• Title, Summary, Keyword: Injection Speed

Search Result 790, Processing Time 0.053 seconds

Analysis of the Physical Quantity Variation in the Cavity and the Quality of the Molded Product According to the Injection Speed in Injection Molding

  • Kwon, Soon Yong;Cho, Jung Hwan;Roh, Hyung Jin;Cho, Sung Hwan;Lee, Yoo Jin;Lyu, Min-Young
    • Elastomers and Composites
    • /
    • v.52 no.4
    • /
    • pp.317-325
    • /
    • 2017
  • Molding conditions can be described as factors that determine the quality of a product obtained from injection molding. Many studies have been performed on the injection molding pressure, injection temperature, packing pressure and other molding conditions related to part quality. However, the most accessible factor among the adjustable molding conditions during actual injection is the injection speed. In this study, we simulated the variation of the physical quantity according to injection speed and performed experiments to understand the effect of injection speed on the actual product. A CAE analysis program (Moldflow) was used to simulate and analyze the results using PC and PBT for two models. In order to compare these results with the experimental results, an actual injection molding was performed for each injection speed, and the correlation between simulation and injection molding, especially for the shrinkage of the molded article, was discussed.

A study on the Molding Stability of Hydro-mechanical High Speed Injection Molding for Thin-Walled(0.3mm) LGP (초박형(0.3t) 도광판 적용을 위한 유압식 고속사출성형의 성형 안정성 연구)

  • Kim, J.S.;Oh, J.G.;Jeong, C.;An, H.J.;Hwang, C.J.;Kim, J.D.;Yoon, K.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.422-425
    • /
    • 2008
  • Recently, electronic products and related parts are required to have thin thickness because of small form factor. To go with the trend, LGP(light guide plate) of LCD BLU(Liquid Crystal Display Back light unit: It is one of kernel parts of LCD) for cell phone has the thickness of 0.3 mm and the battery case of cell phone has 0.25 mm. Accordingly, high speed injection molding is required to make products which have thin thickness. High speed injection molding means that the resin is injected into the cavity at higher than normal speed avoiding short shot. In the case of hydro-mechanical high speed injection machine, it requires the design for hydraulic unit to make high injection speed and the design for control unit to control hydraulic unit. In the present paper, we concentrated on the molding stability of hydro-mechanical high speed injection machine to make an LGP of 0.3 mm thickness.

  • PDF

Atomization Characteristics of the High Speed Rotating Injection System with Single Column Orifice (단열식 오리피스를 적용한 고속회전 분무노즐의 미립화 특성)

  • Jang, Seong-Ho;Choi, Seong-Man
    • Journal of ILASS-Korea
    • /
    • v.14 no.3
    • /
    • pp.97-102
    • /
    • 2009
  • The spray characteristics of the high speed rotating fuel injection system were studied. The five variants of rotating fuel nozzle were used by spray test. The diameter of single column injection orifices are varied from 1 mm, 2 mm, 3 mm, 4 mm and 5 mm. We constructed high speed rotating test rig and measured droplet size by PDPA (Phase Doppler Particle Analyzer) system. Also spray was visualized by using high speed camera. In the test results, we could understand that length of liquid column from the injection orifice is mainly controlled by the rotational speeds. SMD is decreased with increasing injection orifice diameter and rotational speeds. Furthermore, from the comparison to the theoritical calculation, we confirmed that SMD is influenced by the liquid film thickness which is formed inner surface of injection orifice.

  • PDF

An Experimental Study on the Improvement of Turbocharger Lag by Means of Air Injection in a Turbocharged Diesel Engine

  • Choi, Nag-Jung;Oh, Seong-Mo
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.34 no.7
    • /
    • pp.951-962
    • /
    • 2010
  • An experimental study was performed to investigate the improvement of response performance of a turbocharged diesel engine under the operating conditions of low speed and fast acceleration. In this study, the experiment for improving the low speed and acceleration performance is performed by means of injecting air into the intake manifold of compressor exit during the period of low speed and application of a fast acceleration from low speed. The effects of air injection into the intake manifold on the response performance were investigated at various applicant parameters such as air injection pressure, accelerating rate, accelerating time, engine speed and load. The experimental results show that air injection into the intake manifold at compressor exit is closely related to the improvement of turbocharger lag under low speed and accelerating conditions of a turbocharged diesel engine. During the rapid acceleration period, the air injection into the intake manifold of turbocharged diesel engine indicates the improvement of the combustion characteristics and gas pressure in the cylinder. At low speed range of the engine, the effect of air injection shows the improvement of the pressure distribution of turbocharger and combustion pressure during the period of gas exchange pressure.

Characteristic of the Spray Behavior in accordance with Revolution Speed of Fuel Injection Cam for DI Diesel Engines (직분식 디젤기관의 연료캠 회전속도에 의한 분무 거동 특성)

  • Kim, Y.S.;Ra, J.H.;Lim, B.H.;Ahn, S.K.
    • Journal of the Korea Society For Power System Engineering
    • /
    • v.5 no.3
    • /
    • pp.17-24
    • /
    • 2001
  • In order to investigate a characteristic of the behavior of spray pattern in accordance with running conditions for a DI diesel engine, the PLN Injection system with changeable revolution speed of fuel injection cam was set up, and through this, history curves of injection pressure for a similar real DI diesel engine were able to be displayed. Authors visualized and analyzed the sprays at various revolution speed of fuel injection cam, and found out that fuel distributions of the sprays in the low speed condition were bad, fuel with air was injected from the hole of nozzle at the beginning of injection, and wide spray angle at the early stage of injection became narrower with elapsed time, but wider again at the end of injection.

  • PDF

Control of Processing Conditions for Improvement of vibration Characteristics of Injection Molded Disk (사출성형 디스크의 진동특성 향상을 위한 공정조건 제어)

  • Sin Hyo-Chol;Nam Ji-Geun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.6
    • /
    • pp.615-621
    • /
    • 2006
  • Increased application of optical disks requires more improved dynamic stability of rotating disks. In this study, a new concept of controlling the processing conditions of injection molded disks was developed to improve vibration characteristics. The critical speed, which shows stiffness and dynamic stability of disk, is affected by the residual stress distribution; this varies as functions of distance from the gate and processing condition. The critical speed of disk was calculated with the initial stress taken into consideration, which was determined from injection molding simulation. Choosing melt temperature, mold temperature, filling speed and packing pressure as design parameters, critical speed is maximized with the method of response surface. It is shown that the stability of injection molded disk has been improved for the new condition obtained as a result of the study proposed.

The Effects of Air Injection in Compressor Exit on the Response Performance of a Turbocharged Diesel Engine under the Operating Conditions of Rapid Acceleration. (터보과급디젤기관의 급가속 운전시 압축기출구에의 공기분사가 응답성능에 미치는 영향)

  • 박상규;최낙정
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.24 no.6
    • /
    • pp.110-119
    • /
    • 2000
  • In this paper, an experimental study is carried out under the operating conditions of low speed and rapid acceleration in order to investigate and improve the response characteristics of a turbocharged diesel engine with radial turbine driven by exhaust gas. A rapid acceleration for investigating the response performance is applied to the fuel-pump rack of the engine from 0-10% to 0-40% in steps of 10%, and accelerating time of 1, 2 and 3 seconds is applied to the engine. Further experiment for improving the low speed torque and acceleration performance is also performed by means of injecting air into the inlet manifold at compressor exit during the period of low speed and application of a rapid acceleration. The effects of air injection on the response performance are represented at subjected engine speed with the changes of response performance factors such as air injection pressure, air injection period, accelerating rate, accelerating time and load. From the experimental results obtained throughout this study, it is shown that air injection into the inlet manifold at compressor exit is closely related to the improvement of low speed and acceleration performance of a turbocharged diesel engine.

  • PDF

Molding Stability of Hydro-Mechanical High Speed Injection Molding for Thin-Wall(0.3mm) LGP (박판(0.3mm) 도광판 성형을 위한 유압식 고속사출성형의 성형 안정성 연구)

  • Hwang, C.J.;Kim, J.S.;Oh, J.G.;Jeong, C.;An, H.J.;Heo, Y.M.;Kim, J.D.;Yoon, K.H.
    • Transactions of Materials Processing
    • /
    • v.17 no.8
    • /
    • pp.657-661
    • /
    • 2008
  • Recently, products of electronic industry and related parts are required to have the thickness thinner and thinner to reduce the part weight. To go with this trend, LGP(light guide plate) of LCD-BLU(Liquid Crystal Display-Back Light Unit: It is one of kernel parts of LCD) for cell phone has the thickness of ${\sim}0.3mm$ and the battery case of cell phone has ${\sim}0.25mm$. Accordingly, high speed injection molding is required to mold products which have thinner parts. To achieve high speed injection and proper control of hydraulic unit, various design was applied to conventional injection unit. In the present paper, we concentrated on the molding stability of hydro-mechanical high speed injection machine to make an LGP of 0.3mm thickness.

Retardation Analysis of Plastic Optic Lens according to Injection Speed Variation (사출속도 변화에 따른 플라스틱 광학렌즈의 위상차 해석)

  • Park, Soo-Hyun;Kim, Tae-Kyu;Kwak, Tae-Soo
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.14 no.2
    • /
    • pp.93-98
    • /
    • 2015
  • This study focuses on simulation technology in the injection molding process for plastic optic lenses. The CAE program 3D TIMON was used to predict retardation, flow patterns and warpage deformation. The results were compared to the results of optic lenses as measured using the WPA-100 retardation measurement device with injection molding CAE for retardation predictions. According to the analysis and measured results, the distributions of retardation between the CAE results and the measurement results were similar. It was also confirmed that varying the injection speed had an effect on the injection pressure, warpage deformation and retardation distribution. As the injection speed increases, the injection pressure also increases and warpage deformation decreases. However, as the injection speed increases, the retardation distribution deteriorates.

A Study of Performance Test of High Speed Solenoid for Fuel Injector in Diesel Engine (디젤기관의 분사밸브를 위한 고속 솔레노이드의 성능에 관한 연구)

  • Cho, K.H.;Rha, J.H.;Ahn, S.K.
    • Journal of the Korea Society For Power System Engineering
    • /
    • v.5 no.3
    • /
    • pp.11-16
    • /
    • 2001
  • In the DI diesel engine of passenger cars, common rail injection system have been used to improve the engine performance and reduce the exhaust emission by controlling injection timing, injection pattern, and injection duration. In case that common rail injection system is applied to high speed DI diesel engine, it is necessary to have high response and good repetition characteristics. These characteristics of injector depend on the characteristics of solenoid. Thus, to apply the common rail injection system in the high speed diesel engine, we had designed and made a multi-pole solenoid, and carried out repetition, response test to compare the multi-pole solenoid with the gasoline Injector solenoid. The result shows that repetition and response characteristics of multi-pole solenoid have better characteristics than the gasoline injector solenoid.

  • PDF