Thermal and Design Sensitivity Analyses for Cooling System of Injection Mold, Part 1: Thermal Analysis

1998 ◽  
Vol 120 (2) ◽  
pp. 287-295 ◽  
Author(s):  
S. J. Park ◽  
T. H. Kwon
Keyword(s):  
Thermal Analysis ◽  
Injection Molding ◽  
Cooling System ◽  
Design Sensitivity ◽  
Sensitivity Analyses ◽  
Injection Molding Process ◽  
Molding Process ◽  
Exterior Surface ◽  
Cad System ◽  
Thermal Analysis Result

In recent years, increased attention has been paid to the design of cooling systems in injection molding, as it becomes clear that the cooling system affects significantly both productivity and part quality. In designing the cooling system of a mold efficiently in terms of rapid and uniform cooling, it would be desirable for mold designers to have an optimal CAD system. For this optimal design, one needs capabilities of both a thermal analysis (to be discussed in Part 1) and a corresponding DSA (to be presented in Part II) for the 3-d mold heat transfer during the cooling stage of an injection molding process. It was found that seemingly negligible inaccuracy in the thermal analysis result sometimes leads to meaningless DSA result. With a successful DSA being an intermediate goal towards optimum design, we have improved the thermal analysis system based on the modified BEM in terms of accuracy and developed rigorous treatments of B.C.s appropriate for DSA by considering the following issues: (i) numerical convergency, (ii) the series solution in part thermal analysis, iii) treatment of tip surface of line elements, (iv) treatment of coolant, and (v) treatment of mold exterior surface. Using two examples, this paper amply demonstrates the importance of these issues.

Thermal and Design Sensitivity Analyses for Cooling System of Injection Mold, Part 2: Design Sensitivity Analysis

1998 ◽  
Vol 120 (2) ◽  
pp. 296-305 ◽  
Author(s):  
S. J. Park ◽  
T. H. Kwon
Keyword(s):  
Cooling System ◽  
Boundary Integral Equations ◽  
Volumetric Flow Rate ◽  
Design Sensitivity ◽  
Boundary Integral ◽  
Sensitivity Analyses ◽  
Bulk Temperature ◽  
Injection Molding Process ◽  
Cooling Channel ◽  
Molding Process

DSA will ultimately play an important role in the design optimization process. Part 2 of this paper presents an efficient and accurate methodology for the DSA of the cooling stage of the injection molding process. The DSA program developed in the present study utilizes the implicit differentiation of the boundary integral equations and the B.C.s presented in Part I with respect to all DVs to yield the sensitivity equations. In this DSA, we have considered various DVs as follows: (i) (DVs related to processing conditions) inlet coolant bulk temperature and inlet coolant volumetric flow rate of each cooling channel inlet, and (ii) (DVs related to mold cooling system design) radius and location of each cooling channel. Two sample problems are solved to demonstrate the accuracy and efficiency of the present DSA formulation and to discuss the characteristics of each DV.

scholarly journals Application of Intelligent Modeling Method to Optimize the Multiple Quality Characteristics of the Injection Molding Process of Automobile Lock Parts

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2515
Author(s):  
Wei-Tai Huang ◽  
Chia-Lun Tsai ◽  
Wen-Hsien Ho ◽  
Jyh-Horng Chou
Keyword(s):  
Temperature Distribution ◽  
Injection Molding ◽  
Process Parameters ◽  
Cooling System ◽  
Injection Molding Process ◽  
Molding Process ◽  
Conformal Cooling ◽  
Characteristic Index ◽  
Average Temperature ◽  
Gray Correlation

This study focuses on applying intelligent modeling methods to different injection molding process parameters, to analyze the influence of temperature distribution and warpage on the actual development of auto locks. It explores the auto locks using computer-aided engineering (CAE) simulation performance analysis and the optimization of process parameters by combining multiple quality characteristics (warpage and average temperature). In this experimental design, combinations were explored for each single objective optimization process parameter, using the Taguchi robust design process, with the L18 (21 × 37) orthogonal table. The control factors were injection time, material temperature, mold temperature, injection pressure, packing pressure, packing time, cooling liquid, and cooling temperature. The warpage and temperature distribution were analysed as performance indices. Then, signal-to-noise ratios (S/N ratios) were calculated. Gray correlation analysis, with normalization of the S/N ratio, was used to obtain the gray correlation coefficient, which was substituted into the fuzzy theory to obtain the multiple performance characteristic index. The maximum multiple performance characteristic index was used to find multiple quality characteristic-optimized process parameters. The optimal injection molding process parameters with single objective are a warpage of 0.783 mm and an average temperature of 235.23 °C. The optimal parameters with multi-objective are a warpage of 0.753 mm and an average temperature of 238.71 °C. The optimal parameters were then used to explore the different cooling designs (original cooling, square cooling, and conformal cooling), considering the effect of the plastics temperature distribution and warpage. The results showed that, based on the design of the different cooling systems, conformal cooling obtained an optimal warpage of 0.661 mm and a temperature of 237.62 °C. Furthermore, the conformal cooling system is smaller than the original cooling system; it reduces the warpage by 12.2%, and the average temperature by 0.46%.

Computer Simulation of Warpage Formation in Polymer Injection Molding of a Step Pad

2006 ◽  
Author(s):  
Sridhar P. Ramamurthy ◽  
Lyle Steenson ◽  
Zhong Hu
Keyword(s):  
Injection Molding ◽  
Cooling System ◽  
Three Dimensional ◽  
Nonlinear Material ◽  
Injection Molding Process ◽  
Molding Process ◽  
Element Analysis ◽  
Polymer Injection ◽  
Fea Model ◽  
Polymer Injection Molding

Warpage is one of the most common defects of a plastic product in the polymer injection molding process. It is attributed to the differential shrinkage after the part is ejected from the die cavity due to the nonlinear material property of the polymer, improper design of the cooling system, geometry of the part and the related process parameters. In this paper, the warpage formation of a plastic part, Step Pad of polypropylene copolymer, in the cooling stage of the polymer injection molding process was simulated by finite element analysis (FEA). A three-dimensional FEA model, taking into account the nonlinear material (polypropylene copolymer) properties, with a thermal-structural sequential coupled approach of higher computing efficiency was developed. The effects of mold closed time and layout of cooling system on the dimension and shape of the part were investigated. Industrial experiments for the different mold closed times (25s, 30s, 35s, 40s, 45s, 50s, and 55s) were conducted. The simulation results were compared with the experimental results. The approach is effective in predicting warpage in the polymer injection molding processes.

Analysis and Optimization on Injection Molding Process of Double Helical Gear Based on Moldflow

2015 ◽  
Vol 1096 ◽  
pp. 376-380
Author(s):  
Chang Yong Jiang ◽  
Hong Lei Shen
Keyword(s):  
Numerical Simulation ◽  
Injection Molding ◽  
Simulation Analysis ◽  
Cooling System ◽  
Process Analysis ◽  
Electrical Equipment ◽  
Helical Gear ◽  
Injection Molding Process ◽  
Feed System ◽  
Molding Process

In view of a kind of a plastic double helical gear in some office electrical equipment, injection molding process analysis was done, by means of Moldflow,to create feed system and cooling system for Moldflow analysis of helical gear, to make numerical simulation analysis, verification and optimization of injection molding process, to obtain some major parameters such as temperature, pressure and time to meet molding requirements of injection molding process of double helical gear.

scholarly journals Study of Injection Molding Process Simulation and Mold Design of Automotive Back Door Panel

2021 ◽  
Author(s):  
Huiwen Mao ◽  
Youmin Wang ◽  
Deyu Yang
Keyword(s):  
Injection Molding ◽  
Cooling System ◽  
Production Cycle ◽  
Injection Molding Process ◽  
Mold Design ◽  
Molding Process ◽  
Element Analysis ◽  
Suitable Material ◽  
Door Panel ◽  
Back Door

Abstract Numerical simulation of the injection molding process of the outer panel of the automotive plastic rear door and mold design is presented here. CATIA is used to design the original automotive steel structure. In order to efficiently design the panels; finite element analysis is used to verify whether the designed parts meet the mechanical properties requirements such as light weight, low fuel consumption, short production cycle, strong modeling design, high corrosion resistance and good recovery. To simulate the injection molding process, CAE software such as ANSYS and HYPERWORKS are used to analyze the back door of the selected material. After the numerical analysis, suitable material is selected, so that the modal and thermodynamic properties of the product could be satisfied as well as improved. In this paper, UG is used to design the convex and concave mold for the injection molding of the automobile’s plastic back door panel. Combined with the characteristics of the parts and the design requirements of the injection mold, the multi-scheme design of the pouring and cooling system is carried out. By comparing the effects of different gating and cooling systems on injection molding, the best gating and cooling system is selected.

Design Sensitivity Analysis Applied to Injection Molding Process: Injection Pressure and Multi-Gate Location Optimization

2000 ◽  
Author(s):  
Kalonji K. Kabanemi ◽  
Jean-François Hétu ◽  
Abdessalem Derdouri
Keyword(s):  
Sensitivity Analysis ◽  
Injection Molding ◽  
Injection Pressure ◽  
Pressure Profile ◽  
Design Sensitivity ◽  
Design Sensitivity Analysis ◽  
Injection Molding Process ◽  
Molding Process ◽  
Filling Fraction ◽  
Design Variables

Abstract In this work, we develop a numerical simulation method to optimize the injection molding process using the design sensitivity analysis (DSA). The optimization concerns the filling stage and focuses on the number and location of gates in a mold cavity as well as the injection pressure, considered as one of the key processing parameters, in order to minimize the fill time. Since the problem to be solved involves transient flow with free surfaces, the direct differentiation method is used to evaluate the sensitivities of the Hele-Shaw, filling fraction and the energy equations with respect to the design variables used in the analysis. The mesh domain parameterization is coped with using B-spline functions. Sensitivity equations are solved by means of finite element method. The proposed numerical approach is combined with the sequential linear and quadratic programming method of the DOT optimization tools to find the new design variables at each iteration. Starting with any initial gate locations and injection pressure profile, the method enables us to find the optimal gate locations together with the optimal injection pressure profile. Finally, numerical results involving complex mold geometries are presented and discussed to assess the validity and robustness of the proposed method.

CAE of Mold Cooling in Injection Molding Using a Three-Dimensional Numerical Simulation

1992 ◽  
Vol 114 (2) ◽  
pp. 213-221 ◽  
Author(s):  
K. Himasekhar ◽  
J. Lottey ◽  
K. K. Wang
Keyword(s):  
Heat Transfer ◽  
Heat Exchange ◽  
Injection Molding ◽  
Cooling System ◽  
Three Dimensional ◽  
Ambient Air ◽  
Injection Molding Process ◽  
Analysis Tool ◽  
Molding Process ◽  
Dimensional Boundary

In recent years, increased attention has been paid to the design of cooling systems in injection molding, as it became clear that cooling affects both productivity and part quality. In order to systematically improve the performance of a cooling system in terms of rapid, uniform, and even cooling, the designer needs a CAE analysis tool. For this, a computer simulation has been developed for three-dimensional mold heat transfer during the cooling stage of an injection molding process. In this simulation, mold heat transfer is considered as cyclic-steady, three-dimensional conduction; heat transfer within the melt region is treated as transient, one-dimensional conduction; heat exchange between the cooling channel surfaces and coolant is treated as steady, as is heat exchange with the ambient air and mold exterior surfaces. Numerical implementation includes the application of a hybrid scheme consisting of a modified three-dimensional, boundary-element method for the mold region and a finite-difference method with a variable mesh for the melt region. These two analyses are iteratively coupled so as to match the temperature and heat flux at the mold-melt interface. Using an example, the usefulness of the simulation developed here in the design of a cooling system for an injection molding process is amply demonstrated.

Sign in / Sign up

Export Citation Format

Share Document