• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.20 no.12
• /
• pp.129-135
• /
• 2021

Injection molding is a manufacturing method of melting the polymer resin and injecting it into a mold to molding it into the desired form. Due to the short molding time and outstanding formability, complex products can be shaped with high precision and it is the most widely used polymer molding method. However, there may be areas that are not filled depending on the location of the injection gate where polymer resin is injected. Formability is determined by deformation and surface precision due to the impact of residual stress after molding. Hence, choosing the location of the injection gate is very important and molding analysis of injection molding is essential to reduce the cost of the mold. This study evaluated the injection formability based on the location of the injection gate of the vertical machining center ATC tool port using injection molding analysis and the results were compared and analyzed. Injection molding analysis was conducted on filling, packing, and deformation according to the location of the gate of the ATC tool port. From each injection gate location, filling time, pressure, and maximum deformation were compared. At gate 2, conditions of molding time and the location of the gate were far superior in production and quality. Gate 2 produced the smallest deformation of 0.779mm with the best quality.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.7
• /
• pp.4411-4417
• /
• 2015

The proper design of the gate location for injection molding of plastic goods is obtained from three-dimensional injection molding analysis for various design alternatives. This paper is study on effect of gate location in injection molding. It have a decisive impact on productivity and quality of plastic goods. This objectives of this paper is to analysis effect of hot runner gate location for resin filling, weld line, injection pressure to manufacture of automobile air cleaner upper case with injection molding machine. Thus, to analysis these problems in this paper, location of gate are gave variety in 4 CASEs. In this paper, the CAE simulation considering each variations in location of gate is performed to predict the cause of faulty which appears in the injection molding process.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.4
• /
• pp.795-802
• /
• 1992

A numerical analysis is performed on the turbulent flow in the plain seal with injection. The parameters used in this study are as follows : Reynolds number, rotation speed, injection speed, clearance ratio, injection angle, and axial injection location. Flow pattern and leakage performance due to the variation of parameters are investigated. SIMPLER algorithm is used to solve the Navier-Stokes equation governing steady, incompressible turbulent flow and standard K- .epsilon. turbulent model is used to consider the turbulence effects. The leakage performance is significantly enhanced with injection. The increases of the injection flow rate and be rotation speed of the shaft cause the leakage performance to the increased. With the increase of the Reynolds number the leakage performance is diminished. At the injection angle of 90deg, the leakage coefficient has a minimum value. The pressure drop has a maximum value at axial center location but the injection location has little effect on the pressure drop. Clearance ratio has a significant effect on the pressure drop.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.445-446
• /
• 2007

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.10
• /
• pp.5968-5973
• /
• 2014

The gate location in injection molding has a significant influence on the quality and productivity. Therefore, injection molding CAE is used to determine the gate location. With increasing injection molding CAE and the adoption of a 3D mesh, which takes more computation time for analysis, gate location optimization in the shortest time and least resources is the most challenging issue. In this paper, we propose a methodology for optimization based on the flow length to consider the flow balance and weld line. In addition, the flow balance is obtained in the disc-type plate while the weld lines exit the slit-holes to avoid a stress concentration.

• Journal of Advanced Marine Engineering and Technology
• /
• v.26 no.4
• /
• pp.472-484
• /
• 2002

To analyze the characteristics of air flow and $CO_2$ extinguishant transfer when extinguishant is injected into a closed space similar to marine engine room, a numerical simulation on a space was performed. Flow fields and $CO_2$ concentration fields are calculated according with the variation of the location & injection angle of nozzles. The results of simulation showed that the pattern of recirculation flow was affected greatly with the location & injection angle of nozzles and such a recirculation flow accelerated mass transfer of $CO_2$ and greatly affected the diffusion process of $CO_2$ extinguishant. It is considered that this result of this study can be useful to designing the arrangement of nozzles for the $CO_2$ fire fighting equipments in a marine engine room.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.12 no.1
• /
• pp.5-10
• /
• 2001

Glottal incompetence is one of the causative condition of hoarseness. There have been various methods to improve the glottal conditions. Vocal fold augmentation by injection under direct visual control is a quick and simple operation. Various vocal fold augmentation procedures have developed in recent years. Phonosurgical vocal fold injection can be classified as superficial or deep, by the location of the injection. The choice of material fir vocal fold injection is critical and should be determined by the injection location, technique, and the pathologic condition. There are multiple approaches or methods for vocal f31d injection ; the most widely used are presented in detail in this article.

• Clinical Pain
• /
• v.20 no.2
• /
• pp.59-69
• /
• 2021

Patients with pain, numbness, and weakness in their elbows, wrists, and hands often need proper rehabilitation treatments. Among them, musculoskeletal injection therapy should be performed after a full evaluation of the patient, taking into account history and physical examination leading to clinical diagnosis. General rules such as accurate diagnosis and injection materials selection are used to achieve maximum benefit with minimal side effects. During injection, patient location, aseptic care, penetration techniques, follow-up and follow-up care must be maintained. Specific techniques may vary depending on the type, lesion, and location of the injection therapy. For optimal effectiveness, physician should inject directly into the lesion and avoid the injection of surroundings as much as possible. Therefore, ultrasound-guided injections are needed to accurately inject. These conditions and other conditions of the hands, wrists, and elbows can be effectively diagnosed and treated with diagnostic ultrasound and ultrasound-guided injections.

• Transactions of Materials Processing
• /
• v.12 no.2
• /
• pp.134-140
• /
• 2003

Polymers such as polypropylene or polyethylene offer a unique feature of producing an integral hinge, which can flex over a million times without causing a failure. With such advantage manufacturing, time and cost required at the assembly stage can be eliminated by injecting the whole part as one piece. However, due to increased fluidity resistance at hinges during molding, several defects such as short shot or premature hinge failure can occur with the improper selection of gate locations. Therefore, it is necessary to optimize flow balancer in injection molding of part with hinges before actually producing molds. In this paper, resin flow patterns depending on several gate positions were investigated by numerical analyses of a simple strip part with a hinge. As a result, we found that the properly determined gate location leads to better resin flow and shorter hesitation time. Finally, injection molding tryouts using a mold that was designed one of the proposed gate systems were conducted using polypropylene that contained 20% talc. The experiment showed that hinges without defects could be produced by using the designed gate location.

• Journal of Soil and Groundwater Environment
• /
• v.22 no.3
• /
• pp.42-49
• /
• 2017

TOUGH2 was used to simulate the migration of $CO_2$ injected into a sandy aquifer. A series of numerical simulations was performed to investigate the effects of a low-permeability layer (LPL) embedded in the aquifer on the injection rate and the pressure distribution of $CO_2$. The results show that the size and location of the LPL greatly affected the spread of $CO_2$. The pressure difference between two points in the aquifer, one each below and above the LPL, increased as the size of the LPL increased, showing a critical value at 200 m, above which the size effect was diminished. The location of the LPL with respect to the injection well also affected the migration of $CO_2$. When the injection well was at the center of the LPL, the injection rate of $CO_2$ decreased by 5.0% compared to the case with no LPL. However, when the injection well was at the edge of the LPL, the injection rate was decreased by only 1.6%. The vertical distance between the injection point and the LPL also affected the injection rate. The closer the LPL was to the injection point, the lower the injection rate was, by up to 8.3%. Conclusively, in planning geologic storage of $CO_2$, the optimal location of the injection well should be determined considering the distribution of the LPL in the aquifer.