osteoclast mediated resorption. [8] These processes take place to initiate bone formation as
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Experimental Study of Longitudinal and Circumferential External Defect in Pressured Cylindrical Shells

Experimental Study of Longitudinal and Circumferential External Defect in Pressured Cylindrical Shells

Study of the Behavior of the First Cylindrical Vessels Carrying Two Longitudinal Defects The deformations raised by the various chains are represented in Figure 12, and x is the position[r]

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Preform Design in Forging and Tube Hydroforming Processes.

Preform Design in Forging and Tube Hydroforming Processes.

A new method for preform design based on shape resemblance has been presented. The proposed method is based on constructing a part slightly larger than the desired part and then performing a finite element simulation of the larger part with a reasonably guessed preform. Because the part has been enlarged and most forming defects (i.e. fold, under-fill, flash) usually occur at or close to the boundary, defects will be confined to the enlarged portion. By backwards tracing of material flow on the desired part boundaries, a preform shape can be obtained within a few iterations, which can significantly reduce the computation costs and improve the design efficiency of the forging process. This preform design method can be applied to a variety of axisymmetric forging, extrusion, and upsetting/heading problems. The specific conclusions drawn from this study are:
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Study of Self Healing Materials and Their Applications

Study of Self Healing Materials and Their Applications

In this approach, the blood clotting process was imitated via colloidal particle aggregation at the defected site using the principle of electrohydrodynamics (EHD) flow to design self-healing materials. By suspending colloidal particles which are enclosed between the walls of a double-walled metallic cylinder. The walls of this cylinder are coated with a conductive layer followed by a ceramic insulating layer. A concentric metal wire is used to apply electric field to this system. When damage occurs in the insulating layer, the current density at the damaged site is increased causing an agglomeration of the colloidal particles at the defected site through EHD flow. The aggregation of particles is insufficient to heal the defects as the voids between colloidal particles prevent formation of a dense surface. Usage of polymeric colloidal particles or a sacrificial anode for simultaneous electro-deposition of metal at the defect site to achieve better healing efficiency.
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TAGUCHI ANALYSIS OF FORGING DEFECTS FOR GEARS

TAGUCHI ANALYSIS OF FORGING DEFECTS FOR GEARS

Christry Mathew, et.al.[1] The study is focused on the forging analysis of an integral axle arm produced by hot forgings are made. Forging analysis is done to explain that how the defects occur and how to prevent them. With the help of Pareto diagram, this is mostly used to identify major areas. Then the cause and effect diagram is used to explore possible causes of defects through a brainstorming session and to determine the causes which have the greatest effect. Corrective measures are being suggested to overcome the forging defects of the integral axle arms. Finally, few remedial measures and suggestions have been provided for the existing integral axle arm production process in the forging shop.
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Forging Plant Processes Energy Conservation by Energy Audit Approach-A Case Study

Forging Plant Processes Energy Conservation by Energy Audit Approach-A Case Study

The energy audit approach is a key approach for systematic decision making in energy management. It quantifies the energy uses according to its various functions. It attempts to balance the total energy inputs with the output or the uses. The role of energy audit changes from preliminary audit to detailed audit [16]. The detailed audit goes beyond quantitative estimates to the energy cost and saving and includes engineering applications and recommendations. The preliminary audit can be used as control tool to take feed-back of the implemented projects and form basis of next project of improvements [8]. The energy conservation and maximization strategies are cost effective, which conserve the environment automatically [10]. Continues monitor and optimally control of energy use with allowance for changes in production conditions are needed [5].
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Exploration and Analysis of Strain Softening Phenomena of L6 Steel

Exploration and Analysis of Strain Softening Phenomena of L6 Steel

To analyze actual deformation in hot forging dies it is important to observe this process from start. Because, any forming process is a cyclic process. And to analyze this process we need to generate cyclic stress-strain curve and give it as an input to analysis software so that results from that analysis will be more accurate [4].

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Incremental Forging of Long Plates having Inclined Cross-Section and Local Thickening

Incremental Forging of Long Plates having Inclined Cross-Section and Local Thickening

an inclined cross-section and local thickening were developed. A long plate was compressed with an inclined punch to produce long parts having an inclined cross-section. Since local deformation was repeated in incremental forging, the forging load is comparatively small and hence small mechanical presses conventionally used in the forming industry can be used. Although waving and depression of the plate were decreased by a tapper bottom inclined punch, the plate curvature was large. A grooved die was employed to eliminate the curvature of the forged plate having an inclined cross-section. Plates having local thickening were also produced by beading and compression. The plate was freely compressed by a punch to form a beaded portion at the center of the sheet. The beaded portion was then compressed to form a local thickening without changing the width of the plate. The thick part possesses higher strength as compared to the thin part due to work-hardening during compression.
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Effect of Various Defects in Roller Bearings and Ball Bearings on Vibration

Effect of Various Defects in Roller Bearings and Ball Bearings on Vibration

Defects in a rolling element bearing may occur in the outer race, inner race, cage, or a rolling element. These faults are characterized by its own frequency, which is usually listed by the manufacturer or calculated from the bearing specifications. An impact of fault generates high-frequency vibrations in the gearbox or other structure between the bearing and response transducer. Assume that the gears in the gearbox or other attached parts are healthy and the bearings supporting the pinion shaft is affected by a localized fault in. Neglect the effects of radial load in the analysis.
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Comparative Kinetic Study of Different Bioremediation Processes for Soil Contaminated with Petroleum Hydrocarbons

Comparative Kinetic Study of Different Bioremediation Processes for Soil Contaminated with Petroleum Hydrocarbons

Bioremediation use mainly three strategies (Kaplan and Kitts, 2004); natural attenuation, biostimulation and bioaugmentation. The simplest method of bioremediation to implement is natural attenuation, where contaminated sites are only monitored for contaminant concentration to assure regulators that natural processes of contaminant degradation are active. Biostimulation requires adjustments to contaminated soil in order to provide bacterial communities with a favorable environment in which they can effectively degrade contaminants. This includes the addition of nutrients, adjustment *Corresponding author:
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Between ambiance and perception: Heritage decoding

Between ambiance and perception: Heritage decoding

Abstract. The aim of the study is to grasp and analyse the intangible process taking place between ambiance and perception. In this regard, ambiance should be understood as a state or aura, as opposed to perception, assumed as a process. The transition of sensorial immersion from ambiance to perception requires the process of decoding. Decoding might be explained as the process running between ambiance and perception and, furthermore, leading to understanding. Therefore, the outcome of the overall process is of cognitive characteristics. Furthermore, it draws research into a relationship between what is projected and actually experienced, between the tangible and the intangible and reveals the process of decoding ambiances where heritage plays a dominant role. The paper discusses the two concepts in the context of the post-industrial heritage in Łódź, Poland. The set of reflections evokes numerous questions: are we into the heritage as it was, or as it is at present, or rather to its projection, tuned to current socio-cultural standards? Does carefully planned and created ambiance give a clear unambiguous sense of a place? Or, it is not ambiance but the processes of decoding and perception that result in various interpretations of the same experience of atmosphere?
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