Press Capacity Research Articles

Experience in solving the problem of filtering and washing unstructured sediments of hydrometallurgical processing of polymetal sludge

The article aims to select a filter design and mode of washing cake in the hydrometallurgical processing of polymetallic sludge in order to minimize the volume of washing water and obtain a high-quality cake—iron oxide pigment precursor. An analysis of the chemical composition of the subject matter–pulp following hydrochloric acid treatment of polymetallic sludge—was performed using atomic absorption spectrophotometry and X-ray fluorescence spectrometry, while the particle size distribution was studied via laser diffraction. The analysis of the chemical composition revealed that the liquid phase contains, g/dm3 : MgCl2 90.5–105.6; AlCl3 35.8–37.6; NiCl2 8.1–9.0; FeCl3 24.5–27.1; CrCl3 5.9–6.5; MnCl2 2.1–2.4; HCl 6.5–7.7. The solid particles present in the pulp are represented by two distinct groups of particles having the following sizes: 0.1–1 µm and 1–120 µm. It was found that pulp separation using a chamber-membrane filterpress with the vertical arrangement of plates minimizes washing water volume up to S:L 1:1, returns the mother liquor captured by the cake to the process cycle, and helps to obtain high-quality washed cake with a minimum content of residual salts (0.5 wt%). The optimal temperature of the pulp entering the filtering process is 80℃, while that of washing water is 60℃. Cake washing was shown to be the limiting step of the pulp separation process, which can be realized via the displacement method given the use of acidified water with pH 1.5. It was found necessary to use filter cloths made of 100% polypropylene, with a specific weight of the fabric of 540 g/m2 ± 10%, air permeability of 6 L/dm2 per minute ± 30% at 200 Pa, and a maximum operating temperature of at least 90ºC. Thus, the specific capacity of the filter press was calculated and a standard machine with the vertical arrangement of plates and a filtering surface of 500 m2 was selected for pulp separation following hydrometallurgical processing of wet polymetallic sludge (8000 tons/year).

Underground Press of Social Democratic Organizations in Šiauliai in 1904–1914

This article deals with propaganda activities, such as publishing proclamations (20 publications), revolutionary songs (1), and underground periodicals (1), by local organizations of the Bund, LSDDP, LSDP and RSDDP in Šiauliai in 1904–1914. Political changes in Russia in 1904–1907 created favorable conditions for social democratic organizations to actively carry out propaganda activities, but the intensity at which they were carried out was not uniform across Lithuania. The proletarian profile of Šiauliai and the particularly active activity of the LSDP allowed to mobilize propagandists in a short time, to prepare the necessary proclamations on the spot, and to provide the necessary press equipment. During the years of the revolution (1905–1907), Šiauliai had to emerge as the second center of the social democratic movement in Lithuania. After the defeat of the revolution in Russia, due to the increased persecution of social democratic forces, the underground organizations failed to mobilize their press capacity or develop more active propaganda events; therefore, the political parties even had to suspend the activities of local organizations in Šiauliai. The integration of social democratic youth into the social democratic organizations of Šiauliai took place in c. 1912 and gave hope for a stronger revival of propaganda. The resumption of activities ceased in the first years of the First World War. The large-scale underground press developed in underground conditions expressed the expectations of the local population, reflected the involvement of parties in the formation of political views of the urban population, and was a counterweight to official information. Therefore, its assessment is inseparable from the realities of the political context of that time.

Compressive Strength, Wear, and Structure Characteristics as a Result of Silicon Carbide Addition on a Copper Base

The current research aims to study of the effected of the reinforced materials on the extent of failure or resistance of the metals. The powder method was used to manufacture models of copper-based composites, then copper was reinforced by silicon carbide at percentages of (0,5,10,15,20)%, and alumina was used as a fixed support at (10% Al2O3), Moreover, the mixture was ground by a steel mill for 2, 4, and 6 hours and then pressed with a press capacity of 20 tons. The homogeneous mixture was placed inside a steel mold and pressed at 5 tons for a time of one minute. After sintering at 900°C for two hours, the samples were prepared. The diagonal compressive strength tests, the wear test and examination of an atomic force microscope in three different grinding periods were carried out. The results of the examination showed that the highest compressive strength was obtained (53.3 Mpa) at a six-hour grinding time with a percentage of 20%SiC, while the wear rate showed a decrease in its value as it was less weary at a six-hour grinding time, and at a percentage of 20%SiC also (1.10368 * 10 -7 g/cm). The images obtained from the atomic force microscope showed that the total surface topography and the morphology of the grains formed on the surface have a high degree of homogeneity and arrangement after the heat treatment. We observed the regularity in the growth of the superimposed layer and noted that the grains were arranged perpendicular to the axis. As the crystalline heights are approximately equal, the best characteristic parameters of the results were found at sintering of 900°C, grinding time of six hours, and cementing content of 20%.

Numerical assessment of large hexagonal seamless steel tube extrusion feasibility

The study assesses feasibility of hot extrusion of a large seamless hexagonal 9%Cr-1%Mo steel tube. The manufacturing chain starts from a pierced cylindrical billet, hot extruded and to be further cold drawn in several passes. Preliminary industrial tests have shown thickness reduction in extrusion limited by a huge initial force peak (+25 %) reaching the press capacity. To understand this force peak, thermomechanical numerical simulation (ForgeNxt®) of the furnace-press transfer and extrusion stages is carried out. Constitutive model at high temperature, high strain and strain rate has been selected from literature. Surface properties, namely Heat Transfer Coefficient (HTC) and friction coefficient, have been made space- and time-dependent to represent glass lubrication. Numerical results are qualitatively compared to industrial experimental values to evaluate the prediction of the model. It suggests that the difficult start of the glass melting and flow along a cooled die affects the force peak. Practical improvements are suggested on this basis, together with possible refinements of the simulation for more precision and insight into extruded tube quality.

Determining temperatures and forces necessary to produce hot-pressed tubes out of titanium alloy PT-1M

This paper describes the results of a study that looked at alloy PT-1M that refers to the Ti – Al system and the α-alloys of titanium and is used to make tubes for various applications, including tubes that are hot-pressed as part of the manufacturing process. When developing a procedure for making hot-pressed tubes, one should first determine the temperatures and forces of the pressing operation that would ensure production of quality semifinished tubes. By means of test quenching operations, optical microscopy, thermodynamic analysis performed in ThermoCalc and physical modelling of the hot deformation process carried out in Gleeble 3800, as well as a series of mathematical calculations, the authors were able to determine the polymorphic α + β → β transformation temperature, as well as temperature regions of heating and forces that are necessary for hot pressing of the titanium alloy PT-1M for producing tubes of a given size at the TMK Group facilities. Having analyzed the temperature region of the α + β → β transformation in alloy PT-1M through thermodynamic calculation in ThermoCalc, the authors came up with recommended test temperatures for the PT-1M alloy for estimating the hot deformation forces required. The authors simulated the process of hot deformation by compressing specimens of the PT-1M alloy in the recommended temperature range, explained how the forces changed as a function of temperature and true deformation rate and determined the maximum forces and the strain-induced heating. The calculations show that, in the temperature range recommended for pressing tubes of a given size from PT-1M workpieces, the peak loads do not exceed the capacity of the pipe press in view. This research was funded by the Russian Science Foundation (Project No. 18-79-10107).

Study on dynamic characteristic and forging capacity of the direct drive press with symmetrical toggle booster mechanism driven by TPMLM

Compared with the conventional servo press, the direct drive press even has no transmission mechanism, so it has advantages in controllability, precision and energy management. But, the forging capacity of the direct drive press is limited by the power of the linear motor. In this paper, a novel press driven by a tubular permanent magnet linear motor (TPMLM) is presented, and a symmetrical toggle booster mechanism is specially proposed to enhance the forging capacity. The mathematical model of the toggle booster mechanism is established, The TPMLM is designed, and the experimental prototype of the novel press is manufactured. The forging capacity and dynamic characteristics of the press are studied theoretically and experimentally. The results show that the introduction of the symmetrical toggle booster mechanism enriches the dynamic characteristic curve of the press and enhances the forging capacity. Therefore, the structural parameters of the toggle mechanism and the working position of the slider can be adjusted to meet different technological requirements. In addition, based on the research work, three directions are proposed to improve the forging capacity of the novel press. The research contributes to the performance optimization and development of direct drive press.

David Garrick and the Mediation of Celebrity by Leslie Ritchie

Reviewed by: David Garrick and the Mediation of Celebrity by Leslie Ritchie Emrys D. Jones Leslie Ritchie, David Garrick and the Mediation of Celebrity (Cambridge: Cambridge Univ. Press, 2019). Pp. 312; 11 b/w illus. and 3 tables. $99.99 cloth. The magnitude of David Garrick's fame is firmly established, trumpeted as it was from an early stage of the actor-manager's career and now accepted as something of a self-evident fact by historians of celebrity culture. It can be tempting, given the wide array of texts and artifacts attesting to Garrick's renown, to explain it either as the result of incredible natural ability, or—if one acknowledges his business acumen at all—as a fluke convergence of public taste and theatrical strategy. With singular focus and discussion of newly unearthed material, Leslie Ritchie's David Garrick and the Mediation of Celebrity argues that we should attend still more closely to Garrick's cultivation and protection of his own "brand." While not rejecting genuine talent as a possible factor in his reputation, she demonstrates that Garrick's manipulation of the wider media landscape and his management of negative publicity were just as crucial for his celebrity, and were in fact the elements distinguishing his peculiarly modern public profile from anything that had come before. Celebrity is, according to this analysis, not merely a more artificial or more immediate kind of fame, but "an iterative form of public recognition that is the product of repeated media exposures across multiple media platforms" (10). Ritchie's introduction makes this argument and contextualizes it within the fields of celebrity studies and Garrick studies, particularly demonstrating how even seminal works such as George Winchester Stone, Jr. and George M. Kahrl's David Garrick: A Critical Biography (1979) have underplayed the actor's media influence even as they overestimated the press's capacity for—or aspiration to—impartial judgement. These points are convincingly corroborated in the five chapters and coda that follow. Chapter One provides an overview of the media landscape, and more specifically the function and organization of newspapers, during Garrick's career, as well as reflecting on his own habits of informed newspaper reading. Chapter Two progresses to a detailed reconstruction of Garrick's ownership of newspaper shares, a situation which Ritchie describes using the modern business terminology of "vertical integration" (55). Such a framework (in which a business owns and controls its own supply chain) perhaps too readily casts the newspapers as subordinate to the demands of Garrick's theatrical projects, but it helps to explain the sheer extent of his media reach, the sense that his "name, writing and reputation were inescapable elements of eighteenth-century culture, even if one never attended the theatre" (60). Chapter Three elaborates on this by exploring the different avenues for theatrical advertisement available in Garrick's time, from the paid-for paragraphs that were subject to taxation to less easily identifiable (hence non-taxable) promotional verse and "puffery." From there, the chapter anatomizes some of the most notable facets of "Brand Garrick" consolidated through such channels: for instance, the popular fascination with his captivating eyes and his celebrated ability to excel in both tragic and comedic roles. As well as promoting these various aspects of his reputation, and above all capitalizing on variety itself as the basis of his popular appeal, Garrick was also skilled in his handling of negative publicity. Chapter Four of Ritchie's book finds the actor and his defenders both countering and pre-empting attacks upon him. It becomes clear that apparent physical deficiencies—his short stature and absences from the stage due to illness—were regularly manipulated to Garrick's benefit. In [End Page 743] works such as Garrick's own anonymously-published Essay on Acting (1744) and Tobias Smollett's "The Character of Mr. Garrick" (1742), shortness was reframed as "perfection of proportion" (118). Published apologies for bouts of sickness or exhaustion likewise ended up contributing to his brand rather than detracting from it, creating what Ritchie describes as a "culture of care" around him and assisting in the depiction of tragic performance as physically and emotionally demanding work (128). The Garrick presented in this chapter...

Finite element analysis of heat transfer performance of vacuum glazing with low-emittance coatings by using ANSYS

As a new transparent insulation material, vacuum glazing with Low-E (low emittance) coating has drawn more and more attentions thanks to its excellent performances: outstanding thermal and sound insulations, anti-frosting, resisting wind press capacity, and good durability. However, a comprehensive analysis and evaluation on the heat transfer performance of Low-E vacuum glazing are still missing in the current literatures. In this work, the influences of various aspects on the heat transfer performance of Low-E vacuum glazing were analyzed based on the Finite Element Analysis (FEA) method, including thickness of substrate glass, width of the sealing edge, materials and spacing of support pillar array, and insulation frame structure. The simulated results show the following, 1) with the increase of the thickness of the substrate glass, the heat transfer coefficient of the Low-E vacuum glazing rises slowly in a linear trend. The larger the size of the whole piece of the glazing, the more slowly it rises; 2) the Low-E vacuum glazing heat transfer coefficient declines linearly with the decrease of the width of the sealing edge; 3) as the support pillar array spacing increases and the thermal conductivity of the support pillar array decreases, the Low-E vacuum glazing heat transfer coefficient decreases; 4) the use of thermal insulation frame structure can improve the insulation efficiency of the vacuum glazing. Experiments were carried out on a Low-E vacuum glazing, and the heat transfer coefficient of this vacuum glazing was determined by the Building Heat Resistance-III (BHR-III), an equipment for insulation performance testing. The simulated result matches well with the experimental result, with a relative deviation of 2.8%, which confirms the reliability of the simulation result. This work is expected to provide guidance for optimization design of Low-E vacuum glazing and its insulation performance evaluation.

Performance evaluation of analytical expressions for cylindrical and rectangular deep drawing force estimation

The deep drawing force (DDF) is defined as the maximum force required to perform a given deep drawing operation. The DDF is needed to design the drawing tools, to define the press capacity and to estimate the drawing work and process efficiency. Although several expressions to estimate the DDF have been proposed in the literature, particularly for cylindrical parts, very few research works have focused on their evaluation in terms of prediction performance. Moreover, a limited number of expressions to estimate the DDF of rectangular parts have been reported in the literature.In this paper, an investigation to evaluate and compare different analytical expressions to estimate the DDF of cylindrical and rectangular parts is presented. The aim of this investigation is twofold: first, to propose new expressions to estimate the DDF of rectangular parts, and second, to evaluate the prediction performance of the DDF expressions for cylindrical and rectangular parts. Initially, several DDF expressions for cylindrical parts are identified and analysed. These expressions are then transformed into equivalent expressions for rectangular parts by using the equivalent diameter concept. The prediction performance of these DDF expressions for cylindrical and rectangular deep drawing is then quantified and analysed based on experimental data from the literature. Finally, the influence of the deep drawing parameters on the DDF is also presented and analysed.

Towards a CFD-based analysis of a full-scale sludge tank to enhance dewatering capacity of the downstream filter press

Abstract A computational fluid dynamics (CFD) model was developed for sludge mixing-settling in a laboratory scale sludge tank based on the Takacs exponential function. A dynamic experimental program was also undertaken at different rotational speeds of mixers and the concentration of sludge to validate the sludge sump model. The deviation between the simulated interface height and the experimental data was 2%. The validated CFD model was then employed to develop a novel operating methodology for operation of a full-scale sludge tank. The proposed model includes two consecutive periods of sludge mixing and settling, resulting in reducing the mixers’ working time. In the current operating mode, the energy consumption of mixers has been reduced by 91.67%. Based on the two-phase, 3-D modeling results of the sludge tank, the post-construction sludge tank is simultaneously able to act as a secondary clarifier, as well as a storage tank. As a key finding of the study, the treatment capacity of the filter press in downstream has accelerated, so that the working hours and energy consumption of the filter press has been improved by 55%.

Characterization of oilseeds mechanical expression in an instrumented pilot screw press

This work studies oil seeds mechanical expression in a screw press. For this purpose, a pilot-scale screw press (0–40 kg/h) was instrumented by installing sixteen pressure sensors and three temperature probes throughout the screw. Canola (Brassica napus L) and flax (Linum usitatissimum) seeds were used for investigation. The impact of the screw rotation speed on the press performances and the matter flow inside the press was investigated. The screw press capacity, passage time, extraction yield and specific energy consumption were studied is the range of 0–18.2 rpm. For each experiment the radial pressure, the internal residual oil content and the matter velocity evolution were measured all along the screw.Results show that increasing the rotation speed enhances the press capacity and decreases the passage time, reduces the extraction yield and the specific energy consumption. The recorded data allowed the identification of different functional sections of the screw press (feed, compression and mixing/relaxation sections) in relation with the screw geometry. In the compression sections, high pressure leads to oil expression and the formation of hard cake. In the mixing sections, pressure falls to zero and press-cake becomes friable. The matter velocity in the mixing sections is quick as compared to that in compression sections. Furthermore, results show the existence of oil reflux phenomena inside the screw press cage.Based on the obtained results, the continuous screw press behavior was schematized as a succession of several individual batch presses with intermediates steps of press-cake mixing and oil refluxes in order to facilitate process modeling.

IMPACTS OF BALING PRESS AT GINS ON COTTON QUALITY

the performance of cotton baling press used (bale press type HUTA KROL model NP. 30) in Egyptian scutchers was evaluated. This bale press was determine the influence of bale weight (kg), bale volume (m³), bale density (kg/m³), bale press capacity (bale/h), power requirement (kw), total bale press cost requirement were investigated. Also, all of staple length 2.5%(mm), staple length 50%(mm), strength(g/tex), elongation (%), lint grade(degree) and trash content (%) were evaluated and tested at four levels of lint moisture content of 11.2, 9.8, 8.7 and 7.3% d.b, three levels of tramper strikes of 7, 10 and 14 stroke/bale and four levels of piston compressor of 1422, 1765, 2206 and 2600 N/cm². The obtained results show that, the highest value of bale weight and bale volume were 400 kg and 0.757m³, the highest value of bale density was 552.5 kg/m³ and the maximum value of productivity was 1400kg/h. also, minimum value of power required was 11.9kw and minimum value of total bale press cost requirement was 141L.E/h. On other hand, results found that studying the characteristics of lint cotton quality at bale press was clear that all the qualities were good to production bales of cotton press when moisture content was less than 11.2% d.b, and more than 7.3% d.b.

Performance of mechanical co-extraction of Jatropha curcas L. kernels with rapeseed, maize or soybean with regard to oil recovery, press capacity and product quality

Jatropha curcas L. shelled seeds (kernels) have been gaining attention as protein source due to their high protein content. However, due to the soft texture, screw pressing the kernels resulted in a low performance, which was indicated by high residual oil content in the press cake. In order to overcome the low oil recovery from the extraction process, J. curcas kernels blended with rapeseed, maize or soybean as additives were studied. The blending effects on the performance of mechanical oil extraction, along with the quality of oil and press cake were evaluated. To achieve the maximum oil recovery, blending ratio, nozzle diameter and screw speed were optimised using response surface methodology. Higher blending ratio showed significantly higher oil recovery (p<0.05). Soybean blend exhibited highest oil recovery of 91.0%. Specific energy requirement and oil recovery were negatively correlated with throughput. Oil from maize blend generated the highest acid value and free fatty acid of 8.39mg KOH/g and 4.19%, respectively. Carbon residue of the sedimented oil from all material blends fulfilled the standard threshold of German Institute for Standardization (DIN 51605). The highest press head temperature of 104.6°C was observed from soybean blend. The ash content of the press cake from pure J. curcas kernels was lower than the other material blends. Press cake from soybean blend revealed low pepsin insoluble nitrogen and high crude protein content, pepsin plus trypsin digestibility and available lysine. Regarding the antinutritional factors, press cake from rapeseed blend showed highest phytate and trypsin inhibitors of 4.1% and 22.7mg trypsin inhibited/100mg sample, respectively. In terms of oil recovery and press cake quality, soybean appears to be the most suitable additive compared with rapeseed and maize.

Evaluation of the pressing process during oil extraction from grape seeds

This study evaluated the physical properties and oil extraction from grape seeds from three white (Welschriesling, Green Veltliner, Hibernal) and two red (Zweigelt and Saint Laurent) must varieties of grapevine by cold screw pressing as the appropriate extraction process. Pressing was carried out by a screw press UNO FM 3F by Farmet Company, Czech Republic. The pressing device consists of a matrix, 220 mm screw, head, heating mantle, nozzle holder, and a nozzle of 10 mm in diameter. The minimal and maximal screw rotation speeds were chosen within the press characteristics in order to achieve a correct expression and to avoid press overload. For successful pressing of the seeds and their storage, their initial moisture content was lowered from 40 to 45% to about 5 to 8% in a chamber dryer. The temperature in the chamber dryer did not exceeded 40 °C. Seeds of all varieties were pressed at the same speeds of 20, 40, 60, and 80 rpm. The characteristics of the grape seeds are as follows: The density ranges from 602.7 to 606.3 kg.m-3, thousand seeds weigh is between 21.9 - 26.6 g, humidity between 5.6 - 7.1% of dry matter and seed oil content, determined by extraction and depending on the variety, ranges from 15.3 to 17.5% in dry basis. The results have confirmed that when the screw rotation speed is changed from 20 to 80 rpm, the press capacity increases on average from 0.84 kg.h-1 to 1.75 kg.h-1, but simultaneously the oil yield reduces from 9.85 to 6.75%. This means that one kilogram of seed may produce 67.5 to 98.5 g of oil. The quantity of the pressed oil ranges from 67.5 to 98.5 g.kg-1 and thus depends on the variety. The measured results can be used in commercial practice for optimizing the pressing process for pressing of oil from grape seeds.

Effect of radial interference on torque capacity of press- and shrink-fit gears

Some gears in an automobile transmission have to be mounted by being press-fitted on a shaft instead of splines. The torque capacity of the press-fitted gear will be proportional to the radial interference. The excessive interference, however, will increase the gear radial deformation. In this paper, the press- and shrink-fit and the subsequent torque capacity test were investigated by finite element analysis, theoretically and experimentally. The static and dynamic coefficient of friction were determined.

Microstructure and texture evolution of AA 6063 during an Ex-ECAE process

Equal channel angular extrusion (ECAE) has been studied at the lab scale for many years. However, few successful industrial applications of the ECAE process have been reported. In the present work, a process referred to as Ex-ECAE that was composed of two processes of the direct extrusion and the ECAE via route C, was developed. The Ex-ECAE process was developed to refine the microstructure of the extrudate, particular the coarse grain layer (CGL) on the surface of the extrudate. The Ex-ECAE die with a die angle of 120° contained three segments and was used in the conventional direct extrusion press. The high friction and the continuous routes of the ECAE resulted in asymmetric dead metal zones (DMZs) to be formed at the corners of the die channel. It revealed that the visible grains in the CGL were refined and became invisible due to the intense shear deformation as the CGL flowed along the boundaries of the asymmetric DMZs. The textures of the Ex-ECAE at the various segments were studied by EBSD. This study demonstrated that the ECAE process could be scaled up using the extrusion press. Success or lack of success depended on the capacity of the extrusion press and the die design.

Interred in Printing House Vaults: Pianotype Composing Machines of the 1840s

Nineteenth-century pianotype composing machines were designed to mechanize the labour-intensive process of setting type by hand. The term describes a range of inventions that involved a user depressing keys to select type for composing. However, despite rapid advances in the speed and capacity of the printing press, mechanization failed to progress until the invention of the Linotype by Ottmar Mergenthaler in 1886. This essay argues that the pianotype composing machine is not just a footnote in the history of the inevitable rise of the Linotype machine but an artefact that interrogates preconceived ideas of the compositor’s role. It asks why the mechanization of compositing in the 1840s and 1850s involved keyboards inspired by the workings of the pianoforte. The essay discusses pianotype composing machines in terms of their historical context and the controversy and interest they engendered. It examines early attempts at mechanization in the 1840s, using the case history of the Young and Delcambre machine to demonstrate the obstacles to commercial development. It suggests that these inventions embodied a key step on the path to mass-market printing. They raised issues about the symbolic power of the printing press, the role of master craftsmen, and the changing nature of gendered work.

제어냉각 장치를 이용한 엔진피스톤 열간단조 공정에 관한 연구

Abstract The piston engine is an essential component in automobiles. Since the piston is used in a high temperature and high pressure environment, the piston needs to be manufactured to achieve high strength and high durability. In addition, cost reduction is also an important consideration. In conventional forging, an additional heat treatment after hot forging is necessary to ensure proper mechanical properties for heavy-duty engine pistons. The newly developed manufacturing method lowers production costs by saving manufacturing time and reduces energy consumption. The current paper describes the hot forging of an engine piston made from 38MnSiVS5 micro-alloyed steel using controlled cooling. The finite element analysis was used to check for possible problems and suitable press capacity. Hot forging experiments were then conducted on a 2500tons crank press to evaluate feasibility of the proposed material and process. To check the mechanical properties after hot forging, the forged specimens were tensile tested, and the microstructures were examined in order to compare the results with the conventionally forged material. The skirt region of the as-forged 38MnSiVS5 piston showed better material properties compared to the conventional material. In addition, the total production time was reduced by about 80% as compared to conventional forging.

유한요소해석을 통한 컵형상 대형단조품의 성형공법 설계

This research developed a new deep-bore, cup-shape, large forging process by combining die forging and free forging methods. In the proposed process, a preform for cup-shape large forging is produced by die forging, and a product with a deep bore is finally manufactured using an open die forging method, which is generally produced using a backward extrusion process. Finite element analysis results showed a higher effective strain distribution with a smaller forging load using the proposed method compared to the backward extrusion method. The production of a prototype with good internal quality using a small press capacity verified the proposed method.

Optimization of Preform Die Shape for Forging AA2017 Turbine Disk Using Electrostatic Field Theory

Equipotential lines were used to optimize the shape of a preform die for producing aluminum alloy (AA2017) turbine disks. The optimization criteria were complete filling, reduced forging loads and uniform effective plastic strain. Using the optimal preform die identified by the adopted optimization method, the maximum and minimum effective plastic strains were increased from 1.09 and 0.1562 to 1.429 and 0.218, respectively. Moreover, the required forging force was reduced from 3.12 to 2.58 E4 kN. This shows that the preform die reduced the maximum press capacity required to forge the disk. It also produced good results in terms of full filling and the absence of dead zones, which were evidenced by the die contact.