• Title, Summary, Keyword: cooling time

Search Result 1,492, Processing Time 0.046 seconds

The critical characteristics resulted from the slow cooling time in the HTSC bulk fabrication (초전도벌크제작시 서냉시간에 따른 임계특성)

  • 임성훈;강형곤;최명호;임성우;한병성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.185-188
    • /
    • 1997
  • The influence of slow cooling and annealing time in $O_2$ during melting and growth step in MPMG process on J$_{c}$ was investigated. Through the measurement of J$_{c}$ SEM and XRD, it can be observed that the critical characteristics were related with the slow cooling time and annealing time in 02 for melting and growth step of MPMG process. The distribution of critical current density with slow cooling time was the porabolic form and the value of J. was the highest at the 40 hour slow cooling time. And also, the value of J$_{c}$, along the annealing time in $O_2$ in the case of the slow cooling time 40 hour was inclined to increase with annealing time. Consequently, it can be suggested that proper slow cooling titre and annealing time along slow cooling in MPMG process be important to improve the critical characteristics.stics.

  • PDF

Development of Rapid Cooling System using Peltier Device (펠티에 소자를 이용한 급속 냉각시스템의 개발)

  • Jang, M.K.;Lee, G.H.;Noh, K.C.;Jeong, Y.D.
    • Journal of the Korea Society For Power System Engineering
    • /
    • v.13 no.4
    • /
    • pp.38-42
    • /
    • 2009
  • The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. now then, cooling process spends the most of times in Injection molding cycle time. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to $1^{\circ}C$ and had to need 10 minutes for normal operating.

  • PDF

Development of Rapid Cooling System for Injection Mold (사출금형의 급속냉각시스템 개발)

  • Moon, Young-Bae;Choi, Youn-Sik;Jeong, Yeong-Deug
    • 한국금형공학회:학술대회논문집
    • /
    • /
    • pp.111-114
    • /
    • 2008
  • The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to $1^{\circ}C$ and had to need 10 minutes for normal operating. However, if response time of temperature controller and sensor will be increased, the performance of this system will increase.

  • PDF

Development of Rapid Cooling System for Injection Mold (사출금형의 급속냉각시스템 개발)

  • Moon, Young-Bae;Choi, Youn-Sik;Jeong, Yeong-Deug
    • Journal of the Korea Society of Die & Mold Engineering
    • /
    • v.8 no.1
    • /
    • pp.31-34
    • /
    • 2014
  • The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to $1^{\circ}C$ and had to need 10 minutes for normal operating. However, if response time of temperature controller and sensor will be increased, the performance of this system will increase.

  • PDF

The Critical Characteristics Attributed to the Slow Cooling and Annealing Time in the Melting Growth (용융성장시 서냉시간과 후열처리시간에 따른 임계특성)

  • 임성훈;최명호;강형곤;정동철;박종광;한병성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.4
    • /
    • pp.327-333
    • /
    • 1998
  • The influence of slow cooling and annealing time in $O_2$in MPEG process on $J_c$ was investigated. From the measurement of $J_c$,SEM and XRD, it was observed that the critical current density was related with the slow cooling time and annealing time in $O_2$. The value of $J_c$ was the highest at slow cooling time of 40 hour. And also, the value of $J_c$ along the annealing time in $O_2$in the case of the slow cooling time of 40 hours was inclined to increase with annealing time. Consequently, it can be suggested that proper slow cooling time and annealing time after slow cooling in MPMG process be important to improve the critical characteristics.

  • PDF

Comparison of cooling effects according to cooling methods in injection mold (사출금형의 냉각회로 종류에 따른 냉각효율의 비교)

  • Noh, Keon-Cheol;Jang, Min-Kyu;Je, Deok-Keun;Choi, Yoon-Sik;Jeong, Yeong-Deuk
    • Journal of the Korea Society of Die & Mold Engineering
    • /
    • v.8 no.1
    • /
    • pp.10-13
    • /
    • 2014
  • Plastic products are producted more than 70% of total processes by the injection molding. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The time and system of cooling affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. This study shows comparative study about cooling efficiency of spiral channel and baffle and observed the variation of time to freeze of molding As the result of CAE experiments, cooling rate by spiral channel had faster than baffle and as freeze time was decreased. Results of this study will be used widely to design for cooling system of injection mold.

  • PDF

Comparison of Linear Channel and Baffle for Cooling Rate in Injection Mold (사출성형금형에서 직선채널과 배플의 냉각효율 비교)

  • Moon, Young-Bae;Choi, Youn-Sik;Jeong, Yeong-Deug
    • Journal of the Korea Society of Die & Mold Engineering
    • /
    • v.6 no.1
    • /
    • pp.1-4
    • /
    • 2012
  • Plastic products are producted more than 70% of total processes in the injection molding. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The time and system of cooling affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, it was made a comparative study about cooling of linear channels and baffles and observed the variation of mold temperature on the coolant's temperature. As the result, the linear channel's cooling rate had faster than baffles and as coolant's temperature was increased, difference of cooling time was increased. Result of this study will be used widely to design for cooling system of injection mold.

  • PDF

Temperature Field and Cooling Rate of Laser Cladding with Wire Feeding

  • Kim, Jae-Do;Peng, Yun
    • Journal of Mechanical Science and Technology
    • /
    • v.14 no.8
    • /
    • pp.851-860
    • /
    • 2000
  • Temperature field and cooling rate are important parameters to influence the properties of clad layer and the heat affected zone. In this paper the temperature field and cooling rate of laser cladding are studied by a two-dimensional time-dependent finite element model. Experiment has been carried out by Nd:YAG laser cladding with wire feeding. Research results indicate that at the beginning of cladding, the width and depth of melt pool increase with cladding time. The cooling rate is related to position, cladding time, cladding speed, and preheating temperature. The temperature near melt pool changes rapidly while the temperature far from melt pool changes slowly. With the increase of cladding time, cooling rate decreases. The further the distance from the melt pool, the lower the temperature and the slower the cooling rate. The faster the cladding speed, the faster the cooling rate. The higher the preheating temperature, the slower the cooling rate. The FEM results coincide well with the experiment results.

  • PDF

Conformal Cooling Channel Manufacturing for the Die (Conformal Cooling Channel 의 구조물 제작)

  • Lee C.W.;Suh J.H.;Woo S.S.;Kim D.J.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.1761-1765
    • /
    • 2005
  • The plastic injection molding industry is increasing pressure to reduce the cycle time in order to improve the productivity. The time of a cooling die is a large part of the cycle time. The conformal cooling channels can reduce the cooling time effectively as compared with conventional production die. It is hard to make the die with a conformal cooling channel by the conventional method. This paper introduces the method of a conformal cooling channel manufacturing by the DMT (Direct Metal Tooling) that is a new technology.

  • PDF

Characteristic of Cold-Weather Concrete by the Variation of Compressive Strength (강도 변화에 따른 한중콘크리트 특성연구)

  • 신성우;김인기;안종문
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.154-159
    • /
    • 1995
  • Cold weather concrete presents the many characteristic variation of quality, according to the mixing and cooling point, the cooling time and the quantity of air besides the compressive strength of concrete. Thus, in this study to verify the character of cold-weather concrete we make the concrete specimens at laboratory and cool them at cooling-melting machine and then test the 7days compressive strength of them, with the variation of compressive strength of concrete, cooling point, cooling time, cooling weather and air quantity. At the results, the compressive strength of concrete decrease in the case of early cooling point, long cooling time, low cooling temperature and the low design compressive strength

  • PDF