Experimental and Numerical Analysis of Liquid-Forming

2015 ◽  
Vol 651-653 ◽  
pp. 842-847 ◽  
Author(s):  
Johannes Zimmer ◽  
Daniel Klein ◽  
Markus Stommel
Keyword(s):  
Process Parameters ◽  
Temperature Drop ◽  
Liquid Product ◽  
Forming Process ◽  
Molding Process ◽  
Influence Of Process Parameters ◽  
Inertia Effects ◽  
Thermally Induced ◽  
Blow Molding ◽  
Stretch Blow Molding

The packaging of liquid products is conventionally realized by using two production stages, which are the stretch blow molding and the filling. In the stretch blow molding process, hot polyethylene terephthalate (PET) preforms are inflated by pressurized air into a cavity to form plastic bottles. In a follow-up process, these packages are filled by a separate machine with the desired liquid product. In contrast to that, liquid-forming combines the blowing and filling stages by directly using the liquid product to form a plastic bottle. Through this substitution, two main challenges arise. Firstly, there are significant inertia effects through the liquid mass, leading to additional reaction forces and a spatially inhomogeneous pressure distribution inside the preform. Secondly, the heat transfer between preform and fluid is drastically increased. Because of this cooling effect, a specific combination of forming speed as well as initial preform and liquid temperatures is necessary to avoid thermally induced preform rupture. This is based on the fact that the formability of PET rapidly declines below its glass transition temperature (Tg). Consequently, a process control requires the knowledge of how the process parameters influence the preform cooling. In this paper, a numerical simulation of the liquid-forming process (LF) is introduced including the preform cooling during forming. In addition, the strain-dependent self-heating effect of PET is implemented. Process experiments under different parameter combinations are conducted using simplified bottle geometry. Through a comparison of the results from experiments and from simulation, the influence of process parameters on the temperature drop and thus on thermally induced failure is determined. In this way, process understanding and control are increased.

Numerical Study of Thickness Distribution of Stretch-Blow Bottles for Defects Prediction

2009 ◽  
Vol 413-414 ◽  
pp. 691-698 ◽  
Author(s):  
Ya Yue Pan ◽  
Shui Ying Zheng ◽  
Xiao Hong Pan
Keyword(s):  
Numerical Study ◽  
Thickness Distribution ◽  
Processing Parameters ◽  
Technological Parameters ◽  
Forming Process ◽  
Molding Process ◽  
Pet Bottles ◽  
Blow Molding ◽  
Stretch Blow Molding ◽  
Good Agreement

Nowadays, polyethylene terephthalate (PET) bottles have been increasingly used as drink containers. They are usually manufactured by a stretch-blow molding process. The improper parameters set in the stretch blow molding process may lead to many defects in the stretch-blow bottle. Finite Element (FE) simulations of the forming process were performed in this paper. The influences of the technological parameters, such as the balance between stretching and blowing rate, the movement of the stretch rod and the inflation pressure, were studied. As a result, the defects, such as over-thin area, cracking and deformation, can be predicted by this method. Especially, it is shown that the cracking in the bottom of products may result from the improper values of the dwell time and the stretch rate. The trends shown by the simulation results are in good agreement with the experimental results. The method can be applied to predict the probable defects, assess the structural properties, and optimize the processing parameters of the stretch blow molding process.

scholarly journals STUDY OF DEFECT ON 180 ML HDPE BOTTLES YOGURT PRODUCTS WITH SMC B11 EXTRUSION BLOW MACHINE AT PT X

KREATOR ◽  
2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Tommy Prasetya Kana ◽  
Handika Dany Rahmayanti ◽  
HM Didik
Keyword(s):  
High Density Polyethylene ◽  
Plastic Material ◽  
Production Cycle ◽  
Molding Process ◽  
Plastic Packaging ◽  
Cycle Times ◽  
Blow Molding ◽  
Plastic Bottle ◽  
Extrusion Blow Molding ◽  
Stretch Blow Molding

The type of plastic packaging that is popular in the community is bottle packaging. The plastic material that is generally used to make plastic bottles is High Density Polyethylene (HDPE). The plastic bottle industry in Indonesia usually uses a blow molding process in its production process, where the blow molding process consists of injection blow molding, extrusion blow molding and stretch blow molding. The SMC B11 machine is one of the extrusion blow molding machines used to produce plastic bottle packaging. In producing workpieces, this machine still produces several products that are not in accordance with company standards, including in terms of production cycle times and product defects. Defects or defects that are often encountered include the appearance of spots, bent parison which causes the bottle to bend (the bottle body is thin one side) and blow pin which causes the thread to not fit.Keywords— Bottle, Plastic, Defect, Extrussion Blow Molding

Thermal Pyrolysis of Polyethylene in Fluidized Beds: Review of the Influence of Process Parameters on Product Distribution

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
K. Suresh Kumar Reddy ◽  
Pravin Kannan ◽  
Ahmed Al Shoaibi ◽  
C. Srinivasakannan
Keyword(s):  
Fluidized Bed ◽  
Process Parameters ◽  
Fluidized Beds ◽  
Pyrolysis Temperature ◽  
Liquid Product ◽  
Product Distribution ◽  
Major Influence ◽  
Process Conditions ◽  
Influence Of Process Parameters ◽  
Thermal Pyrolysis

The present work is an attempt to compile and analyze the most recent literature pertaining to thermal pyrolysis of plastic waste using fluidized bed reactors. The review is short owing to the small number of work reported in the open literature in particular to the fluidized beds. Although works on pyrolysis are reported in fixed beds, autoclaves, and fluidized beds, vast majority of them address to the utilization of fluidized bed due to their advantages and large scale adaptability. The pyrolysis temperature and the residence time are reported to have major influence on the product distribution, with the increase in pyrolysis temperature favoring gas production, with significant reduction in the wax and oil. The pyrolysis gas generally contains H2, CO, CO2, CH4, C2H4, C2H6 while liquid product comprises benzene, toluene, xylene, styrene, light oil, heavy oil, and gasoline with the variations depending on process conditions. The effects of other process parameters, namely fuel feed rate, fuel composition, and fluidizing medium have been reviewed and presented.

scholarly journals Finite Element Analysis of PMMA Stretch Blow Molding

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Afef Bougharriou ◽  
Mohieddine Jeridi ◽  
Mohamed Hdiji ◽  
Anoir Boughrira ◽  
Kacem Saï
Keyword(s):  
Finite Element ◽  
Thickness Distribution ◽  
Geometrical Parameters ◽  
Molding Process ◽  
Element Analysis ◽  
Blow Molding ◽  
Stretch Blow Molding ◽  
Crucial Parameter

The electric bubbles are a useful product made of PMMA material. They are produced by the stretch blow molding process. Thickness, which reflects the quality of the electric bubble, is a crucial parameter that deserves special attention for the molding process. In this work, finite element simulations of the stretch blow molding process are performed aiming at the determination of the preform geometry to ensure homogeneous thickness of the finished product. The geometrical parameters of the preform are optimized allowing a better homogeneity thickness compared to existing data. The predicted parameters allow the improvement of the thickness distribution. The standard deviation of the thickness is reduced to about 95% compared to the existing bubble.

scholarly journals Process Optimization and Implementation of Online Monitoring Process in the Transfer Molding for Electronic Packaging

2019 ◽  
Vol 16 (4) ◽  
pp. 157-175
Author(s):  
Burcu Kaya ◽  
Jan-Martin Kaiser ◽  
Karl-Friedrich Becker ◽  
Tanja Braun ◽  
Klaus-Dieter Lang
Keyword(s):  
Process Parameters ◽  
Process Model ◽  
Online Monitoring ◽  
Molding Process ◽  
Monitoring Method ◽  
Influence Of Process Parameters ◽  
Transfer Molding ◽  
Molding Compounds ◽  
Material Characteristics ◽  
The Impact

Abstract The quality of molded packages heavily depends on the process parameters of the molding process and on the material characteristics of epoxy molding compounds (EMCs). When defects are introduced into the electronic packages in one of the last steps in the manufacturing process, namely, during encapsulation, it may cause high failure costs. To decrease the number of defects due to the molding process, a comprehensive understanding of the impact of process parameters and variations in the characteristics of the EMC on package quality is necessary. This study aimed at supporting a deeper understanding of the influence of process parameters and variations in the material characteristics of the EMC on package quality. A systematic approach was introduced to generate a process model describing the correlation between process parameters and package quality to obtain optimum process parameters for the transfer molding process. The influence of the alterations in material characteristics of the EMC due to prolonged storage duration and humidity on void formation and wire sweep was investigated. An online monitoring method, dielectric analysis (DEA), was implemented into the transfer molding process to monitor the variations in the cure behavior of the EMC. A second molding compound was used to analyze the similarities in the alteration behavior of the molding compounds when subjected to the same preconditioning and to generalize the characteristic information obtained from DEA.

scholarly journals Design and Analysis of Parison Blow Molding Using Adaptive Mesh

2021 ◽  
Vol 9 (VII) ◽  
pp. 1945-1950
Author(s):  
Syed Ayesha Yasmeen
Keyword(s):  
Transient Flow ◽  
Thickness Distribution ◽  
Numerical Data ◽  
Adaptive Mesh ◽  
Time Dependent ◽  
Molding Process ◽  
Pet Bottles ◽  
Blow Molding ◽  
Time Dependent Problem ◽  
Stretch Blow Molding

Blow Molding is one of the most versatile and economical process available for molding hollow materials. When polyethylene is stretched, it exhibits strain-hardening properties, which are temperature, pressure, velocity and strain-rate dependent. In this paper, preform is made by extrusion and forced between two halves by pressurization. This process includes isothermal and transient flow of Newtonian fluid in complex geometries simultaneous with structuring and solidification. A time dependent problem is defined and setting material properties and boundaries condition for bottle blow molding. Numerical data available in POLYDATA for a time dependent problem using ANSYS POLYFLOW were applied. Results display in form contours associated with different variables at different time steps and good agreement with the bottle thickness profile is observed. In this paper, the analysis of the stretch-blow molding (SBM) process of polyethylene terephthalate (PET), parison plastic bottles is studied by the finite element method (FEM). A hyper elastic constitutive behavior was calibrated using material data available in literature in variant high temperatures and strain rates and was used in the numerical simulation. Hydrostatic pressure with convention heat transfer has been used instead of a blowing process. Comparisons of numerical results with experimental observations demonstrate that the model can predict an overall trend of thickness distribution. Through the study, it becomes clear that the proposed model is applicable for simulating the stretch-blow molding process of PET bottles, and is capable of offering helpful knowledge in the production of bottles and the design of an optimum preform.

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