• Title/Summary/Keyword: 회전성형

Search Result 187, Processing Time 0.028 seconds

Effect of Barrel Temperature and Screw Speed on Characteristics of Extruded Raw Ginseng (배럴온도와 스크루 회전속도에 따른 압출성형 수삼의 특성)

  • Ha, Dae-Cherl;Lee, Jong-Won;Kim, Na-Mi;Ryu, Gi-Hyung
    • Journal of Ginseng Research
    • /
    • v.29 no.2
    • /
    • pp.107-112
    • /
    • 2005
  • The objective of this study was to determine effects of the die temperature(100 and $120^{\circ}C$) and screw speed(200 and 300 rpm) on the characteristics of extruded raw ginseng such as crude saponin, ginsenosides, maltol and the color of powder. Crude saponin content increased after extrusion-cooking. Ginsenoside $Rg_1\;and\;Rg_2$ that contained in red ginseng increased from 0.2275 mg/g to 0.2835 mg/g$(Rg_l)$ and 0.1164 mg/g to 0.2230 mg/g$(Rg_2)$ with the increase in die temperature from 100 to $120^{\circ}C$, which increased with the decrease in screw speed from 300 to 200 rpm. Maltol, specific component in red ginseng was detected in extruded ginseng. Total sugar content was not changed by extrusion process, however reducing sugar decreased with the increase in die temperature from 100 to $120^{\circ}C$. In conclusion extrusion process can be applied to red ginseng manufacturing by controling extrusion process variables such as extrusion temperature and screw speed.

Development of Rotational Molds for Continuous Casting of Rotor (Rotor 연속주조를 위한 회전형 주형개발)

  • Lee, Yang-Chang;Bae, Byeong-Gyu;Chang, Hyun-Seok;Lee, Joon-Seong;Choi, Yoon-Jong;Kwon, Dong-Cheol;Song, Byeong-Mok
    • Proceedings of the KAIS Fall Conference
    • /
    • 2011.05b
    • /
    • pp.840-843
    • /
    • 2011
  • 본 논문은 모터의 회전자를 연속적으로 주조하기 위한 주형 개발을 위해 주조 유동해석를 통해 그 결과를 반영하였다. 주형을 제작하고, 성형한 결과로 수평형은 슬리브가 수평구조이고, 고속으로 작동하면서 공기와 기타 가스빼기가 원활하지 않음에 제품 성형률이 매우 떨어짐을 알 수 있었다. 현재 이를 해결하기 작업자들의 경험에 많이 의지하고 있다. 수직형은 슬리브 구조가 수직으로 되어있어 슬리브가 고속으로 작동할 때, 수평형과 달리 용액이 층류형태로 유지되면서 공기나 기타 가스발생이 매우 적어 안정된 주물제품이 성형됨을 알 수 있었다.

  • PDF

A Study on the Uniform Thickness Distribution in Superplastic Blow Forming Process (초소성 블로우 성형품의 두께분포 균일화 연구)

  • Lee, Jeong-Hwan;Kim, Hyeon-Cheol;Lee, Yeong-Seon;Lee, Sang-Yong;Sin, Pyeong-U
    • Transactions of Materials Processing
    • /
    • v.7 no.6
    • /
    • pp.610-619
    • /
    • 1998
  • The superplastic blow forming technology has advantages of cost reduction and low material consumption. compared to the conventional sheet metal forming technology due to the capability of precisely forming with high elongation and low flow stress. however it has a disadvantage that its partial thickness distribution is non-uniform. A processing technology like diaphragm forming has been developed even though it is difficult to prepare materials for superplastic blow forming. in this study a hemisphere forming of sheet before superplastic forming. It was found that the rotary forming material was less in quantity of cavitation at pole than that of hemisphere part that was superplastic formed without rotary forming treatment. Also discussed are the critical strain which is closely related to cavity shape and size.

  • PDF

Etiology and Treatment of Revision Shoulder Arthroplasty (견관절 인공관절 재치환술의 원인과 치료)

  • Kim, Young-Kyu;Jung, Kyu-Hak
    • Journal of the Korean Orthopaedic Association
    • /
    • v.54 no.2
    • /
    • pp.100-109
    • /
    • 2019
  • The rapidly increasing rate of shoulder arthroplasty is certain to increase the number of revision arthroplasties because of parallel increases in complication numbers. It has been widely reported that the causes of revision shoulder arthroplasty include rotator cuff deficiency, instability, glenoid or humeral component loosening, implant failure, periprosthetic fracture, and infection. Revision arthroplasty can be technically challenging, and surgical options available for failed shoulder arthroplasty are limited, especially in patients with glenoid bone loss or an irreparable rotator cuff tear. Furthermore, the outcomes of revision arthroplasty are consistently inferior to those of primary arthroplasty. Accordingly, surgical decision making requires a good understanding of the etiology of failure. Here, we provide a review of indications of revision arthroplasty and of the surgical techniques used by failure etiology.

Treatment of Painful Rotator Interval Widening After Subcoracoid Decompression in Elite Archer - Case Report - (양궁 선수의 오구 충돌 증후군의 치료 후 발생한 회전근 간격의 손상에 대한 치료 - 증례 보고 -)

  • Park, Jin-Young;Lee, Seung-Jun
    • Clinics in Shoulder and Elbow
    • /
    • v.13 no.2
    • /
    • pp.280-285
    • /
    • 2010
  • Purpose: Coracoid impingement syndrome refers to subscapularis impingement between the coracoid process and lesser tuberosity of the humerus, and pain may occur when the arm is positioned in forward flexion, internal rotation and adduction. This position is common for archers. Material and methods: A female archer with coracoid impingement syndrome that was uncontrolled by conservative therapy underwent arthroscopic subcoracoid decompression. At the 20th postoperative month of follow up, she complained of painful rotator interval widening and so she underwent arthroscopic rotator interval plication. Results: At the postoperative 6th month of follow up after the second operation, she showed no pain and good functional results, and she returned to competing as an archer. Conclusion: We have reported here on a case of successful treatment of painful rotator widening after subcoracoid decompression in an elite archer.

Properties of Extracts from Extruded Root and White Ginseng at Different Conditions (압출성형 공정변수에 따른 건조수삼과 백삼 압출성형물의 침출속도 및 침출물 특성)

  • Kim, Bong-Soo;Ryu, Gi-Hyung
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.34 no.2
    • /
    • pp.306-310
    • /
    • 2005
  • The comparison in release rate constant and properties of extracts from extruded raw ginseng and extruded white ginseng was conducted to apply extrusion process for manufacturing of released ginseng tea bag. Dry raw ginseng and white ginseng powder were extruded at 20∼30% moisture content and 200∼300 rpm by using an experimental twin-screw extruder. Browness and redness (both indicated the releasing of saponin and ginsenosides) were increased with the increase in the screw speed and the decrease of moisture content. Crude saponin and water solubility index (WSI) of both ginseng also share the same behaviour against the level of screw speed and moisture content, as well as browness and redness. The particle size effects of extruded raw ginseng at 20% and 28% moisture content on absorbance of released extract at 260 up to 560 nm, WSI, and water absorption index were determined. While particle size decreased from 800∼1000 nm to 200∼500 nm, absorbance and WSI are decreased. Absorbance and WSI shown increasing level while moisture content was decreased. In conclusion, the formation of pores by expansion and disruption of cell wall in extrusion cooking were obviously responsible to increase the amount of released extract of extruded ginseng and its WSI as well. The extrusion process turns out be the efficient process for manufacturing of commercial ginseng tea product than those of other thermal processes.

A Study on Quality Assurance for Rotational Molding Products (회전성형 제품의 품질 개선을 위한 연구)

  • Lee, Jung-Ki;Han, Hui-Duck;Kim, Hyun-Joo
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.28 no.6
    • /
    • pp.826-837
    • /
    • 2004
  • Rotational molding is a plastics processing technique that is ideally suited to producing relatively large, hollow, seamless parts which are partially or totally enclosed. Designers of plastic parts turn to rotational molding to produce small or large parts of unusual shape that cannot be produced as one piece by other processes, e.g., blow molding and thermoforming. In this paper, in order to enhance the quality of rotational molding plastic products, 1) surface features for the plastic products are characterized by using an image analysis system, 2) maximum tensile strength for the plastic products that are made of materials that consist of Samsung-Atofina R90lU, pigments and two different kinds of calcium carbonate (OMYA CaCO$_3$) is measured and compared with each other by using an Instron universal testing machine, 3) thickness for the plastic products is non-destructively measured to investigate the quality of the plastic products by using an A-scan ultrasonic tester.