• 대한기계학회논문집A
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• 제31권7호
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• pp.800-807
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• 2007

Autofrettage process is used for internal forming and sizing of cylinder designed to withstand high internal pressures. Once the tube is autofrettaged, it needs to be machined to its final dimensions both at the bore and its outer surface. This paper presents an analytical analysis and numerical analysis of machined compound cylinder using finite element code, ANSYS10.0. An analytical model for predicting the level of autofrettage following either inner, outer, or combined machining of the compound cylinder is developed for the autofrettage residual stress field is simulated by an autofrettaged pressure. The autofrettaged pressures are obtained by using trying-error method. As autofrettage percentage is 20 % and 40 %, the numerical results are found to be in almost agreement with the analytical ones. However, as autofrettage percentage is 60 %, the numerical results have a little difference with the analytical ones.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.620-625
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• 2007

Autofrettage process is used for internal forming and sizing of cylinder designed to withstand high internal pressures. Once the tube is autofrettaged, it needs to be machined to its final dimensions both at the bore and its outer surface. This paper presents an analytical analysis and numerical analysis of machined compound cylinder using finite element code, ANSYS10.0. An analytical model for predicting the level of autofrettage following either inner, outer, or combined machining of the compound cylinder is developed for the autofrettage residual stress field is simulated by an autofrettaged pressure. The autofrettaged pressures are obtained by using trying-error method. As autofrettage percentage is 20 %, the numerical results are found to be in almost agreement with the analytical ones. However, as autofrettage percentage is 60 %, the numerical results have a little difference with the analytical ones.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.268-273
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• 2000

In this report, a new method compounding the electrolytic machining with ball end milling process to increase the machining efficiency was introduced. And the cutting characteristics by electrolytic machining conditions was examined. From the experimental results, it was confirm-ed that effect of cutting force reduction obtained at the condition of transpassive state of electrolytic machining conditions.

• 한국정밀공학회지
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• 제13권9호
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• pp.156-164
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• 1996

Tool interference is one of the most critical problems in machining die cavities and punches. When machining concave or convex regions of cavities with large radius tool in rough cutting, the tool easily overcuts or undercuts the portions of the surface, which result in machining inaccuracy. So the generation of interference-free tool path must be required for more efficient rough cutting. In this paper, we present a method for modeling die cavities which consist of simple surface or analytic compoyund surfaces and present an algorithm for checking and removing the tool interference occurred in machining the die cavities. Using these algorithms, we can represent a die cavity, and check the interfer- ence regions, and then remove these interferences. Especially we focus on the side interference in the sides of analytic elements and base surface boundary.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.291-294
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• 2000

Free-form surfaces arise in shipbuilding, automotive and aerospace industries. Specially compound free-form surfaces so do. Machining complicated products consist of compound surface, it is very important to avold and remove tool interferences. By the way, in compound surfaces the tool interference can occur not only in the tool path direction but also in the other direction. A new tool interference detection and correction using tool interference conditions is suggested to identify and correct the tool interference in compound surfaces.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.1025-1028
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• 2001

In this report, a new method compounding the electrolytic machining with ball end milling process to increase the machining efficiency was introduced. From the experimental result, it was confirmed that effect of cutting force reduction and finer surface roughness can be obtained in a certain condition of ball end milling and electrolytic machining conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.959-962
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• 2000

A new method compounding the electrolytic machining with ball end milling process to improve machined surface toughness was examined. From this study, it was confirmed that much smaller cutting force and finer surface roughness can be obtained in a certain condition of ball end milling and electrolytic machining conditions.

• 한국기계가공학회지
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• 제9권3호
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• pp.69-75
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• 2010

A hollow flanged spindle is generally used for the assembly of the driving shaft in some vehicles. This part has conventionally been manufactured by both hot forging and machining process, in which case a circular billet is hot-forged into a flanged spindle blank and then its central part is machined for hollow. Therefore, the development of a new forming technology without further machining processes has strongly been in demand. In this study, a new compound forging process of the hollow flanged spindle was proposed through the finite element simulation. By the proposed compound forging process, both extruding of the spindle body part and piercing for the hollow inside it can be performed at the same time. Metal flow patterns, forging defects and forging forces were investigated through the finite element simulation results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 춘계학술대회 논문집
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• pp.429-433
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• 1995

Compound solid is maded for specially fixed object. A number of compound soild are devided as a unit germetric solid. The special case of rotation about an arbitrary axis makes according selection modelfor transformation. View plane and View region are estiblished for back face removal. After back-face removal eachedge is checked for point of intersection. The designing of of fset surface id maded and tool-path gernerted on the part surface. In tersection point is checked among the offset surfaces. The paper used an efficient algorithm for generating tool paths to apply a notion view volume. Through machining experiments with a 3-axis machining centre, the adequacy of the analysis was confirmed.

• 한국정밀공학회지
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• 제21권3호
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• pp.83-90
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• 2004

This paper proposes a tool path generation method for machining impellers with 5-axis machining center. The shape of impeller is complex, being composed of pressure surface, suction surface and leading edge, and so on. The compound surface which is made of ruled surface such as pressure surface and suction surface and leading edge such as fillet surface, makes the tool path generation much complicated. To achieve efficient roughing, cutting area is divided into two region and then tool radius of maximum size that do not cause tool intereference is selected for shortening machining time. In finishing, accuracy is improved using side cutting for blade surface and point milling for leading edge.