롤 포밍 공정에서의 롤 패스의 수에 따른 스프링 백 영향 연구

김동홍(Dong-Hong Kim),장애(Ya Zhang),정동원(Dong-Won Jung) 한국기계가공학회 2016 한국기계가공학회지 Vol.15 No.1

This study was analyed V-bending in order to analyze the spring-back phenomenon in the roll forming process. The material of forming sheet used in the roll forming process is high tension steel and the product name of sheet material is POSTEN 60. The most important variable is the number of roll passes (3-Pass, 4-Pass, 5-Pass, 6-Pass and 10-Pass) and other roll forming process variables were fixed. To determine the characteristics of the tension and compression, the forming sheet was analyzed by dividing the layer (Upper and Bottom) in the thickness direction from the center line. The results of FEM simulation analysis was derived to von-mises stress equivalent strain, and the spring-back value was calculated according to the final forming shape. The more number of the roll pass, von-mises stress and equivalent strain value of forming sheet were lowed. Also, spring-back values tended to decrease. The results of this study can be utilized for prediction and trend of spring-back value in the roll forming process applied to high tension steel sheet. So, development time and cost of the roll forming process is expected to be reduced.

강소성 유한 요소법을 이용한 냉간압연강판의 성형 롤 설계

정상화(Sang-Hwa Jeong),이상희(Sang-Hee Lee) 한국기계가공학회 2007 한국기계가공학회 춘추계학술대회 논문집 Vol.2007 No.-

Roll forming is the effective process used to manufacture long sheet metal products with constant cross section. Roll forming process is very important in many industries because it is possible to manufacture a section just like tube, channel and angle. However, it is difficult because much time and money are needed to find defects. In order to overcome this difficulty, computational analysis method is developed for roll forming process. In this paper, the under rail composed of three members is designed and the roll forming process is simulated. It is a relatively unsophisticated mechanism that has rectilinear reciprocating motion. A flow stress equation on the cold rolled carbon steel sheet(SCP-1) is set up by doing the tensile test. The flower pattern of the upper member in the under rail is designed as two types and the roll forming process is estimated by using SHAPE-RF software. The longitudinal strain and the magnitude of camber and bow are predicted from the results of the simulation. Besides, The qualities of the final product formed by two types of flower pattern are compared.

롤 포밍 공정에서의 길이방향 변형률 및 직진성 예측

정상화(Sang-Hwa Jeong),이상희(Sang-Hee Lee) 한국기계가공학회 2007 한국기계가공학회 춘추계학술대회 논문집 Vol.2007 No.-

Cold roll forming can be described basically as a process where a metal sheet is continuously formed in the transverse direction into a product with a desired cross-sectional profile by passing a series of pairs of forming rolls. However, process analysis is very difficult because deformation procedures are quite complex and have many variable. The cold-roll forming has been mostly developed through the experimental knowledge. In order to overcome this difficulty, the roll forming process for manufacturing the under rail is analyzed using a new computational method based on the rigid-plastic finite element. In this paper, the roll forming process of the lower member at under rail is simulated using simulation software. Tensile test is performed about SCP-1 to obtain material properties and curve fitting is executed to set up the flow stress equation. The lower member is designed using the constant arc length forming method and the constant radius forming method for excellent design. The longitudinal strain is estimated on the basis of simulation results. In addition, the numerical magnitudes of camber and bow are predicted from the results of the simulation

FEM을 이용한 롤 포밍 공정의 3차원 모델링

정상화(Sang Hwa Jeong),이상희(Sang Hee Lee) 한국생산제조학회 2007 한국공작기계학회 춘계학술대회논문집 Vol.2007 No.-

Cold-roll-forming (CRF) is a well known process used to manufacture long sheet metal products with a constant cross section. It can manufacture goods of the uniform cross section on a large scale as a continuous processing. Also it is a very important process in many industrial fields to increase of the application. However, product design procedures, in terms of rolls design and rolls pass schedule, remain rather an art than science. Therefore, many times and money are needed for manufacturing goods. In order to overcome this difficulty, a new computational method based on the rigid-plastic finite method is developed for the analysis of roll forming process and the optimum design. Analysis using FEM(Finite Element Method) and FDM(Finite Difference Method) is used in the deformation analysis. In this paper, to make lower member for under rail roll using FEM simulation software(SHAPE-RF), the roll forming 3-D modeling and simulation are performed, Tensile test is performed about SCP-1 for input properties to program. Besides, curve fitting is executed to set up the flow stress equation. Final shape is predicted after 11-pass. The longitudinal strain is estimated on the basis of simulation result. In addition, Bow and Camber which is one of the several defects are measured.

언더레일 성형을 위한 롤포밍 공정 설계

정상화,이상희 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

Roll forming process is one of the most widely used processes in the world for forming metals. It can manufacture goods of the uniform cross section throughout the continuous processing. However, analysis of process is very difficult because of the inherent complexity of the process. For this reason, the computer analysis methods such as the FEM(Finite Element Method) and the FDM(Finite Difference Method) are frequently used in roll forming design. In this paper, the under rail composed of upper member, center member and lower member is modeled. Also the flower pattern of the upper member is designed and the roll forming process is simulated. The upper member is designed using constant arc length forming method and constant radius forming method for excellent design. The cold rolled carbon steel sheet(SCP-1) is used in this simulation, and a flow stress equation is set up through the tensile test. Each types are simulated and compared with the longitudinal strain using SHAPE-RF software. In addition, the numerical magnitude of camber and bow are predicted from the results of the simulation.

Smart Roll Forming Based on Real-Time Process Data

Jae-Hwan Son(손재환),Dong-Hyun Cho(조동현),Chul-Hong Kim(김철홍) 한국기계가공학회 2018 한국기계가공학회지 Vol.17 No.5

Roll forming refers to the production of long plate-molded products, such as panels, pipes, tubes, channels, and frames, by continuously causing the bending deformation to thin plates using rotating rolls. As the roll forming method has advantages in terms of mass production because of its excellent productivity, the size of the roll forming industry has been continuously increasing and the roll forming method is increasingly being used in diverse industrial fields as a very important processing method. Furthermore, as the roll forming method mainly depends on the continuous bending deformation of the plate materials, the time and the cost of the heterogeneous materials developed in the process are relatively large when considered from the viewpoint of plastic working because many processes are continuously implemented. The existing studies on roll forming manufacturing have reported the loss of large amounts of time and materials when the raw materials or product types were changed; further, they have stated that the use of this method can hardly guarantee the uniformity of the formed shapes and the consistency in terms of size and cannot detect all the defects occurring during the mass production and related to the dimensions. Therefore, in this research, a real-time process data-based smart roll forming method that can be applied to multiple products was studied. As a result, a roll forming system was implemented that remembers and automatically sets the changes in the finely adjusted values of the supplied quantities of individual heterogeneous materials so that the equipment setting changing time for heterogeneous material replacements or changes in the products being produced can be shortened. It also secures the uniformity of the products so that more competitive and precise slide-rail products can be mass-produced with improvements in the quality, price, and productivity of the products.

롤포밍 공정에서의 성형방법에 따른 직진성 예측

정상화,이상희,김재상,박진완,임성빈 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.2

Roll forming process is one of the most widely used processes in the world for forming metals. It can manufacture goods of the uniform cross section throughout the continuous processing. However, analysis of process is very difficult because of the inherent complexity of the process. For this reason, the computer analysis methods such as the FEM(Finite Element Method) and the FDM(Finite Difference Method) are frequently used in roll forming design. In this paper, the under rail composed of upper member, center member and lower member is modeled. Also the flower pattern of the upper member is designed and the roll forming process is simulated. The upper member is designed using constant arc length forming method and constant radius forming method for excellent design. The cold rolled carbon steel sheet(SCP-l) is used in this simulation, and a flow stress equation is set up through the tensile test. Each types are simulated and compared with the longitudinal strain using SHAPE-RF software. In addition. the numerical magnitude of camber and bow is predicted from the results of the simulation.

언더레일의 롤포밍 공정 시뮬레이션에 관한 연구

정상화(Sang Hwa Jeong),이상희(Sang Hee Lee),김광호(Gwang Ho Kim),김재상(Jae Sang Kim),김종태(Jong Tae Kim) 한국생산제조학회 2008 한국생산제조학회지 Vol.17 No.3

Roll forming process is one of the most widely used processes in the world for forming metals. It can manufacture goods of the uniform cross section throughout the continuous processing. However, process analysis is very difficult because of the inherent complexity. Therefore, time is consuming and much money are needed for manufacturing goods. In order to overcome this difficulty, a new computational method based on the rigid-plastic finite element method is developed for the analysis of roll forming process. In this paper, the design of roll forming process and the simulation are performed to manufacture the upper member at under rail composed of three members. The cold rolled carbon steel sheet(SCP-1) is used in this simulation, and a flow stress equation is set up by conducting the tensile test. The upper member is designed using two types of design for a excellent design. Each types are simulated and compared with the strain distribution using SHAPE-RF software. In addition, the numerical magnitude of bow and camber which are the buckling phenomenon is estimated.

3점 언더레일 슬라이드의 롤포밍 공정에 대한 성형해석연구

정동원(D. W. Jung),박상후(S. H. Park),정지현(J. H. Jeong) 한국동력기계공학회 2012 동력시스템공학회지 Vol.16 No.6

식기세척기용 Under Rail Roll Forming 금형 개발을 위한 강소성 유한요소 해석

정상화(Sang-Hwa Jeong),이상희(Sang-Hee Lee),김광호(Gwang-Ho Kim),신상문(Sang-Moon Shin),김주환(Ju-Hwan Kim) 한국기계가공학회 2006 한국기계가공학회 춘추계학술대회 논문집 Vol.2006 No.-

The slide rail is the latest device driven by rectilinear reciprocating motion. It is used for the great deal of fields with the progress of high technology in these days: for example, telecommunication device, measurement device, copy machine, refrigerator, car, office furniture and wood furniture, ect.. But it is very difficult to produce the press mold that has a forming of narrow thickness, straight quality and high accuracy. Recently Roll forming technique is used to fabricate the slide rail. To evaluate the characteristics of each path shape is not easy because the roll forming passes the sheet metal in the continuously arranged multistage roll stands. In this paper, Roll forming simulation is performed to make U-channel using SHARP-RF. Longitudinal strain and total effective strain are evaluated. In addition, Springback is measured about each bending part of upper.