곡률압출공정을 이용한 알루미늄 Bumper Back Beam 개발

이상곤(Sang-Kon Lee),조영준(Young-June Jo),김병민(Byung-Min Kim),박상우(Sang-Woo Park),오개희(Kae-Hee Oh) 대한기계학회 2009 大韓機械學會論文集A Vol.33 No.5

Curvature extrusion process has several advantages in comparison to the conventional extrusion and bending process. In the curvature extrusion, the extruded part is directly bent during extrusion. Therefore, it does not need additional bending process after extrusion. In the curvature extrusion process, it is possible to produce curved extruded products that have a constant or various curvatures. It is essential that we predict the curvatures of the extruded product to meet the required curvatures. This paper proposed a theoretical model that can predict the curvature of extruded product produced by the curvature extrusion process. Using the proposed model the movement of guide tool that causes the bending of extruded product was controlled to produce the required curved automotive Al bumper back beam. The effectiveness of the proposed prediction model and the movement of guide tool were verified by the FE analysis and curved extrusion experiment.

노후 압출기의 재제조를 위한 고장모드 영향분석

정항철(Hang-Chul Jung),윤상민(Sang-Min Yun),오상호(Sang-Ho Oh),백창현(Chang Hyun Baeg),공만식(Man-Sik Kong) 한국청정기술학회 2021 청정기술 Vol.27 No.4

국내 알루미늄 산업에서 압출공정은 생산량 기준 40% 이상의 비중을 차지하고 있는 주요 공정이다. 국내 알루미늄 압출업체 대부분이 30년 이상 된 노후 설비를 이용하여 생산하고 있기 때문에 제품 정밀도 및 품질 저하, 낮은 생산성 등의 문제를 격고 있다. 압출 설비는 한번 도입하면 주요 부품의 마모 또는 파손 발생 전에는 설비를 교체하지 않는 구조로 신규 설비에 비해 생산성 감소 및 불량률이 증가하기 때문에 설비의 유지 관리가 중요하다. 노후 압출기는 부품의 도면이 소실된 경우가 많아 현장에서 적절한 보수가 어렵고 유지 관리를 위한 기술력 부재로 인해 재제조에 어려움을 겪고 있기 때문에 해체 단계에서부터 체계적인 재제조 방안이 고안되어야 한다. 본 연구에서는 노후 압출설비의 재제조를 위해 재제조 고장모드 영향분석 방법을 고안하였다. 부품에 대한 재제조 대상 부품의 파손에 대한 심각도, 압출 공정 중 고장/파손에 따른 수명 그리고 재제조에 따른 자원순환의 가치를 고려하여 위험우선순위를 산정하고 재제조 대상을 선정하였다. 노후 압출기의 재제조 공정의 표준화 정립을 위해 노후 압출기의 구조에 따른 모듈 및 부품에 대한 분석 등을 통해 재제조 고장모드 영향분석을 수행하였으며 부품별 우선순위를 선정하여 자원순환의 효율성 및 제품 품질 안정화를 위한 재제조 연구를 수행하였다. In the domestic aluminum industry, the extrusion process is a major process accounting for more than 40% of the total production. However, most domestic aluminum extrusion companies produce aluminum using old equipment that is more than 30 years old. Extrusion press is when the equipment is not replaced before the wear and breakage of major parts occur, reducing productivity and increasing the defect rate compared to new equipment. The old extrusion press often loses part drawings, so it is difficult to repair them properly on-site and to remanufacture them due to the lack of technical skills for maintenance. Therefore, a systematic remanufacturing plan must be designed from dismantling the equipment. In this study, remanufacturing FMEA was devised to remanufacture old extrusion press. The risk priority was analyzed by considering the degree of damage to the recycled parts, the cycle due to breakage/damage during the extrusion process, and the value of recycling resources due to remanufacturing. To standardize the remanufacturing process, remanufactured FMEA was performed through part analysis according to the structural analysis of the extrusion press. In addition, remanufacturing priorities were selected for each part, while remanufacturing itself was studied for efficiency of resource circulation and product quality stabilization.

온도 유지시간 제어를 적용한 하이브리드 분말 압출 공정을 통한 요구 특성의 스퍼기어 제조

이경훈(Kyung Hun Lee),황대원(Dae Won Hwang),김병민(Byung Min Kim) 대한기계학회 2011 大韓機械學會論文集A Vol.35 No.8

본 연구는 압출 시 성형온도를 유지하여 Zn-22Al 합금분말의 성형성을 향상시키는 하이브리드 분말 압출 공정의 개발 및 온도 유지시간이 압출된 스퍼기어의 기계적 특성에 미치는 영향을 조사하기 위해 수행되었다. 피치원 지름 1.8mm 의 소형 스퍼기어는 압출온도 290, 300, 310℃에서 성형되었다. 볼밀시간 32h 의 Zn-22Al 합금분말을 압출온도 310℃에서 압출 시 표면 결함이 없는 소형 기어가 제조되었다. 경도분포는 기어 중심부와 치형부에서 불균일하였고 소결공정 후 내부 변형에너지의 차이로 인해 내부균열이 발생하였다. 위와 같은 문제를 해결하기 위해 온도 유지시간 제어를 이용한 하이브리드 압출 연구를 수행하였다. 압출된 스퍼기어의 평가는 압출하중, 비커스 경도 및 치수정밀도 측정을 통해 이루어졌다. 온도 유지시간 15min 에서 압출된 스퍼기어의 기계적 성질이 가장 우수하였다. In this study, a hybrid powder-extrusion process involving the control of temperature dwelling time for improving the formability of Zn-22Al powder was developed and the effect of dwelling time on the mechanical properties of a spur gear with a pitch circle having a diameter of 1.8 mm was investigated. General extrusion experiments were carried out at different temperatures such as 290, 300, and 310°C. Spur gears with good qualities and without any surface defects were obtained in the case of extrusion temperature of 310°C and ball-milling duration of 32 h. The Vickers hardness distribution was non-uniform, and after the sintering process, an internal crack was generated because of the different deformation energy between gear central part and teeth. To overcome the abovementioned problems, research on controlling the dwelling time of the extrusion temperature in the powder-extrusion process was carried out. Good-quality spur gears were obtained when the dwelling time was 15 min.

고분자압출성형용 Single-Screw에 관한 열유동 기초연구

정효희,김재열,고명석,최승현,심재기,한재호 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

Extrusion Screw, point parts of extrusion molding extruder, is expanded widely use area with construction machinery, site conveyance device food processor, medicine as well as Polymer extrusion forming. Because this can expect large quantity demand about Screw of special quality of extrusion Screw item, is become processing industry that adopt all kinds of small quantity production type. Accordingly, analysis by extrusion screw is also consisting of several directions. Extrusion screw differentia is appeared much at material selection of screw itself and each screw design as parts that cause a lot of high temperature and high tension and attrition among processing of product and use purpose and that should do it so that working conditions back according to kind of used balance may optimize of each Screw are desirable. In this treatise, analyzed and analyze single-screw that is using developing in Human Resource Training Project for regional Innovation subject considering pressure, temperature etc.. of extrusion screw using CFdesign that is 3 dimensional analysis program.

역압출 수치 해석을 이용한 마이크로 카테터 압출 다이 설계에 관한 연구

홍성근,전원진,김우진,이은택 한국전산유체공학회 2023 한국전산유체공학회지 Vol.28 No.4

This study represents design method of extrusion die for micro catheter manufacturing with inverse extrusion. The inverse extrusion can predict the geometry of the die required to achieve the target profile of the extrudate. Peripherally inserted central catheter is used for many medical applications and has various geometries. In this study, the design of the die for peripherally inserted central catheter with 2 lumens is investigated. The geometries of the die are predicted to obtain the extrudate with the various thickness of the outer and middle wall of the tube. The velocity distribution of the molten polymer at the end of the die exit and the thickness ratio of the die according to the thickness ratio of the target profile are examined. The correlations between the thickness ratio of the target and the geometry of the predicted die are identified. The inverse extrusion and correlation are useful to design the geometry of the die for the desired profile of the extrudate.

정수압 압출을 이용한 Copper-clad Aluminum 복합재 제조에 대한 연구

한운용(Woon Yong Han),이경엽(Kyong Yop Rhee),박훈재(Hoon Jae Park),윤덕재(Duk Jae Yoon),김승수(Seung Soo Kim) Korean Society for Precision Engineering 2004 한국정밀공학회지 Vol.21 No.7

In this work, a copper-clad aluminum composite was fabricated using hot hydrostatic extrusion with various extrusion ratios (8.5, 19, 49) and semi-die angles (30, 45, 60 degree) at a temperature of 320℃. Material characteristics of copper-clad aluminum composites were determined from compression tests and hardness tests. The results showed that for ER of 8.5, the optimum semi-die angle was below or equal to 30 degree and a pressure drop was about 31 %. For ER of 19, the optimum semi-die angle was in the range of 40 to 50 degree and a pressure drop was about 38%. In the case of ER=49, the optimum semi-die angle was above or equal to 60 degree and a pressure drop was about 36%. Compressive yield strength was maximum for ER of 8.5 and semi-die angle of 30 degree and the value of maximum was 155 ㎫. Uniform hardness distribution was obtained as the extrusion ratio increases and the semi-die angle decreases. In the case of ER=8.5 and semi-die angle of 30 degree, the lowest extrusion pressure and the maximum comperssive yield strength was obtained. Therefor, it was concluded that the optimum extrusion condition for fabricated copper-clad aluminum composites under hydrostatic pressure environment was ER of 19 and semi-die angle of 30 degree.

열가소성고분자 압출성형 시스템 개발 및 기초연구

김재열(JaeYeol Kim),정효희(HyoHee Jung),고명석(MyungSeok Ko),최승현(SeungHyun Choi),최진호(JinHo Choi),김종문(JongMun Kim),홍철(Cheol Hong) 한국트라이볼로지학회 2008 한국트라이볼로지학회 학술대회 Vol.2008 No.6

Have preserved perfectly polymer raw material of solid state or High horoscope at process at extrusion process and try much to heighten precision of raw material supply and processing perfectly. It is extrusion Screw and temperature pressure control system been hopper system and the most important parts among parts used at extrusion process. In printer roller incrustment development that is main target of system development applying system developed in research that serve that a lot of problems appear and supplements the problem in each system in case of operate extrusion system using heat range plasticity raw material among polymer raw material thus to extrusion molding system that use thermoplasticity polymer raw material correct and quantitative target achievement possibility will be done and will produce epoch-making and stable product in extrusion process that uses thermoplastic polymer raw material.

단축스크류 고분자압출기 시스템의 개발 및 성능평가

김재열(Jae Yeol Kim),정효희(HyoHee Jung),최승현(SeungHyun Choi),최진호(JinHo Choi),김종문(JongMun Kim) 한국트라이볼로지학회 2008 한국트라이볼로지학회 학술대회 Vol.2008 No.11

Can divide into bisk kind extruder and screw extruder if divide greatly extruder by basic. To use to pump that carry water and oil as plastic extrusion simplicity of utilization be but thing which is used most these day is screw extruder. Use of screw is using at a lot of extrusion processes. Extrusion process is becoming use that is much in complex processing and process to charge shape or form of various material with, plastic material, medicine material, food material, polymer composite material, iron and ceramics powder material etc. Also, because material correction of deformities by flow and physicochemical reaction phenomenon according to heat transfer and so on of material at extrusion process is available, become fearful. And various material comes to hopper because extruder has function by blender and mixing of materials can go well before come out through dice. These change process is so complicated that process condition is decided by trial and error that process condition is underground mainly at extrusion molding process.

A7003 합금의 환경친화적 압출공정을 위한 Mg조성 및 공정비교 연구

조훈,조형호,한명근,김영직 한국전과정평가학회 2002 한국전과정평가학회지 Vol.4 No.1

최근 수송기계 경량화 추세에 부응하여 door impact beam, seat side rail 및 hood support와 같은 자동차 부품등에 Al-Mg-Zn계 중경질 A7003 합금소재의 적용이 검토되고 있는 실정이다. 그러나 이들 합금소재의 적용을 위해서는 제품의 용도와 특성을 만족함과 동시에 압출성이 높은 합금소재의 개발이 선행되어야 한다. 본 연구에서는 A7003 합금소재의 압출성을 향상시키기 위하여 합금원소 첨가량이 미세조직, 압출성 및 기계적 특성에 미치는 영향을 조사하였다. Mg조성 제어에 의해 기계적 강도의 저하없이 A7003 합금의 압출성을 향상시킬 수 있었다. 또한 MLCA 기법을 적용하여 A7003 합금중의 Mg 첨가량 및 빌렛가열공정 변화에 따른 에너지 소비량 및 환경오염부하물질 배출량을 산정하였다. A7003 합금중 Mg의 첨가량을 제어하여도 압출재 생산에 소요되는 에너지의 소비량은 거의 같음을 확인하였으며 CO₂와 같은 대기오염물질을 저감시키기 위해서는 유도가열에 의한 빌렛가열공정의 적용이 가장 효과적임을 알 수 있었다. A7003 alloy has characteristics of their excellent weldability, high corrosion resistance and superior plastic working however the broadening of application for the alloy has been hampered by the lower extrudability associated by Mg content. For improvement of extrudability and enhanced recovery efficiency during Al scrap recycling, it has been generally practiced to reduce Mg content in A7003 alloy. Therefore, it is necessary to investigate the influence of Mg content on mechanical strength and extrudability of A7003 alloy. For efficient material processing which has small amounts, material life cycle assessment(MLCA) is evaluated. The quantitative analysis of energy requirements and CO₂ emission for production of A7003 extruded bar are estimated with different Mg content and billet pre-heating process (heating source by light oil or LPG). In particular, the estimation of energy requirements was performed within shipping and gating range (except the mining and extraction stages) to investigate the influence of the variables on energy requirements and CO₂ emission in detail. As Mg content increased, the flow stress and the extrusion pressure for A7003 alloy increased. It has been thought that an increment in extrusion pressure with increasing Mg content is caused by the solid solution hardening of Mg atoms in the matrix and increment in volume fraction of intermetallic compound, Mg2Si. The extrudability and the tensile strength are equal to, or above that of conventional A7003 alloy even the content of Mg varied from 1.1wt.% to 0.5wt.%.alloy. This means that minimizing the content of Mg in A7003 alloy can enhance recovery efficiency during Al scrap recycling. It can be quoted that rather than Mg content energy source for billet heating is a prime factor to determine the atmospheric CO₂ emission.

유한요소법을 이용한 냉간 개방 압출 공정의 성형 한계 예측

Qiu Yuangen,박승철(Seung Chul Park),조해용(Hae Young Cho) 대한기계학회 2020 大韓機械學會論文集A Vol.44 No.6

냉간 개방 압출은 소재의 일부는 금형에 구속시키고 나머지는 금형 밖으로 노출시킨 후 압출하는 금속성형법이다. 과도한 단면 감소율로 냉간 개방 압출 시 베럴링 결함이 발생할 수 있다. 베럴링 결함이 발생하지 않는 최대 단면 감소율을 성형 한계라 한다. 볼트와 같은 체결용 부품은 다단 단조 공정을 통해 생산된다. 생산 효율을 높이고 생산 비용을 줄이기 위해 다단 단조 공정의 단수를 줄여야 한다. 이를 위해 성형 한계가 요구된다. 따라서 본 연구에서는 상용 유한요소 해석 프로그램은 DEFORM-3D를 이용하여 설계 변수에 따른 냉간 개방 압출 시뮬레이션을 하였고, 실험과 비교 및 분석하여 냉간 개방 압출 공정의 성형 한계를 제시하였다. The open-die extrusion is performed in state the billet is not entirely guided in the die. Cold open-die extrusion of Excessive reduction of area causes barreling defects. The maximum reduction of area at which no barreling defects occur is called the forming limit. Fasteners such as bolts are produced through a multi-stage forging process. In order to increase production efficiency and reduce production cost, the number of stages of multi-stage forging process should be reduced. Therefore, forming limits are required. In this thesis, predictions of forming limits in cold open-die extrusion process has been simulated by using commercial FEM code DEFORM-3D. the simulated results were compared with experimental ones.