The ejector system design is one of the crucial activities of die-design for die-casting dies. It involves determination of the ejection area, area of ejecting pins, no. of ejector pins and at last placement of ejector pins. Traditionally, a die-casting engineer uses his knowledge and experience along with information like part design, no. of cavities, gating system and process parameters to determine ejection system parameters for a die-casting part. The part CAD model parameters are then used to model the ejection system for the die-casting part. Thereafter, the ejection system design for the die-casting part is tested using ejection simulations.
The necessary modifications in the ejection system design are made till the desired results are obtained. This makes the process iterative and time-consuming. This paper presents an algorithm that would help in automatic design of the ejector system. The proposed algorithm is able to calculate the ejecting area, area of ejection pins, number of ejection pins and placement of ejection pins on the part. To demonstrate the capabilities of the proposed algorithm we have to determine the parameters the parameters of case study using the MATLAB 7.0. The result from the case study is quite encouraging and is in-line with the best industry practice.
Contents
1. INTRODUCTION
2. LITERATURE REVIEW
2.1. Identification of Undercut Feature
2.2. Parting Line Determination
2.3. Cavity Layout and Gating System Design
2.3. Side-Core Design
3. RESEARCH GAPS
4. OBJECTIVES OF THIS ARTICLE
5. COMPUTER-AIDED DESIGN OF DIE-CASTING
5.1. Data Initialization
5.2. Identification of Undercut Features and Design of Side Cores
5.3. Determination of Parting Line
5.4. Cavity Layout Design
5.5. Gating System Design
5.6. Ejector System Design
6. IMPLEMENTATION AND RESULTS
7. CONCLUSION
8. References
AN ALGORITHM FOR COMPUTER-AIDED EJECTOR DESIGN FOR DIE-CASTING DIES
ROHIT KUMAR, Dr. Ranjit Singh, Dr. Sukhwinder Singh Jolly
Department of Mechanical Engineering, Sri Guru Granth Sahib World University Fatehgarh Sahib, 140406, India.
Abstract: The ejector system design is one of the crucial activities of die-design for die-casting dies. It involves determination of the ejection area, area of ejecting pins, no. of ejector pins and at last placement of ejector pins. Traditionally, a die-casting engineer uses his knowledge and experience along with information like part design, no. of cavities, gating system and process parameters to determine ejection system parameters for a die-casting part. The part CAD model parameters are then used to model the ejection system for die-casting part. Thereafter, the ejection system design for the die-casting part is tested using ejection simulations. The necessary modifications in the ejection system design are made till the desired results are obtained. This makes the process iterative and time consuming. This paper presents an algorithm that would help in automatic design of ejector system. The proposed algorithm is able to calculate the ejecting area, area of ejection pins, number of ejection pins and placement of ejection pins on the part. To demonstrate the capabilities of proposed algorithm we have determine the parameters the parameters of case study using the MATLAB 7.0. The result from case study is quite encouraging and is in-line with the best industry practice.
Keywords: Die-Casting Dies, Gating System, Die Design, Ejecting Area, Ejection Pins
1. INTRODUCTION
Die design is most crucial process in which usage of both die-designer expert knowledge and computer system knowledge is used. Die designing mainly of two type’s i.e. traditional die-casting die designing and computer-aided die casting die design. In traditional die-casting die design involves manually design of die casting die design with a limited use of computer. The die-casting die parameters are selected by the die engineer individually as requirements of the parts and die-casting die. On the other hand in computer-aided die-casting die design involves the design of die-casting die design using the CAD model of the part and computer system with a limited interference of human. The die-casting die parameters are selected by the computer system by itself or can be user defined.
The role of CAD/CAM tools for die-design has become important to keep pace with the latest technology, demand for low cost, high quality, and fast delivery. Although, CAD/CAM tools are very useful in preparing CAD model of a die-casting part, they missed many aspects. The molding tool applications of available CAD/CAM systems allow the user to use their functionalities for preparing CAD models of different components or parts of the die casting die.
The die-casting die-design involves several non-trivial tasks. Fuh et al. 1 identify seven major steps of computer-aided die-casting die-design which are setting shrinkage and draft, determining the cavity number and layout, designing the gating system, designing the die-base, parting design, designing the side-core mechanism, and ejector & cooling system design. In setting shrinkage and draft, we know that as the molten metal contracts during solidification, the original die-casting part geometry must be scaled by a certain factor to reflect the material shrinkage. While cavity number and layout are determined based on the part shape and dimension, machine type, machine size lamination, machine clamping force, machine pumping capacity, etc. In gating system design flow paths and filling conditions are analyzed. The type of gate, size of gate and location of the gate, runner and overflow are also determined in accordance with the geometry of the part and cavity layout of part to achieve proper filling in the whole die cavity. In Die base design, with the cavity number and cavity layout decided, a suitable die-base is selected to accomplish the proposed layout. The criterion normally used in creating the overall size of the die-base is that the ejector plate must totally cover or contain all of the cavity area within its bounds. Parting design is to create parting surfaces along the selected parting lines and eventually split the containing box into two halves, a core block and a cavity block, in which the negative imprint of the die-casting part is made. In side core mechanism designing if the die-casting part has any undercut, which will block the die halves from opening, moving cores and angled pins designed to facilitate the die opening and the elimination of die-casting from the die. Ejection and cooling system design both are essential feature of a die-casting die. Ejection system design is composed of designing and placing the ejector pins on precise place to eject the part from the die and while ejecting the part the ejector pin should keep the part from bending due to stress and forces. Although, in cooling system design set of waterlines drilled within the dies and inserts that conduct the heat away from the die cavity. The cooling system should be positioned and size properly so as to achieve rapid and uniform cooling without interfering with the ejection system and moving core mechanism.
The design of ejection system is crucial for ejection of the die. There are a number of factors which affect the design of ejection system. It is often tiresome for a die design engineer to design and decide the optimum placement of the ejectors pins of the ejection system. Present automatic systems on ejection system lack the level of automation. Proposed work would concentrate on acquiring the knowledge of die-casting engineer into a system and use it for automated ejection system design.
Ejectors are mold and die components with which the casting is extracted from the cavity. Sometime ejector pin marks are raised or depressed on some parts, or larger part may be need more tolerances for proper ejection of the part, or sometime ejector pins marks are surrounded by flash of metal and necessary removal of this flash can be produces by proper ejection system design. It is important to place the ejectors avoid distortion and to improve the part release.
The idea is to make sure that each part of the casting or molded part surface releases from the cavity surface exactly at the same time. Some plastic materials are flexible and the distortion is reversible. In some cases it is possible to eject parts with snap fit system without any moving core mechanisms. There are different shape ejectors. The cheapest and most common type is round. Another common, but more expensive type is flat rectangular ejector. These are commonly used on top of ribs if ejection bosses are not allowed. If there is a need to hide ejection marks as invisible as possible or solve some special ejection problems, the designer may select a sleeve ejector or ejection plate.
However, much needed design knowledge and automation of design steps especially for the die-design of ejection system design in die casting is lacking.
As undercut feature or side core design, no. of cavity determination and layout design, gating system design, parting line design are most crucial part of a die designing. In next sections available literature review on above parts is given. After literature review the research gaps coming through them and objective of the work is given. After that, computer-aided die designing is discussed in detail, the ejector system design and case study is given. At last the conclusion and the references are given.
2. LITERATURE REVIEW
In this section literature review on the general topics of the die-casting i.e. identification of undercuts features, parting line determination, gating system design and side core design is presented. Research gaps also discussed at the end of this section. Some of the literature charted is discussed in below paragraphs.
2.1. Identification of Undercut Feature
Singh et. al. 2 proposed a method for automated identification of the undercut feature and design of side-cores for a die-casting part which depends on part geometry and process requirements. The proposed system uses the data from a B-rep neutral file and detection of undercut feature is affected by the parting direction which is chosen by the user and is input into the system. Various steps that are involved in automatic detection of undercut features are classification of surfaces of the part, determining non-convex surfaces and checking their accessibility. The system can be improved so that undercut features with higher level of complexity could also be taken into account.
Zhang et al. 7 present an approach for free form feature extraction from molded parts. The faces of the part are first classified into six curvature regions on the basis of Gauss and mean curvature. The undercut features composed of depression, and protrusion features are then determined on the basis of type of their curvature regions. The withdrawal direction for each undercut feature is determined by computing visibility maps for the undercut features.
Woo 8 presented a methodology to determine the visibility of a part which is mapped on to a unit sphere. The visibility hierarchy was presented wherein the visibility of a point, line, and surface were discussed. The visibility hierarchy was then discussed with its implementation on different manufacturing process. These manufacturing processes were classified into point, line and surface visible processes.
Ye et al. 15 presented a method to recognize isolated and interacting undercut features. An undercut feature is defined by an undercut sub-graph. After recognizing undercut features a Boolean operation is used to generate the side core for each under cut. The method was implemented using ANSI C language. A case study of a hand phone was taken to implement the method. The program is capable of generating side cores form identified undercut features. The undercut feature recognition was limited.
2.2. Parting Line Determination
Chen et al. 3 present an algorithm to determine the parting direction. It finds the minimum volume bounding box for a part’s 3-D model and takes its three orthogonal directions as the candidate parting directions. It uses the block factor to measure number of undercuts in a given parting direction. The selection of parting direction is based on three criteria: (i) draw factor, (ii) blocking factor and (iii) projected area of the part. Fuzzy representation is applied to select best parting direction using the selection criteria.
Madan et al. 5 propose a method to evaluate the parting direction from available alternatives for die-cast parts. They developed a selection criterion, which uses eleven influencing factors related to part geometry and the die-casting process for selection of parting direction.
Khardekar et al. 6 present an algorithm to find the feasible mold parting directions using a tessellated part model. The tessellated part model is defined by its triangular facets. The facets are classified as up-facets and down-facets. The system detects the undercut features by searching any partially or completely invisible up-facets in a given parting direction. Thereafter, the undercut free directions are determined. The algorithm performs the draft analysis wherein necessary draft is applied to the vertical facets for easy removal of the part from the mold. The algorithm is limited to the parts moldable with two piece mold. The algorithm cannot be applied on the parts requiring side-cores or a multi-piece mold.
Singh et. al. 9 proposed a method for automated determination of the parting line for die-cast parts based on identification of undercuts, protrusions and classification of part surfaces, identification of parting line regions, and determination of the parting line. The system is able to generate a number of parting lines in the selected parting direction after applying the die-casting process requirements. The optimal parting line is determined from the different parting lines options. The system can further be improved by exploring the possibility of multiple stepped, tapered and compound parting lines, and intersecting undercuts and protrusions.
2.3. Cavity Layout and Gating System Design
V. Kumar et. al. 10 proposed a systematic approach for cavity layout design using some details of the part geometry.
First stage consists of determining the number of cavities considering technical, economical, time and geometrical limitations. Second stages provides a possible solution for layout pattern, which is based on the number of cavities and uses a knowledgebase of layout patterns. Once the layout pattern has been selected, third stage of the system arranges the individual cavities by selecting a suitable die base. Selection of die base takes into account the clearances required to accommodate feeding system, side pulls and is based on the die design knowledge base.
Ferencz et al. 12 used cavity filling simulations to optimize design of a gating-system of various types. Gating-system configurations for most commonly used gating-system designs are proposed. Moreover, the ideal shape of the runner connections are also proposed. A brief procedure for gating design is also presented. Thereafter, the industry recommended overflow design is presented. Finally, the flow simulation for the gating-system and part design optimization is done. It is concluded that the selection of a gate is an iterative activity which requires a lot of expertise.
Singh et al. 13 proposed a computer aided system for gating-system for die-casting die-design with multi-gates which helps to generate parameters of the multi-cavity die taking into account a multitude of factors, such as part design, material properties, process data and die-casting machine information. The parameters so generated are applied on selected gating-system feature existing in the library to complete the design of gating-system. The system generated results for industrial case-study parts are in tandem with the industry practices.
Kumar et al. 14 proposed a system which applies design knowledge and rules, accounting for various influencing factors to design gating system element and casting process and generate their computer-aided design models in the an efficient manner. To develop the system for the gating system design they used SOLIDWORKS CAD software using its API with programming in Microsoft VB.NET and also demonstrate the capabilities of the developed system by industrial case study, but it is limited to single gating system design for multi cavity dies.
2.3. Side-Core Design
Yin et al. 4 propose a method for moldability analysis of near-net-shaped parts. They employed freedom cones which represent the aggregate of all the possible translation directions of a part. The freedom cones for internal and external undercuts are determined independently. The pair of parting directions, which minimizes the number of side-cores is selected.
Yue et al. 11 proposed an integrated CAD/CAE/CAM system for die-casting die-design, simulation, and manufacturing. The system works in three phases. The first phase deals with CAD modeling of the die-casting part and the die-casting die. CAD data of the part model is used along with the empirical equations to determine die-casting process parameters. A die-casting expert system is used to determine the die parameters, which are used to generate CAD models of the die. In the second phase simulation runs are performed to check proper filling of the die. The results from the simulation are observed and influencing factors are regulated. The optimized design is communicated to the last phase which deals with manufacturing of the die.
Fu 16 presented the application of surface de-moldability and moldability to design the side cores for plastic injection molding process. The surfaces of the part were classified as core-molded, cavity molded and side core molded. Then the side core surfaces were grouped into different undercut feature. Further De-moldability Maps (De-maps) were determined for each undercut and the Most Preferred De-Molding Direction (MPDD) was defined. Then the undercut features with same MPDD were grouped so that they can be molded by same side core.
3. RESEARCH GAPS
From the literature review, it is concluded that despite very useful previous work, automation in ejection design has not got due attention. The research gaps in the previous research are mentioned below:
- The level of automation for data initialization is limited
- The level of automation in ejection design is not according to the process requirements
- Frame work for automated die-design needs enhancement
4. OBJECTIVES OF THIS ARTICLE
This article addresses the research gaps mentioned in the previous section. Proposed work emphasis on design-manufacturing integration of die-casting process. It has been intended to present a system that would employ the knowledge of a die-casting engineer to address data initialization, ejection design system for a computer-aided die design. Accordingly following objectives have been identified for present research work.
- Automatic data initialization from the part data
- Automated design of ejection system
- Frame work for computer-aided of die-casting die-design
5. COMPUTER-AIDED DESIGN OF DIE-CASTING
A computer-aided system for die-casting die design has been presented in this section. The idea to present this system is to present a methodology by which design of die-casting die can be realized with minimum effort, in a short time alongside achieving consistency in the decision making at different stages of die-casting die-design. The proposed system comprises nine modules/systems named as: (1) data initializing, (2) identification of undercut features and design of side-cores, (3) determination of parting line, (4) core and cavity design, (5) cavity layout design, (6) gating-system design (7) die-base design, (8) ejection-system design, and (9) cooling-system design. Following paragraphs briefly explain the architecture and modules of the system.
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Figure 1.: Computer-Aided System for Die Design
5.1. Data Initialization
This module pertains to extracting and providing requisite information related to geometry and material from the die-casting part model along with some die-design parameters, such as die material properties, die-casting alloy properties, and pouring temperature. The important characteristics that are extracted from the part are weight, volume, and average wall thickness. Some other information such as parting direction, number of gates, and the die-casting machine selection are provided by the user. The part information extracted from its CAD model is saved as an MS Excel file. The level of automation in data initialization may be increased by implementing the system as an add-on application in some commercially available CAD software.
5.2. Identification of Undercut Features and Design of Side Cores
In any automated system for die-casting die design, identification of undercut features is a prerequisite. A number of systems exist in the literature that help identify undercut feature for die-casting. Madan et at 5 developed a methodology to identify undercut features. However, in die-casting parts complex undercut features are often present that cannot be withdrawn in a single direction. Such undercut features therefore need to be divided, so that they can be withdrawn with the help of more than one side-cores.
The system for identification of undercut features of the integrated framework automatically identifies undercut features that include complex undercut features. Furthermore, the system also provides a methodology to divide them into simple undercut features for facilitating side-core design. Detailed methodology of the system has been described by the authors in Singh et al. 2.
5.3. Determination of Parting Line
The system makes use of the system for determination of parting line, developed by Singh and Madan 9. The brief highlights of the system are discussed below:
(a) It identifies the core and cavity side of the part.
(b) The core-cavity surfaces are given due consideration in selecting the parting line.
(c) Effect of the undercut features present on core-cavity surfaces of the die-casting part is accounted for.
(d) Effect of the protrusion features present on core-cavity surfaces of the die-casting part is considered.
(e) Splitting of parting lines when it encounters an undercut is taken care-of.
(f) Determination of parting line options in a given parting direction.
(g) The parting line is selected from the feasible options following a decision criterion, which is based on a number of factors, such as dimensional stability and draw distance.
5.4. Cavity Layout Design
The system for cavity layout design determines the number of cavities and their layout in the die-base. The system makes use of a system developed by Kumar et al 10 to determine the number of cavities and their layout. The system make use of the information such as part information, material properties and production data, and die-casting machine parameters for determination of number of cavities. It determines both the number and layout of cavities automatically. Furthermore, capabilities of the cavity design may be improved by enhancing the cavity layout arrangements.
5.5. Gating System Design
The gating system is a channel or a passage in the die through which the molten metal reaches the cavities. The gating system design refers to the design of its various elements, such as gate, runner, overflow, and biscuit etc.
This section discusses the developed methodology for the gating-system design followed in the system. It is known fact that a variety of die-casting parts made by the manufacturing industry that have large variations in their size and shape. Therefore, gating-system for a die is custom designed for the die-casting part keeping in view a number of factors. The methodology of the proposed system developed by Singh et al 17 follows below mentioned four steps.
- Determine the die-casting process parameters.
- Determine gating-system parameters.
- Generate CAD models of gating-system features using the feature library, and
- Assemble the gating-system with CAD model of other parts of the die.
5.6. Ejector System Design
Ejectors are mold and die components with which the casting is extracted from the cavity. Ejectors places leave round, rectangular or similar clearly visible marks to the casting surface. For this reason the side of the casting, from which the ejection takes place, should be non-visible in the final product.
It is important to place the ejectors avoid distortion and to improve the part release. Typical places to place ejector are:
- On top of the cooling or strengthening ribs.
- Either near outside of a small core or on top of a small core.
- On the sides of large flat surfaces.
- On top of large area core near the sides.
- Not in the middle of large surfaces.
- Best place for the ejectors are on top of the ribs.
- Blade ejectors are over ten times more expensive than common round ejector pins.
- Ejectors are wearing parts that need constant replacement.
The idea is to make sure that each part of the casting or molded part surface releases from the cavity surface exactly at the same time. Some plastic materials are flexible and the distortion is reversible. In some cases it is possible to eject parts with snap fit system without any moving core mechanisms.
There are different shape ejectors. The cheapest and most common type is round. Another common, but more expensive type is flat rectangular ejector. These are commonly used on top of ribs if ejection bosses are not allowed. If there is a need to hide ejection marks as invisible as possible or solve some special ejection problems, the designer may select a sleeve ejector or ejection plate.
6. IMPLEMENTATION AND RESULTS
Ejector systems operate mechanically when the ejector pins stop while the ejector or moving platen continuous to move the cavity back and away from the casting. The ejector plate is drilled to accept the desired pattern of ejector pins. Ejector pins are commercially available in standard sizes with a head on one end. The purpose of the back plate is to contain the pins so the same pattern is drilled into it blind with whole sizes to accept the heads. A pattern of large diameter bumper pins is placed in the back platen of the casting machine to stop the movement of the ejector plate, while the dies continue to move apart. The length of the bumpers is designed to stop the ejector plate at the start of ejection.
As the ends of the ejector pins stop, so does the cast shot. As the ejector cavity continues to move away, the shot is cleared from the cavity so it can be extracted or dropped to a conveyor belt and transported to the trim operation. The ejector plates are separated from the die retainer by rails which should be located top and bottom and on both sides to keep normal debris out of the ejector mechanism. These rails must be at least 2 in. wide. However, since they are pressed into the ejector platen, the mounting area is best calculated, as discussed in the following lines, to minimize the concentration of locking pressure upon this area.
The detailed algorithm for the design of ejector system design is given in Figure 2. In this first of all system extract part related information from its CAD model and make use of databases of die-casting machines and materials. Furthermore for determining the ejecting area we use the data from system for parting line as discussed above in section 5.3. After that using the different formulas as given below, total ejecting area, area of ejecting pins, no. of ejection pins required are determined which are important parameters of the ejection system design. After determining the required parameters, the type of ejector pin is chose as requirement from the ejector database. Finally, the ejector pin placement on the part is made depending upon the data taken from the system for side-core design and hence, the ejector system design takes place.
i. Assuming ejection area to be 4% of the area of the casting
ii. Total Ejecting area = Projected area of Component*4%
iii. Selected Ejector Pin Diameter = D
iv. Area of Ejector Pins = ( П*D2 ) / 4
v. No. of Ejector Pins Required = Total Ejection Area / Area of Ejection Pin
Abbildung in dieser Leseprobe nicht enthalten
Figure 2.: Algortihm of ejector systen design
For implementing the above algorithm we have taken a case study of a part as shown in Figure 3. The calculations which are taken place for calculating the required parameters using MATLAB 7.0 are shown in table 1. In figure 4, the ejector pin design is shown having same parameters as calculated before designed in SOLIDWORKS 2016, and type of pin is chooses from the given database. The result from case study is quite encouraging and is in-line with the best industry practice.
Table 1.: Calculations of No. of Ejector pin required for case study
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Abbildung in dieser Leseprobe nicht enthalten
Figure 3.: Case study part
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Figure 4.: Ejector Pin Design
7. CONCLUSION
This paper presents an algorithm for computer-aided die-design for die casting parts, wherein, an attempt is made to develop system that help in important phases of the die-casting die-design. Design of a die-casting die also requires other components of the die to be designed, such as parting line identification, ejection systems and cooling systems. In fact, design of a die is not complete until all such components are designed and assembled with the die. The systems extract part related information from its CAD model and make use of databases of die-casting machines and materials. Furthermore, the systems prompt the user to input other information pertaining to few part characteristics (such as type of ejector pin) and apply industry best practices, rules and guidelines to help identify number of ejector pins, their placement and ejector system design for the die casting dies.
8. References
1. S. Kalpakjian and S. R. Schmid, Manufacturing Engineering and Technology. India: Prentice Hall, 2005.
2. Singh, Ranjit, Jatinder Madan, and Rajesh Kumar. "Automated identification of complex undercut features for side-core design for die-casting parts." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 228.9 (2014): 1138-1152.
3. Y. H. Chen, Y. Z. Wang, and T. M. Leung, “An investigation of parting direction based on dexel model and fuzzy decision making,” Int. J. Prod. Res., vol. 38, no. 6, pp. 1357–1375, 2000.
4. Z. P. Yin, H. Ding, and Y. L. Xiong, “Mouldability analysis for near net shaped manufacturing parts using freedom cones,” Int J Adv Manuf Technol., vol. 16, pp. 169–175, 200AD.
5. J. Madan, P. V. M. Rao, and T. K. Kundra, “Die-casting feature recognition for automated parting direction and parting line determination,” J. Comput. Inf. Sci. Eng., vol. 7, no. 3, pp. 236–248, 2007.
6. R. Khardekar, G. Burton, and S. McMains, “Finding feasible mold parting directions using graphics hardware,” Comput. Des., vol. 38, pp. 327–341, 2006.Singh, Ranjit, and Jatinder Madan. "Systematic approach for automated determination of parting line for die-cast parts." Robotics and Computer-Integrated Manufacturing 29.5 (2013): 346-366.
7. Y. C. Nee, M. W. Fu, J. Y. H. Fuh, K. S. Lee, and Y. F. Zhang, “Automatic determination of 3-D parting lines and surfaces in plastic injection mould design,” Ann. CIRP, vol. 47, no. 1, pp. 95–98, 1998.
8. T. C. Woo, “Visibility maps and spherical algorithms,” Comput. Des., vol. 26, no. 1, pp. 6–16, 1994.
9. Singh, Ranjit, and Jatinder Madan. "Systematic approach for automated determination of parting line for die-cast parts." Robotics and Computer-Integrated Manufacturing 29.5 (2013): 346-366.
10. Kumar, V., J. Madan, and P. Gupta. "System for computer-aided cavity layout design for die-casting dies." International Journal of Production Research50.18 (2012): 5181-5194.
11. Yue, Shuhua, et al. "Application of an integrated CAD/CAE/CAM system for die casting dies." Journal of Materials Processing Technology 139.1-3 (2003): 465-468.
12. P. Ferencz, G. Lucian, S. Ioan, and C. Cristian, “Studies concerning the design of the runner, gate and venting systems in the case of the high pressure die-casting technology,” Ann. oradea Univ. fascicle Manag. Technol. Eng., vol. IX, no. XIX, p. 3.177-3.183, 2010.
13. Singh, Ranjit, Rajesh Kumar, and Jatinder Madan. "A Systematic Approach for Computer-Aided Gating-System Design for Die Casting Dies." ASME 2016 11th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2016.
14. Kumar, Vijay, and Jatinder Madan. "A system for computer-aided gating design for multi-cavity die-casting dies." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 231.11 (2017): 1983-1999.
15. Ye, X. G., J. Y. H. Fuh, and K. S. Lee. "Automatic undercut feature recognition for side core design of injection molds." Journal of Mechanical Design126.3 (2004): 519-526.
16. Fu, M. W. "The application of surface demoldability and moldability to side-core design in die and mold CAD." Computer-Aided Design 40.5 (2008): 567-575.
17. Singh, Ranjit, Rohit Kumar, and Sukhwinder Singh Jolly. "A computer-aided approach for gating system design for multi-cavity dies." (2017).
Frequently asked questions
What is the main topic of "AN ALGORITHM FOR COMPUTER-AIDED EJECTOR DESIGN FOR DIE-CASTING DIES"?
The paper focuses on presenting an algorithm for automatic design of the ejector system in die-casting dies, aiming to improve automation and efficiency in the die-design process.
What are the key components of the proposed algorithm?
The key components include calculating the ejecting area, area of ejection pins, number of ejection pins, and placement of ejection pins on the part, using the part's CAD model and die-casting parameters.
What are the main objectives of this article?
The objectives are: automatic data initialization from part data, automated design of the ejection system, and providing a framework for computer-aided die-casting die-design.
What are the different steps of computer-aided die-casting design described in the article?
The steps include: data initialization, identification of undercut features and design of side cores, determination of parting line, core and cavity design, cavity layout design, gating-system design, die-base design, ejection-system design, and cooling-system design.
What is data initialization in the context of this article?
Data initialization involves extracting and providing information related to geometry and material from the die-casting part model, along with die-design parameters such as die material properties, die-casting alloy properties, and pouring temperature.
What are the key considerations for ejector system design?
Key considerations include determining the ejection area, number of ejector pins required, optimal placement to avoid distortion, and choosing the appropriate type of ejector pin (e.g., round, rectangular, sleeve ejector).
What research gaps does this article address?
The article addresses the limited automation in data initialization, lack of automation in ejection design according to process requirements, and the need for enhancement in the framework for automated die-design.
How is the parting line determined in the proposed system?
The system identifies the core and cavity side of the part, considers core-cavity surfaces, accounts for undercut and protrusion features, handles splitting of parting lines, determines parting line options, and selects the optimal parting line based on factors like dimensional stability and draw distance.
What is the significance of the gating system design in die-casting?
The gating system design is crucial as it's the channel through which molten metal reaches the cavities, influencing the filling conditions and the quality of the die-cast part. It involves designing elements like the gate, runner, and overflow.
What are the benefits of using a computer-aided ejector design?
Benefits include reducing the time and effort required for die-design, improving consistency in decision-making, optimizing ejector placement to prevent part distortion, and ultimately enhancing the quality and efficiency of the die-casting process.
What is the algorithm for ejector system design?
The algortihm consists of extracting part information, calculating ejecting area, determining total ejecting area, selecting ejector pin diameter, calculating area of ejector pins, finding the number of ejector pins required, choosing the type of ejector pin, and finally, placing ejector pins on the part.
- Quote paper
- Rohit Kumar (Author), Dr. Ranjit Singh (Author), Dr. Sukhwinder Singh Jolly (Author), 2020, CAD for Die-Casting. An Algorithm For computer-Aided Ejector Design, Munich, GRIN Verlag, https://www.grin.com/document/997073
