Gating System Design Research Articles

Effect of Casting Design to Microstructure and Mechanical Properties of 4 Mm Twdi Plate

Casting design is chosen by Soedarsono et al to maintain cooling rate in producing thin wall ductile iron (TWDI). Cooling rate should be maintained to prevent carbide formation. This paper discusses the effect of gating system design on microstructure and mechanical properties of 4 mm TWDI plate. A casting design based on vertical gating system is made to produce TWDI plates with the thickness of 1, 2, 3, 4, and 5 mm. This vertical system allows plates to function as runner which will helps in preventing premature solidification. Three designs were made. These designs are coded as T1, T2, and T3. These three designs were also used in making 1, 2, 3, and 5 mm TWDI plates of which the result has been published. Z-Cast is used to conduct a casting design simulation for filling flow and solidification. The result of flow simulation shows that the filling flow is resulted in two kinds. The result of solidification specifies that the 4 mm TWDI plates solidify in the third place. The result of the experiment highlights that in all of the designs, which have microstructure and consisted of nodule graphite in ferrite matrix, no trace of carbide and skin effect are formed. The length of skin effect varies in all of the designs. The highest nodularity is only 80% while nodule count is 931 nodules/mm2. Brinell hardness number for all of the design is beyond the standard given by JIG G5502. As for UTS, yield strength and elongation none of the designs exceeds the minimal standard. The result of the experiment does not confirm the result of the simulation. In sum, compared to the previous result, the curve trends of 4 mm TWDI plates look similar to 2 mm TWDI plates.

Effect of Casting Design to Microstructure and Mechanical Properties of 2 Mm Twdi Plate

It is important to strictly maintain the cooling rate in producing thin wall ductile iron (TWDI) to prevent carbide formation. There are many ways to control cooling rate whereas casting design is the most independent one. This paper discusses the effect of gating system design on microstructure and mechanical properties of 2 mm TWDI plate. A casting design based on vertical gating system is made to produce TWDI plates with the thickness of 1, 2, 3, 4, and 5 mm. This vertical system allows plates to function as runner. This situation helps in preventing premature solidification. There are three designs in which they are coded as T1, T2, and T3. These three designs were also used in making 1, 3, and 5 mm TWDI plates of which the result has been published. Z-Cast is used to conduct a casting design simulation for filling flow and solidification. The result of flow simulation shows that the filling flow is resulted in two kinds. The result of solidification specifies that in T1 and T2 the 2 mm TWDI plates solidify in the same time as 1 mm TWDI plate. Furan sand was used as moulds in the experiment. The result of the experiment highlights that in all of the designs, which have microstructure and consisted of nodule graphite in ferrite matrix, no trace of carbide and skin effect are formed. The length of skin effect varies in all of the designs. The highest nodularity is only 86% while nodule count is 1344 nodules/mm2. Brinell hardness number for all of the design is beyond the standard given by JIG G5502. As for UTS and elongation none of the designs exceeds the minimal standard. The result of the experiment does not confirm the result of the simulation. In sum, compared to the previous result, the curve trends of 2 mm TWDI plate combine the curve trends of 1 and 3 mm TWDI plates.

Casting Defect Analysis using Design of Experiments (DoE) and Computer Aided Casting Simulation Technique

In this paper the design of experiments and computer assisted casting simulation techniques are combined to analyze the sand related and methoding related defects in green sand casting. An attempt has been made to obtain the optimal settings of the moulding sand and mould related process parameters of green sand casting process of the selected ductile iron cast component. The green sand related process parameters considered are, moisture content, green compression strength, and permeability of moulding sand and mould hardness (in horizontal direction). In first part of this paper Taguchi based L18 orthogonal array was used for the experimental purpose and analysis was carried out using Minitab software for analysis of variance (ANOVA) and analysis of mean (AOM) plot. ANOVA results indicate that the selected process parameters significantly affect the casting defects and rejection percentage. In the second part, shrinkage porosity analysis is performed using casting simulation technique by introduction of a new gating system designed, solid model developed for four cavities mould. Number of iterations using casting simulation software was performed for mould filling and solidification analysis to reduce the level and intensities of shrinkage porosities in cast component. With new gating and feeding system design reduction in shrinkage porosity (about 15%) and improvement in yield (about 5%) is observed.

Computer aided design of gating system for a die-casting die

Design of gating system of a die-casting die is a non-trivial task, which depends on a number of parameters influenced by part design and die-casting alloy. Today, a lot of CAD/CAM tools are used for design, development and manufacturing of die-casting dies. However, design of a die-casting die and its gating system, still depend on a die-casting expert and require lot of time. Present work is about computer-aided design of gating system for die-casting die. System proposed in this paper takes CAD file of the die-casting part as input and uses process knowledge to determine different parameters of the gating system. Design of various components of the gating system, namely runner, gate and overflow is attempted. A feature library is proposed, which together with parametric design, generates CAD model of the components of the gating system. The system would be useful to bridge the gap between design-manufacturing integration for die-casting.

Optimal gating system design for investment casting of sterling silver by computer-assisted simulation

The first requirement of all casting processes is complete filling without any defects after solidification. However, casting defects often occur in casting processes, especially incomplete filling. The causes of incomplete filling are related to poor gating system, incorrect pouring, and molding temperature. A suitable shape and dimension of gating system will increase the melt flow while it is feeding into mold cavity by eliminating excessive pouring and molding temperature. The objective of this study is to develop a new design of gating system for eliminating incomplete filling. The new shape and dimension of pouring cup, main sprue, and sprue base are proposed and investigated. The computational flow model is solved with the aid of computer simulation. The targets of an optimum solution are increasing the efficiency of metal flow and reducing turbulence. The experiments are conducted to validate the simulation data. The results of this study will aid in the elimination of casting defects and increase the productivity.

Mold Design Optimization for Sand Casting of Complex Geometries Using Advance Simulation Tools

Defects data and design optimization of gating system are a great challenge in casting. Most significant factors contributing to the volumetric changes and defects are pouring temperature, time, filling pattern, gating system, and casting geometry. The optimized design of gating system facilitates the smooth filling of the mold without air entrapment, material flow hindrance. Conventionally, the foundry method includes design calculations, best practices, and the tedious hit-and-trial method to get the optimum design of pattern/mold for defect-free casting. The design iterations and improvements directly affect the development cost and time, and one of the great challenges of the foundry method is to reduce this time and cost. The numerical simulation techniques embedded in casting simulation software are a powerful tool to overcome these challenges. It predicts the factors such as filling pressure, velocity, cooling rate, hot spots, and inside porosity. This article describes the design, simulation, experimental results, and design improvements for the complex geometries in the sand casting process. Impeller is selected as test case. The gating system was initially designed by using the text book mathematical relations and best practices recommendations. To study the predicted results of effected parameters, MAGMASOFT Software was used as a simulation tool. Three design modifications of mold design were studied. The effect of design including location and size of risers, gates on parameters such as filling pattern, pressure and velocity, cooling rate, solidification and defects such as air entrapment, hot spot, and porosity were studied. The predicted results were then compared with experimental data, and an excellent agreement between them was reported. The article highlighted the effectiveness of simulation to reach an optimal design of mold by passing the costly hit-and-trial conventional practice in the foundry industry and shows the effectiveness of simulations in time compression of casting pattern/development.

Lost Foam Casting Coating in Production of Cylinder Block

This paper introduces the application of EPC process to the inline-four diesel engine cylinder block production. It includes the make and assembles of foam shape mould, mould design, the choice of sand and modeling, and the design of gating system, etc.

Design and Optimization of Runner and Gating System for Magnesium Piston Casting through Numerical Simulation

As the lightest metal, magnesium is used as the basis for constructional alloys. A well-designed runner and gating system is very important to obtain a good quality die casting. Two types of runner and gating system for magnesium piston are designed and analyzed based on CAE software. The filling process, temperature distribution and quality predication are given respectively. Combined the solidification law, the distribution of the gas hole is effectively predicted and an optimized design is chosen. The research shows that trapezoidal gating system is better than point gating system for magnesium piston. Numerical simulation can be considered as the most cost-effective way in optimization of the runner and gating system.

Improving Design of Cricoid Plastic Gating System Based on Moldflow

To solve the problems such as poor ventilation and high production costs in the production of cricoid plastics, we analysis the reasons and look for solutions with Moldflow software to guide the new design and manufacturing of the mould. The poor ventilated structure is changed into a ventilation structure. A poor ventilation structure is changed to a good ventilation structure. Injection weight ratio was reduced from 35% to 15% - 20%, the gating system was improved, the molding process was optimized, ensuring product quality and save the cost, produced good economic benefits.

Effect of Casting Design to Microstructure and Mechanical Properties of 5 mm TWDI Plate

In producing thin wall ductile iron (TWDI) cooling rate must be strictly maintained to prevent carbide formation. There are many ways to control cooling rate BUT the most independent one is by casting design. By choosing this parameter major changes in equipment and raw material used in the foundry can be avoided. This paper discusses the effect of gating system design on microstructure and mechanical properties of 5 mm TWDI plate. A casting design based on vertical gating system is made to produce 1, 2, 3, 4, and 5 mm TWDI plates. Plate with 5 mm thickness becomes an interesting subject due to its position as the thickest and furthest from ingate in casting design with a new concept. There are three designs coded as T1, T2, and T3. These three designs were also used in making 1 and 3 mm TWDI plates of which the result has been published. The plate with 5 mm thickness will be used for automotive components. Casting design simulation for filling flow and solidification were conducted with Z-Cast. Result of flow simulation shows that the filling flow happens in two kinds. Result of solidification shows that T3 has the highest solidification rate. In the experiment, the moulds used were furan sand. Experiment result shows that all the designs have microstructure consisting of nodule graphite in ferrite matrix, no trace of carbide and skin effect are formed. Skin effect length is various for all designs. The highest nodularity is only 72% and nodule count shows only 700 nodules/mm2. Brinell hardness number for all design is beyond standard given by JIG G5502. As for UTS and elongation none of the designs exceed the minimal standard. Experiment results confirms simulation result. Compared to the previous result nodularity and nodule count decrease and curve trends for every result are not similar.

Optimization of Gating System Design for Die Casting of Thin Magnesium Alloy-Based Multi-Cavity LCD Housings

High-pressure die casting is the preferred process for manufacturing Mg-alloy components used for numerous applications. High-pressure die casting is suitable for mass production and has the advantage of also being suitable for accurately fashioning objects of complicated shapes. One disadvantage of high-speed die casting is the occurrence of defects such as shrinkage or air entrainment. Gating system design must be very effective in actual manufacturing facilities to avoid the occurrence of such defects. The objective of this study is to present a methodology for obtaining optimal designs of 4-cavity thin electronic component housings. The fluid behavior and amount of air entrainment caused by the overflows and air vent designs were analyzed using a computer fluid dynamics (CFD) simulator. The effectiveness of the proposed system was demonstrated through CFD simulations and experiments using an actual manufacturing process. Also, the effect of vacuum systems on the porosity and mechanical properties of the castings was studied. The volume of porosity in the casting was found to be significantly reduced using vacuum assistance during die casting. As a result, the tensile strength and the elongation of the die casting products are improved.

Numerical Simulation and Balance Design of Rubber Injection Mold Gating System Based on POLYFLOW

Rubber injection molding is applied in more and more applications in rubber production process. Design of gating system is the most important in rubber injection mold design. Poor runner design will lead to uneven injection velocity and pressure which affect the size and shape and the quality of the rubber products. This paper first adopted POLYFLOW numerical simulation. Three different inlet flow rates for multi-cavity mold were simulated and analyzed by POLYFLOW software in this paper. Non-equilibrium gating system was further optimized by the calculation method of Balanced Gate Value and numerical simulation. The best inlet flow rate and the best runner size were ultimately obtained. It was proven that Numerical simulation results are of great significance for rubber injection mold design and injection molding processing parameter selection.

Effect of Casting Design to Microstructure and Mechanical Properties of 3 Mm TWDI Plate

The problem occurs in producing thin wall ductile iron (TWDI) is high cooling rate due to its thickness. Cooling rate must be strictly maintained to prevent carbide formation. There are many ways to control cooling rate. Casting design is one of these, especially gating system design. This parameter is often chosen because of its independence. Major changes in equipment and raw material used in the foundry are not needed when a casting design is chosen to deal with cooling rate. This paper discusses the effect of gating system design on microstructure and mechanical properties of 3 mm TWDI plate. A casting design based on gating system design is made to produce 1, 2, 3, 4, and 5 mm TWDI plates. There are three designs coded as T1, T2, and T3. These three designs were also used in making 1 mm TWDI plates of which the result has been published. The plate with thickness of 3 mm will be used for automotive component like the crankshaft made by Martinez. The moulds used were furan sand. Beside the experiment, casting design simulation with Z-Cast was also conducted to see the behaviour of solidification in 3 mm TWDI plate. Simulation result showed every design has its own solidification behaviour for 3 mm TWDI plate, especially for T2. Experiment result showed that all the designs have microstructure consisting of nodule graphite in ferrite matrix, no trace of carbide and skin effect are formed. Skin effect length is various for all designs. Nodularity exceeded 75% and nodule count exceeded 900 nodules/mm2. Brinell hardness number for all design is beyond standard given by JIG G5502. As for UTS and elongation none of the designs exceed the minimal standard. Experiment results confirmed simulation result. Compared to the previous result nodularity and nodule count decrease and curve trends for every result are not the same.

The Computer Solidification Simulation and Process Optimization of Gear Ring

The numerical solidification simulation for gear ring steel casting has been made, and the location and reasons forming casting defects have been predicted by HUAZHU CAE software. Simulating result shows that the directional solidification and efficient feeding were maintained and the casting perfects can be realized by means of the computer simulation optimizing technological and rationally design of gating system, insulated risers, iron chill and compensating efficiently. After magnetic particle detection and ultrasonic inspection, the properties and microstructure of the Gear ring steel casting are in accord with the international standard.

Effect of Casting Design to Microstructure and Mechanical Properties of 1 mm TWDI Plate

In producing thin wall ductile iron (TWDI) cooling rate must be strictly maintaned to prevent carbide formation. There are many ways to control cooling rate and one of these is through casting design, especially gating system design. This paper discusses the possibility to produce 1 mm TWDI plate and also to note the effect of gating system design to microstructure and mechanical properties. Casting design based on gating system design are made to produce 1 mm TWDI plate. The 1 mm TWDI plates will be used for fin. There are three design and coded as T1, T2, and T3. The moulds used were made from furan sand. Beside the experiment, casting design simulation with Z-Cast was also conducted to ensure the completion of producing 1 mm TWDI plate. Simulation result showed that all designs could produce 1 mm TWDI plate. Result from experiment showed that all the designs have microstructure consisting of nodule graphite in ferrite matrix and carbide. Apart from mentioned microstructure there is also skin effect. The difference between all designs lies in carbide content and skin effect width. All the nodularity exceeded 80% and nodule count exceeded 1000 nodule/mm2. Brinell hardness number for all design exceeded minimal standard given by JIG G5502. As for UTS only T2 design can exceed the minimal standard. There is a contradictive result between experiment and simulation in cooling rate.

Experimental study of vortex flow induced by a vortex well in sand casting

Fluid flow phenomena are very closely related to the casting quality and surface finish of the cast part. In addition, the good quality of the casting product can be achieved by using an optimum gating system design. In this work, a vortex well, which is one of the important components of gating system design, is utilized in order to demonstrate its effectiveness in improving the mechanical and microstructure properties of the cast part. An X-ray radiography test was performed in order to investigate the porosity distribution in castings with different vortex well dimensions. The scatter of flexure strength results was quantified by Weibull statistics. Microstructure analysis was conducted by using a scanning electron microscope (SEM) to examine the microstructure of selected casting specimens produced from the vortex well design. By optimizing the vortex well design, porosity inside the casting was significantly reduced, while the mechanical strength and reliability of aluminum casting were further enhanced.

Numerical Simulation of Casting Process for Gray Iron Butterfly Valve

During casting process design, CAD/CAE technology can play important role to avoid macroscopic irregularity, internal defect and assure casting performance. Based on the casting process analysis and gating system design, the numerical simulation of gray iron butterfly valve was done by hydrodynamic software Flow-3D to obtain its optimal process scheme. According to the simulation results including flow field, temperature field and defect distribution, the merits and faults of designed schemes were investigated and then the feasible gating system was proposed. The results showed that, compared with top or intermediate casting, when adopting bottom casting, steady flow of molten metal and reasonable temperature distribution could be achieved. And workpiece defects mainly distributed in riser. The predicted results are in good agreement with practical ones.

Optimal Design of Plastic Injection Mould Gating System

Taking the plastic injection mould of the air conditioning panel for example, through the flow simulation and analysis of the filling mould process for three gating system design programs, the paper gets each program’s filling time, temperature, shearing rate, melting wiring and air pocket, injecting pressure and the distribution map of locking strength. Through comparing and analyzing, the paper draws the relatively good design program, and finds the shaping defect that may appear ahead of time, which improves the success rate of once-testing mould so as to realize shorten mould design cycle and reduce mould manufacturing cost.

Numerical Simulation and Technology Optimization of Rear Oil Seal Bearing Die Castings Based on ProCAST

In production,the Φ105 mm hole of rear oil seal bearing die castings often appear porosity, shrinkage and other defects , resulting in the parts to scrap. The existing gating system design of rear oil seal bearing die castings was improved , and the flow and temperature field of the two programs that before and after improvement were analyzed by ProCAST software. The simulation results predicted the casting defects, and the conclusion was consistent with the production. By using the improved process optimization, the rejection rate of die castings can be reduced effectively. Die casting is a chipless forming of casting with high casting dimensional accuracy, high surface quality and high production efficiency [1,2]. Therefore, it has developed rapidly in the automotive, communications and other industries. However, due to shrinkage, porosity and other reasons, leading to high rejection rate of castings. With the emergence of commercial casting simulation software, the casting production has been developed from semi empirical and semi theoretical onto theorization, quantification and controllable track[3-5]. In this paper, the casting defects of rear oil seal bearing is analyzed by using numerical simulation technology[6]. By optimizing the casting process, the casting quality is improved, and the rejection rate is reduced effectively.

Casting Design Through Multi-Objective Optimization

AbstractThe gating and riser system design plays an important role in the quality and cost of a metal casting. Due to the lack of fixed theoretical procedures to follow, the design process is carried out on a trial-and-error basis. The casting design optimization problem is characterized by multiple design variables, conflicting objectives and a complex search space, making it unsuitable for sensitivity-based optimization. In this study, a formal optimization method using Multi-Objective Evolutionary Algorithm (MOEA) was developed to overcome such complexities. A framework for integrating the optimization procedure with numerical simulation for the design evaluation is presented. The proposed optimization framework applied to the gating and riser system of a sand casting gave good results and provided more flexibility in decision making.