Study on Shrinkage of Injection Molding Biodegradable Materials

2006 ◽  
Vol 505-507 ◽  
pp. 199-204
Author(s):  
Yih Lin Cheng ◽  
Ying Wei Lee
Keyword(s):  
Injection Molding ◽  
Mass Production ◽  
Injection Pressure ◽  
Environmental Concerns ◽  
Biodegradable Materials ◽  
Medical Applications ◽  
Injection Speed ◽  
Major Index ◽  
Production Processes ◽  
Optimal Injection

Due to environmental concerns, biodegradable materials, which are currently used in many medical applications, are being considered as a candidate for replace plastics in the future. One of the most common mass production processes to shape biodegradable materials is injection molding. However, the material manufacturers usually do not provide optimized parameter information. In this research, two biodegradable materials, PLA 3001D and Biomax, are investigated. Experiments are conducted utilizing the Taguchi method to determine optimal injection molding parameters, which include injection speed, injection pressure, holding pressure, and cooling time. Shrinkage was the major index to evaluate the injection results. As a result, the best combinations of parameters were determined.

Effect of Processing Conditions on the Shrinkage and Warpage of Glass Fiber Reinforced PP Using Microcellular Injection Molding

2012 ◽  
Vol 501 ◽  
pp. 294-299 ◽  
Author(s):  
Zhi Bian ◽  
Peng Cheng Xie ◽  
Yu Mei Ding ◽  
Wei Min Yang
Keyword(s):  
Injection Molding ◽  
Glass Fiber ◽  
Injection Pressure ◽  
Mold Temperature ◽  
Process Conditions ◽  
Fiber Reinforced ◽  
Injection Speed ◽  
Glass Fiber Reinforced ◽  
Microcellular Injection Molding ◽  
Molded Parts

This study was aimed at understanding how the process conditions affected the dimensional stability of glass fiber reinforced PP by microcellular injection molding. A design of experiments (DOE) was performed and plane test specimens were produced for the shrinkage and warpage analysis. Injection molding trials were performed by systematically adjusting six process parameters (i.e., Injection speed, Injection pressure, Shot temperature, SCF level, Mold temperature, and Cooling time). By analyzing the statistically significant main and two-factor interaction effects, the results showed that the supercritical fluid (SCF) level and the injection speed affected the shrinkage and warpage of microcellular injection molded parts the most.

Effects of process parameters on the formability of sheet metal during plastic injection forming

2020 ◽  
Vol 62 (5) ◽  
pp. 535-543
Author(s):  
Mirigul Altan ◽  
Bora Sener ◽  
Mirigul Altan
Keyword(s):  
Injection Molding ◽  
Sheet Metal ◽  
Injection Pressure ◽  
Industrial Applications ◽  
Effective Parameter ◽  
Melt Temperature ◽  
Injection Speed ◽  
Aluminum Sheets ◽  
Plastic Injection ◽  
Thinning Rate

Abstract Plastic injection forming (PIF) is an alternative sheet metal forming method for complex geometrical parts with dimensions in low tolerance. This method is a combination of injection molding and hydroforming in which a molten polymer material has been injected over a sheet metal via a plastic injection molding machine. In this study, aluminum sheets 1.5 mm thick were shaped by PIF at various injection pressures, melt temperatures and injection speed. The effects of these parameters on the formability of the sheet metal were investigated using the experimental design technique. The thinning rate, flange radius and the hardness values of the shaped sheets were considered in the experimental study. Injection pressure was found to be the most effective parameter and melt temperature was the second degree effective parameter for the thinning rate. The usability of the PIF process in industrial applications as an alternative method was emphasized by comparing PIF with conventional hydroforming by means of the finite element method (Ls-Dyna). A 2.07 % deviation was observed between the FE results for hydroforming and the experimental results for PIF.

scholarly journals Fabrication of Micro-Structured Polymer by Micro Injection Molding Based on Precise Micro-Ground Mold Core

Micromachines ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 253 ◽  
Author(s):  
Yanjun Lu ◽  
Fumin Chen ◽  
Xiaoyu Wu ◽  
Chaolan Zhou ◽  
Yan Lou ◽  
...  
Keyword(s):  
Injection Molding ◽  
Mass Production ◽  
Injection Pressure ◽  
Machining Accuracy ◽  
Filling Rate ◽  
Micro Structure ◽  
Micro Injection Molding ◽  
Melt Temperature ◽  
Array Structures ◽  
Micro Structures

Precise micro-grinding machining was proposed to fabricate regular and controllable micro-grooved array structures on the surface of mold cores to realize the mass production and manufacturing of micro-structured polymer components by micro injection molding in this paper. First, the 3D topographies and section profiles of micro-ground mold cores and micro-formed polymers with different micro-structure parameters were presented. Then, the surface roughness of mold cores and polymers were compared. Next, the relationships between machining accuracy of mold core ground by micro-grinding and filling rates of micro-structured polymer formed by micro injection molding were investigated. Finally, the influences of micro injection molding parameters on the filling rate of micro-structures polymer were investigated. It is shown that the micro-structured polymer can be effectively and rapidly fabricated using the proposed method. The experimental results indicate the highest form accuracy of the micro-grooved mold core and the filling rate of micro-structured polymer can reach to 4.05 µm and 99.30%, respectively. It is found that the filling rate of the micro-structured polymer roughly increased with increasing machining accuracy of the mold core. The injection pressure had the greatest influence on the filling rate of the injection formed polymer, while the melt temperature had the least influence.

ANALISIS PARAMETER INJECTION MOLDING TERHADAP WAKTU SIKLUS DAN CACAT FLASH PRODUK TUTUP BOTOL 180 ML MENGGUNAKAN METODE TAGUCHI

ROTOR ◽  
2017 ◽  
Vol 10 (1) ◽  
pp. 45
Author(s):  
Andika Wahyu Prasanko ◽  
Dwi Djumhariyanto ◽  
Agus Triono
Keyword(s):  
Injection Molding ◽  
Taguchi Method ◽  
Cycle Time ◽  
Human Life ◽  
Injection Pressure ◽  
Injection Speed ◽  
Beverage Industry ◽  
Food And Beverage Industry ◽  
Food And Beverage ◽  
Nozzle Temperature

At present plastic becomes inseparable from human life especially in the food and beverage industry. One of the methods used in the manufacturing process of plastic products is injection molding. Injection molding is one of manufacturing technique that consists of a series of cyclical processes and is used to produce thermoplastic materials. The effect of the combination of process parameters impact on the product results such as the quantity and quality of the product, the non-conformity of the parameters causes the production to be not optimal. One method that can be used for optimization is the taguchi method. The taguchi method is a set of special matrices called orthoghonal arrays that are used as reference in the determination combination of parameters and level values. The purpose of this research is to determine the optimal cycle time and net of the product on the process of making 180 ml bottle cap but by minimizing flash defects. The method used in this phase is ANOVA, and the calculation of taguchi method by using minitab 16 software. From the result of the research, the result of optimal condition is combination injection pressure 1320 bar, injection speed 50 mm/s, holding pressure 300 bar, and nozzle temperature 255oC produces a cycle time value of 15.72 seconds and netto 3.56 grams. This result is better than the setting of the company that produces 16.66 seconds cycle time and entered in the net range of 4 ± 0.5 grams resulting in an increase in production of 5.97%. While with combination of injection pressure 1280 bar, injection speed 50 mm / s, holding pressure 300 bar, and nozzle temperature 245oC resulted in fewer number of flash defects compared to company setting that is 12 units from 80 units of sample. Keywords: flash deffect, injection molding, taguchi method, cycle time

Reduction in Defect Rate by Taguchi Method in Plastic Injection Molded Components

2012 ◽  
Vol 488-489 ◽  
pp. 269-273 ◽  
Author(s):  
G.S. Dangayach ◽  
Deepak Kumar
Keyword(s):  
Injection Molding ◽  
Injection Pressure ◽  
Processing Parameters ◽  
Process Conditions ◽  
Melt Temperature ◽  
Defect Rate ◽  
Packing Pressure ◽  
Optimal Injection ◽  
Packing Time ◽  
Plastic Injection

In the present era, competition gets tougher; there is more pressure on manufacturing sectors to improve quality and customer satisfaction while decreasing cost and increasing productivity. These can be achieved by using modern quality management systems and process improvement techniques to reduce the process variability and driven waste within manufacturing process using effective application of statistical tools. Taguchi technique is well known technique to solve industrial problems. This technique is fast and can pinpoint the chief causes and variations. Plastic injection molding is suitable for mass production articles since complex geometries can be obtained in a single production step. The difficulty in setting optimal process conditions may cause defects in parts, such as shrinkage and warpage. In this paper, optimal injection molding conditions for minimum shrinkage were determined by the Taguchi design of experiment (DOE) approach. Polypropylene (PP) was injected in circular shaped specimens under various processing parameters: melt temperature, injection pressure, packing pressure and packing time. S/N ratios were utilized for determining the optimal set of parameters. According to the results, 2400 C of melt temperature, 75 MPa of injection pressure, 50 MPa of packing pressure and 15 sec. of packing time gave minimum shrinkage of 0.951% for PP. Statically the most significant parameter was melt temperature for the PP. Injection pressure had the least effect on the shrinkage. The defect rate was reduced from 14% to 3%.

scholarly journals PENGARUH INJECTION TIME DAN BACKPRESSURE TERHADAP CACAT PENYUSUTAN PADA PRODUK KEMASAN TOPLES DENGAN INJECTION MOLDING MENGGUNAKAN MATERIAL POLISTYRENE

2017 ◽  
Vol 4 (3) ◽  
pp. 15
Author(s):  
U. Wahyudi
Keyword(s):  
Quality Control ◽  
Injection Molding ◽  
Injection Pressure ◽  
Cooling Time ◽  
Injection Time ◽  
Injection Speed

Produk kemasan kue atau toples adalah produk rumah tangga yang sangat dibutuhkan untuk menaruh berbagai macam-macam kue kering, Produk plastik ini terdiri dari badan dan tutup, kedua komponen ini pada saat dirakit memerlukan kepresisian yang lumayan bagus oleh karena material yang digunakan plastik, maka faktor penentuan penyusutan(shrinkage) memegang peranan sangat penting pada saat dicetak dengan mesin injection molding yang menggunakan material polistyrene. Pada saat produksi pernah terjadi kegagalan produk fitting terlalu kencang dan ada juga fitting yang kendor antara tutup dengan badan akibatnya produk tidak lolos produksi oleh quality control. Didalam tugas akhir ini penulis melakukan langkah-langkah bagaimana teknik menganalisa cacat penyusutan (shrinkage) material plastik terutama di khususkan material polystyrene dimulai dari proses injection molding lalu diambil sampel produk dengan tingkat pengujian yang berbeda lewat settingan parameter. Dengan waktu injeksi dan backpressure yang berbeda-beda akan menghasilkan ukuran produk dan nilai shrinkage yang berbeda pula. Nilai temperatur leleh yang baik digunakan untuk material polistyrene dengan ketebalan produk kemasan toples 0,75 mm, diameter produk 140,94 mm dan tinggi 58,29 mm. berkisar antara 2400C – 3100C. Cacat penyusutan pada material polystyrene pasti ada walaupun tidak sebesar pada material lain seperti PP dan LDPE dan bisa diminimalkan dengan setting parameter proses yang bagus. Nilai shrinkage yang baik dan ideal dan sesuai standar terjadi pada settingan backpressure 30 kgf/cm² dengan waktu injeksi yaitu 2 detik. Dengan  parameter yang konstan, mulai dari injection speed 120 cm/s, 65 cm/s. Injection pressure 1400 kgf/cm² dan pack pressure 1200 kgf/cm², pack time 0,5 sec, Shot size 55 mm, kemudian cooling time 2 detik dengan temperatur mold 600 C.

Optimization and Design for Parameter in Injection Molding Technology of Cell Shell of Polypropylene

2011 ◽  
Vol 189-193 ◽  
pp. 537-540
Author(s):  
Jia Min Zhang ◽  
Ming Yi Zhu ◽  
Zhao Xun Lian ◽  
Rong Zhu
Keyword(s):  
Injection Molding ◽  
Injection Pressure ◽  
Mold Temperature ◽  
Injection Molding Process ◽  
Technological Parameters ◽  
Molding Process ◽  
Melt Temperature ◽  
Injection Speed ◽  
Technical Parameters ◽  
High Degree

The use of L27 (35) orthogonal to the battery shell injection molding process is optimized. The main factors of technical parameters were determined mould temperature, melt temperature, the speed of injection, injection pressure, cooling time.On the basis of actual production, to determine the factors values of different process parameters.Combination of scrapped products in key (reduction and a high degree of tolerance deflated) tests were selected in the process parameters within the scope of the assessment. Various factors impact on the product of the total height followed by cooling time, mold temperature, melt temperature, injection pressure, injection speed from strong to weak .The best products technological parameters were determined.Good results were obtained for production.

scholarly journals ANALYSIS OF INJECTION MOLDING PROCESS TO REDUCED DEFECTS (SHORT-SHOT)

2020 ◽  
Vol 5 (6) ◽  
pp. 113-119
Author(s):  
L.D.Mahajan ◽  
P.N.Ulhe
Keyword(s):  
Injection Molding ◽  
Process Parameters ◽  
Injection Pressure ◽  
Quality Characteristic ◽  
Injection Molding Process ◽  
Molding Process ◽  
Plastic Specimen ◽  
Optimal Injection ◽  
Short Shot

This paper deals with optimal injection molding process parameters for minimum short shot. In this study, analyses of injection molding process parameters were carried out to reduced defects and minimize short shots. Optimal injection molding conditions for minimum short shot were determined by the DOE technique of Taguchi and the analysis of variance (ANOVA) methods. For this study CPVC plastic specimen was tested. Determination of the optimal Injection molding process parameters were based on S/N ratios. According to results mold closing speed had significant effect on quality characteristic. Mold pressure and Injection pressure had no significant effect

scholarly journals Optimization on the Injection Molding Propypopylene Parameters Using Central Composite Design for Minimizing Defects

2020 ◽  
Vol 55 (2) ◽  
Author(s):  
Moh. Hartono ◽  
Pratikto ◽  
Purnomo B. Santoso ◽  
Sugiono
Keyword(s):  
Injection Molding ◽  
Central Composite Design ◽  
Injection Pressure ◽  
Holding Time ◽  
Clamping Force ◽  
Molding Process ◽  
Injection Speed ◽  
Injection Temperature ◽  
Central Composite ◽  
Plastic Products

This study aims to simultaneously forecast and investigate the optimization process characterization of the design of controlled parameters in the injection process of polypropylene molding including injection pressure combination, clamping force, injection temperature, injection speed, and holding time, and their interaction to produce qualified plastic by minimizing defects. The experimental methods used the central composite design of response surface method with five factors and a variety of levels. This method is more effective because it is an improvement on and a development from previous studies—especially those related to the plastic molding process. Additionally, it can simultaneously predict and optimize the obtaining of the highest quality plastic products as well as minimizing defects. The results are in the form of a combination of control level factors and interactions among the factors that generate the robust output of plastic products with minimum defects. Moreover, the optimum settings of the parameters provides a global solution at an injection temperature of 275°C, injection pressure of 75 bar, injection speed of 98%, clamping force of 88 tons, and a holding time of 8 seconds to generate a response to product probability defects by 0.0062. The benefit is that it can reveal the behavior and characteristics of parameter design and their interactions in the plastic injection molding process to produce qualified plastics and minimize product defects.

scholarly journals In-mold and Machine Sensing and Feature Extraction for Optimized IC-tray Manufacturing

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1348 ◽  
Author(s):  
Shih-Chih Nian ◽  
Yung-Chih Fang ◽  
Ming-Shyan Huang
Keyword(s):  
Injection Molding ◽  
Optimal Parameter ◽  
Flow Behavior ◽  
Injection Pressure ◽  
Effective Control ◽  
Injection Molding Process ◽  
Molding Process ◽  
Operator Experience ◽  
Injection Speed ◽  
Screw Position

Injection molding is a mature technology that has been used for decades; factors including processed raw materials, molds and machines, and the processing parameters can cause significant changes in product quality. Traditionally, researchers have attempted to improve injection molding quality by controlling screw position, injection and packing pressures, and mold and barrel temperatures. However, even when high precision control is applied, the geometry of the molded part tends to vary between different shots. Therefore, further research is needed to properly understand the factors affecting the melt in each cycle so that more effective control strategies can be implemented. In the past, injection molding was a “black box”, so when based on statistical experimental methods, computer-aided simulations or operator experience, the setting of ideal process parameters was often time consuming and limited. Using advanced sensing technology, the understanding of the injection molding process is transformed into a “grey box” that reveals the physical information about the flow behavior of the molten resin in the cavity. Using the process parameter setting data provided by the machine, this study developed a scientific method for optimal parameter adjustment, analyzing and interpreting the injection speed, injection pressure, cavity pressure, and the profile of the injection screw position. In addition, the main parameters for each phase are determined separately, including injection speed/pressure during the mold filling phase, velocity-to-pressure switching point, packing pressure and time. In this study, the IC tray was taken as an example. The experimental results show that the method can effectively reduce the warpage of the IC-tray from 0.67 mm to 0.20 mm. In addition, the parameters profiles obtained by parameter optimization can be applied for continuous mass production and process monitoring.

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