• Title/Summary/Keyword: RHA

Search Result 684, Processing Time 0.035 seconds

A Study of Design for Hot Tool to Minimize Radius of Heat Affected Zone in Rapid Heat Ablation process (쾌속 열용삭 공정에서 열반경 최소화를 위한 열 공구 설계에 관한 연구)

  • Kim Hyo-Chan;Lee Sang-Ho;Park Seung-Kyo;Yang Dong-Yol
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.23 no.7 s.184
    • /
    • pp.177-186
    • /
    • 2006
  • In order to realize a three-dimensional shape on CAD, the machining process has been widely used because it offers practical advantages such as precision and versatility. However, the traditional machining process needs a large amount of time in cutting a product and the remained material causes trouble such as inconvenience due to cleaning process. Therefore, a new rapid manufacturing process, Rapid Heat Ablation process (RHA) using the hot tool, has been developed. In this paper, the hot tool for RHA process is designed to minimize radius of heat affected zone. TRIZ well-known as creative problem solving method is applied to overcome the contradictive requirements of the hot tool. For the detailed design of the hot tool, numerical model is established with several assumptions. In order to verify the numerical results, surface temperature of the hot tool is measured with K-type thermocouple at the predetermined location. Numerical and experimental results show that the devised hot tool fulfils its requirements. The practicality and effectiveness of the designed hot tool have been verified through experiments.

Sugar Constituents of Jalapin from Sweet Potato Tubers (고구마樹脂중 잘라핀의 糖構成에 관한 硏究)

  • SU RAE LEE;KOO HEUNG CHUNG;HO SIK KIM
    • Journal of the Korean Chemical Society
    • /
    • v.13 no.1
    • /
    • pp.96-101
    • /
    • 1969
  • Jalapin purified from the tubers of the sweet potato (Ipomoea batatas) was deacylated and subjected to structural elucidation. Complete and degraded acid hydrolyses indicated the presence of L-rhamnose, D-fucose and D-glucose in the molar ratio of 1: 1: 1 and in the increasing order of acid-stability. While two moles of periodate were consumed per mole of the product, D-glucose survived in the oxidation. The following structure was, therefore, proposed tentatively for the deacylated jalapin: L-$Rha_f$-(1${\to}$4)-D-$Fuc_p$-(1${\to}$3)-D-$Glu_p$-(1${\to}$11)-jalapinolic acid.

  • PDF

Development of Rapid Heat Ablation process Using Rotary Hot tool (회전 열공구를 이용한 쾌속 열용삭 공정 개발에 관한 연구)

  • Kim H.C.;Park S.H.;Yang D.Y.;Park S.K.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2005.10a
    • /
    • pp.224-230
    • /
    • 2005
  • In order to realize a three-dimensional shape on CAD, the machining process has been widely used because it offers practical advantages such as precision and versatility. However, the traditional machining process needs a large amount of time in cutting a product and the remained material causes trouble such as inconvenience due to cleaning process. This paper introduces a new rapid manufacturing process called Rapid Heat Ablation process (RHA) using the rotary hot tool to overcome limitations of traditional machining process. The rotary hot tool to satisfy requirements of RHA process is designed and produced. In order to examine relationships between kerfwidth and process parameters such as heat input, speed of tool and speed of revolution, experiments were carried out. In addition, relationship between the kerfwidth and the effective heat input was obtained. Based on the experimental results, double-curved shape was ablated to show the validity of proposed process. In the procedure, the rough cut and fine cut were performed according to the conditions of process parameters without tool change process. The practicality and effectiveness of the proposed process have been verified through ablation of three-dimensional shape.

  • PDF