• 제목/요약/키워드: Die Shape Radius

검색결과 60건 처리시간 0.046초

프레스 포밍 공정을 이용한 피팅 파이프 성형 조건 선정 (Determination of Forming Conditions of Fitting Pipes using Press Forming Processes)

  • 김태걸;박영철;박경용
    • 한국기계가공학회지
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    • 제11권1호
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    • pp.101-106
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    • 2012
  • The press bulging process is very useful and productive method to produce round-type mechanical components which have not been able to be manufactured because of limitation of the conventional press technology. The application of the press bulging process has expanded very quickly in the hydraulic and electronic industry and more recently it has been used to produce other mechanical parts such as the automobile and shipping parts. This expanding application also has brought some unsolved problems and leads many researchers to put their effort into the die design of the press bulging process. In this study, to obtain the optimum die shape for the press bulging process, various process parameters have been considered such as corner radius, bulging height, pressing length, and forming load, etc. The main interest of this paper is to verify the press bulging process which has more than 4.0 in height-length ratio. From this aspect, Finite Element analysis shows great ability to simulate the precise deformation process and gives us manufacturing database. Consideration of strain, stress, and strain-rate for the various cases has been also taken to keep the forming load within a particular range.

평형해법에 의한 스탬핑 공정의 단면 해석 (Sectional analysis of stamping processes using Equilibrium approach)

  • 윤정환;유동진;송인섭;양동열;이장희
    • 한국정밀공학회지
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    • 제11권4호
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    • pp.58-68
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    • 1994
  • An equilibrium approach is suggested as an effective tool for the analysis of sheet metal forming processes on the basis of force balance together with geometric relations and plasticity theroy. In computing a force balance equation, it is required to define a geometric curve approximating the shape of the sheet metal at any step of deformation from the geometric interaction between the die and the deforming sheet. Then the geometic informations for contacting and non-contacting sections of the sheet metal such as the number and length of both non-contact region, contact angle, and die radius of contact section are known from the geometric forming curve and utilized for optimization by force balance equation. In computation, the sheet material is assumed to be of normal amisotropy and rigid-phastic workhardening. It has been shown that there are good agreements between the equilibrium approach and FEM computation for the benchmark test example and auto-body panels whose sections can be assumed in plane-strain state. The proposed equilibrium approach can thus be used as a robust computational method in estimating the forming defects and forming severity rather quickly in the die design stage.

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AZ31B 마그네슘 합금 판재에 대한 드로우벤드 시험과 스프링백 측정 (Measurement of Springback of AZ31B Mg Alloy Sheet in Draw/bend Test)

  • 최종길;이명규;김헌영
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 춘계학술대회 논문집
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    • pp.302-305
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    • 2007
  • The springback characteristics of AZ31B magnesium alloy sheet was investigated in OSU draw/bend test. Springback is the elastically-driven change of shape of a part after forming and it should be estimated and controlled to manufacture more precise products in sheet forming. The demands are increasing for magnesium alloy sheet press forming, but the study on its springback characteristics is insufficient. Strip draw/bend tests were conducted with various conditions - die radius, sheet thickness and controlled tensile force. The springback angles were measured from 'sidewall curl' of deformed shape. The tendency of springback angle was observed from the tests.

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레이저 열-압착 본딩 시스템의 Lateral Force 감소를 위한 유연 힌지의 설계 (Design of flexure hinge to reduce lateral force of laser assisted thermo-compression bonding system)

  • 이동원;하석재;박정연;윤길상
    • Design & Manufacturing
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    • 제14권3호
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    • pp.23-30
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    • 2020
  • Laser Assisted Thermo-Compression Bonding (LATCB) has been proposed to improve the "chip tilt due to the difference in solder bump height" that occurs during the conventional semiconductor chip bonding process. The bonding module of the LATCB system has used a piezoelectric actuator to control the inclination of the compression jig on a micro scale, and the piezoelectric actuator has been directly coupled to the compression jig to minimize the assembly tolerance of the compression jig. However, this structure generates a lateral force in the piezoelectric actuator when the compression jig is tilted, and the stacked piezoelectric element vulnerable to the lateral force has a risk of failure. In this paper, the optimal design of the flexure hinge was performed to minimize the lateral force generated in the piezoelectric actuator when the compression jig is tilted by using the displacement difference of the piezoelectric actuator in the bonding module for LATCB. The design variables of the flexure hinge were defined as the hinge height, the minimum diameter, and the notch radius. And the effect of the change of each variable on the stress generated in the flexible hinge and the lateral force acting on the piezoelectric actuator was analyzed. Also, optimization was carried out using commercial structural analysis software. As a result, when the displacement difference between the piezoelectric actuators is the maximum (90um), the maximum stress generated in the flexible hinge is 11.5% of the elastic limit of the hinge material, and the lateral force acting on the piezoelectric actuator is less than 1N.

커먼레일 파이프 헤딩공정의 접힘결함 방지에 관한 연구 (A Study for Preventing Folding Defect of the Common Rail Pipe in Heading Process)

  • 송명준;우타관;정성윤;허관도;김철
    • 한국정밀공학회지
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    • 제27권1호
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    • pp.25-32
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    • 2010
  • With the latest automobile technology, though the third generation common rail system requires high injection pressures up to 1,800bar, the next generation diesel engine is expected to require more higher pressures than the third generation. The common rail pipe requires higher strength because it is one of the parts in the common rail system, which is influenced directly by fuel under high pressure. Preform design is very important for preventing head of the common rail pipe from folding in the heading process. In this study, die angle, curvature, outer diameter of die and length of trapped part are selected as main parameters to obtain best preform shape minimizing radius of folding. Therefore optimal design is carried out by finite element analysis and Taguchi method through main parameters. Results of the finite element analysis have good agreements with those of the experiments in the actual field.

니켈합금 Alloy42를 사용하는 리드프레임의 블랭킹 특성에 관한 기초연구 (A Study on the Characteristics for the Blanking of Lead Frame with the nickel alloy Alloy42)

  • 반갑수;서의권;이광호;모창기
    • 한국공작기계학회논문집
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    • 제13권6호
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    • pp.87-93
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    • 2004
  • An experimental is carried out to investigate the characteristics of blanking for nickel alloy Alloy42 (t=0.203mm), a kind of IC lead frame material. By varying clearance between die and punch the shapes of shear profile are examined. Finite element analysis with element deletion algorithm for ductile fracture mode is also carried out to study the effect of clearance theoretically and to compare with experimental results. The rectangular shape specimen with four different comer radius is used to study the characteristics of blanking for straight side and comer region simultaneously. As the result the ratios measured k(m experiment of roll over, burnish and fracture zone based on initial blank thickness are compared with those of FE analysis. Both experiment and FE analysis show that the amount of mil over and fracture is increased as the clearance increases. When the radius of comer is less than thickness of blank it has been found that larger clearance is required than that of straight region in order to maintain same quality of shear profile at the comer region.

스테인리스 강 STS305의 디프 드로잉 가공에 관한 실험적 연구 (Experimental study on the severe deep drawing for complex cylindrical housing of STS 305 stainless steel)

  • 김두환
    • 소성∙가공
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    • 제7권5호
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    • pp.439-444
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    • 1998
  • Recently many automotive parts have been made with stainless steels by deep drawing processes, But there are various problems occurred in deep drawing works of stainless steels compared with low carbon steels. For the severe deep drawing of complex cylindrical housing optimum process planning is required to eliminate intermediate annealing improve shape accuracy and maintain surface integrity without drawing defects such as tears wrinkles and scratches or galling. Therefore in this study a sample process planning of the severe of the severe deep drawing process is applied to a complex cylindrical housing needed for a 6 multi-stepped deep drawing of type STS 305 . A series of experiments are performed to investigate optimum process variables such as drawing rate radius and clearance. Through experiments the variations of the thickness strain distribution and hardness distribution in each drawing step are observed. Also the effects of other factors on formability such as drawing oil, blank holding force and die geometry are examined and discussed.

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퍼스널 컴퓨터에 의한 디이프드로잉 공정설계의 전산화에 관한 연구 (I) (A Study on the process planning of Deep drawing using personal computer)

  • 최재찬;진인태
    • 한국정밀공학회지
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    • 제5권3호
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    • pp.31-42
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    • 1988
  • This paper describes a computer aided process planning system called "Deep-Drawing", "Deep-Drawing" is designed for the drawing sequence of cylindrical and rectangular cups with or without taper and flange. The computer program has written in BASIC language with personal computer. Design Rules for process planning are formulated from process limitation, plasticity theory and experimental results including the know-how of many manufacturing factories. "Deep-Drawing" Capabilities include the analysis of drawing sequence by the determination of optimal drawing ratio, the determination of intermediate shape, dimensions, punch and die radius etc., the calculation of drawing loads and blank holder force to perform each drawing step, and the graphic outputs for the operation sheet.tputs for the operation sheet.

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외연적 유한요소법을 이용한 세장비가 큰 타원형 컵 성형공정의 다단계 해석 (Multi-stage Analysis of Elliptic Cup Drawing Processes with the Large Aspect Ratio by an Explicit Elasto-Plastic Finite Element Method)

  • 김세호;김승호;허훈
    • 소성∙가공
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    • 제9권3호
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    • pp.313-319
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    • 2000
  • Finite element analysis is carried out for simulation of the multi-stage elliptic cup drawing process with the large aspect ratio. The analysis incorporates with shell elements for an elasto-plastic finite element method with the explicit time integration scheme. For the simulation, LS-DYNA3D is utilized for its wide capability of solving forming problems. The simulation result shows that the non-uniform drawing ratio at the elliptic cross section ad the small shoulder radius cause failure such as tearing and wrinkling. The result suggests the guideline to modify the tool shape for prevention of the failure during the drawing process.

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AZ31B 마그네슘 합금 판재의 OSU 드로우벤드 시험과 스프링 백 측정 (Measurement of Springback of AZ31B Mg Alloy Sheet in OSU Draw/bend Test)

  • 최종길;최선철;이명규;김헌영
    • 소성∙가공
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    • 제16권6호
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    • pp.447-451
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    • 2007
  • The springback characteristics of AZ31B magnesium alloy sheet was investigated in OSU draw/bend test Springback is the elastically-driven change of shape of a part after forming and it should be estimated and controlled to manufacture more precise products in sheet forming. Magnesium alloy sheets have unique mechanical properties such as high in-plane anisotropy/asymmetry of yield stress and hardening response. So, there will be a difference in the prediction of springback with symmetric mechanical properties for magnesium alloy sheets. In this work, the Strip draw/bend tests were conducted with various conditions - die radius, sheet thickness and controlled tensile force and the tendency of springback angle was observed from the tests.