Injection Speed (injection + speed)

Distribution by Scientific Domains


Selected Abstracts


Systematic optimization for the evaluation of the microinjection molding parameters of light guide plate with TOPSIS-based Taguchi method

ADVANCES IN POLYMER TECHNOLOGY, Issue 1 2010
Te-Li Su
Abstract A back light module is a key product for providing sufficient light source for a liquid crystal display (LCD). The light guide plate (LGP), used to increase the light usage rate, is a key component in the back light module. This study researches the microinjection molding process parameters and the quality performance of the LGP. Its purpose was to develop a combining Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) with the Taguchi method. This is to optimize the multiquality performance of the LGP for the injection molding manufacturing process, in which both the LCD and the LGP spontaneously produce the best quality performance for V-cut depth and angle. First, an L18 orthogonal array was planned for the manufacturing parameters that affect the microinjection molding process. These included cooling time, mold temperature, melt temperature, injection speed, injection pressure, packing pressure, packing switching, and packing time. The TOPSIS was used to deal with the single-quality optimization disadvantage of the Taguchi method. Then, the TOPSIS response table was used to obtain the optimized manufacturing parameters combination for a multiresponse process optimization. From the analysis of variance, the significant factors for the quality performance of the LGP could be obtained. In other words, by controlling these factors, it was possible to efficiently control the quality performance of the LGP. Finally, with the five verified experiments, the optimized processing parameters came within a 95% confidence interval. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:54,63, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20181 [source]


Incidence of fentanyl-induced cough and injection speed

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009
K.-C. Hung
No abstract is available for this article. [source]


Effects of conductive fibers and processing conditions on the electromagnetic shielding effectiveness of injection molded composites

POLYMER COMPOSITES, Issue 6 2002
S. Y. Yang
This paper investigates the electromagnetic interference shielding effectiveness (EMI SE) of injection molded ABS disks filled with stainless steel fibers (SSF) and nickel-coated graphite fibers (NGF). The effects of fiber type, fiber length and weight percentage on SE were studied. Optical microscope (OM) and scanning electron microscopy (SEM) observations of the fiber distribution and dispersion were used to aid interpretation of the deviation on SE. The effects of processing conditions such as ring gate angles and injection speed on SE and fiber dispersions were also investigated. It is found that the SE of SSF filled disks is better than that of NGF with the same fiber length and weight percentage. The SEM shows that the SSF with severe twists connect with each other to form a three-dimensional network. Nevertheless, the NGF break into straight fragments, which make it difficult to form networks. With the same type of fiber (SSF), the critical concentration of 6mm was similar to that of 4mm. But the SE of 6mm is a little higher than that of 4mm. Minor improvements of SE values were obtained with expanded ring gate angles. Gate design and injection speed both change filling patterns. [source]


A robust shock and noise model for the manufacturing of molded LDPE foams

POLYMER ENGINEERING & SCIENCE, Issue 12 2008
S. Chedly
The article concerns the injection manufacturing process of molded foam sheets and their intrinsic shock and noise performances. The main goal is to optimize the physical performances of molded plastic foams at an early stage in their design and manufacturing. The effects of injection process parameters on the properties of molded LDPE foams are investigated. The input optimization parameters considered are: injection temperature, mold temperature, injection speed, plasticization back pressure, and screw rotation speed during the plasticization phase. The output optimization parameters considered are: density, shock absorption, and acoustic absorption. The experimental design method made use of the Taguchi table and central composition design. This allows us to identify simplified mathematical models for input/output and to detect the most influential input in the injection process. We conclude by validating the models and their robustness. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers [source]


Effects of molding conditions on transcription molding of microscale prism patterns using ultra-high-speed injection molding

POLYMER ENGINEERING & SCIENCE, Issue 9 2006
H. Yokoi
In this study, we performed a series of molding tests to investigate the potential of microscale transcription of polymer by ultra-high-speed injection molding (UHSIM). During the tests, the injection speed was varied up to a maximum of 995 mm/s. Polymethyl methacrylate was molded under various injection molding conditions, including cavity vacuum pumping process, so as to replicate an electroformed nickel stamper exhibiting V-grooves with a pitch of 50 ,m. Surface configurations of molded samples were observed and measured using a laser scanning microscope. The transcription ratio (TR) is defined as the ratio of the depths of V-grooves in both the molded samples and the stamper. An excellent average TR of 0.97 was performed when molding at an injection rate of 800 cm3/s (injection speed of 995 mm/s), mold temperature of 80°C, and holding pressure of 120 MPa. In addition, the effect of vacuum on transcription molding was investigated in detail; the result proved that vacuum is an important factor in the enhancement of transcription fidelity. The strong influence of injection rate on the TR indicates the applicability of UHSIM to the field of transcription molding of polymers. POLYM. ENG. SCI. 46:1140,1146, 2006. © 2006 Society of Plastics Engineers. [source]