Gating System Design Research Articles

Automated optimization of gating system through numerical simulation

Casting is a process for the production of complex shapes. Defects are unavoidable in any casting process. An efficient method of eliminating such defects can improve the process capability of the casting system. Computer simulation can save time, resources, and money in foundry trials, but it necessitates more human effort in terms of preparing the inputs and appropriately interpreting the results. In this work, a new method for evaluating and optimizing gating system design utilizing a simulation tool is proposed. It is possible to automatically modify the gating design with the help of CAD and casting simulation software from a given initial design and boundary conditions, and to check whether the design is effective to eliminate defects. Further this takes less human effort, making it more useful for industrial applications. The suggested methodology is demonstrated by autonomously optimizing the gating system for two industrial components and validated by producing actual castings made in sand molds.

Optimization of Multi-Gate System in Casting Process Based on Experimental Study

Abstract: This paper proposes a gating system design for casting process using an experimental study. The principle behind multi-gate system optimization is to eliminate defects such as compression gas inclusions, cold shorts and mixing etc. Industrial and research experience shows that the flow of molten metal in the gating system before entering the extraction cavity significantly influences the quality of the casting. In general, slow filling causes defects like cold shirt and mixing while fast filling causes inclusion of sand and causes defects like holes. A gating system consists of runners, sprue gates and filters. The position, number, size, and shape of these elements play an important role. A systematic methodology for gating design optimization considering filling rate maximization has been developed based on limiting constraints. These include pouring time, gating ratio, modulus of ingate, mold erosion, Reynolds number at ingate section and filling rate of molten metal. Molten metal kinematics viscosity similar to that of liquid water can be used to determine the fillings and flowrate of the molten metal in the mold cavity. Aluminum generally has the same kinematics as water. Thus the water flow can be studied by adding the necessary design improvements to the multi-gate system, from which it will be easier to detect defects and will be easier to detect defects and will greatly improve the overall casting quality

Effect of Gating System Design on the Quality of Aluminum Alloy Castings

In this paper, a naturally pressurized gating system has been designed to reduce the turbulence of the melt during casting. The influence of gate dimensions, foam filters, a trident gate and a vortex element were evaluated. Their effect on melt velocity, flow characteristics, number of oxides, casting properties and mechanical properties were observed. ProCAST Simulation software v.2023 and a water flow test were also evaluated to assist in the experimental evaluation of the castings. Melts showed a relationship between melt velocity and porosity of castings. Quantitative evaluation of the surface porosity showed a trend of decreasing porosity with decreasing melt velocity. The greatest reduction in the melt velocity was achieved by a M4 design, which was associated with the highest reduction in the oxides. The pores analyzed proved the presence of oxide layers on their inner surface and a possible theory of pore formation when the initiator of porosity is entrained double oxide layers. The best metal yield was achieved with M1, but the difference between M2 and M4 was negligible (2–5% yield difference), so it can be stated that the beneficial effect of the M4 design in providing the best quality castings is not negated by the increase in metal yield.

Design of gating systems for combined mould casting of thin-walled body products made of light alloys

The basis of calculation procedure for design of gating systems are considered. These methods provide filling with a melt from light alloys of metal mould with sand rods, which form the internal surfaces of thin-walled and stretched walls of body castings. Approval of the developed program based on the presented calculation procedure is carried out using CSoft Development "PoligonSoft".

Design and optimization of runner and gating systems, in high-pressure casting and sand casting, for an aluminum alloy valve cover

The weight and speed advantage of aluminum die-casting leads to its use in many parts in the automotive industry. Casting simulation programs are used, to avoid time-consuming and expensive production costs, and to design the production process. For casting production one of the most important factors is the runner design, which directly affects castability, material selection, and casting quality. With the correct design of runner systems, there will be no problem with the casting part. In this study, the final part and the runner design for the aluminum alloy valve cover were modeled in CAD, according to the empirical calculations. Furthermore, an appropriate casting method was selected for the valve cover not only according to the results of both high-pressure die-casting and sand-casting simulations but also economic calculations. The main technical parameters for selection were mold and part temperature distribution, liquid metal flow rates, cold shut possibilities, final air quantities, microporosity, and microporosity values. After the final decision, the casting part was produced with high pressure die casting by the implementation of the final runner design.

Parametric Study for Runner Modifications of Die Casted Part with Venting Systems

High-pressure die casting (HPDC) is a process used for creating complex components by injecting the molten metal inside the cavity at high pressure. Failure in die casting may reduce product mechanical properties, surface quality, and life cycle. In this paper, the die-casting process of an inspection instrument – test piece is investigated for parametric study and Computational fluid dynamics (CFD) analysis. Parameters used in the die-casting process are important since it affects the molten flow quality inside the cavity. Thus, a parametric study is done to investigate the optimum parameter use in the die-casting process of the test piece. Runner gating system design is also one of the important criteria to maintain the quality of products. This paper also investigated the effect of runner gating system design optimization in reducing gas porosity. The CT scan of the sample mold is included to compare the relationships between gas porosity occurrence with CFD results. This paper proposed a new runner design named outward curvature runner with an air vent that can improve velocity and temperature distributions in reducing die-casting defects. In addition to that, air vents are installed to extend the volume and promote higher suction, to eliminate gas bubbles entrapment inside the cavity.

A multimodal data-driven design of low pressure die casting gating system for aluminum alloy cabin

The design of gating systems for large and complex thin-wall castings requires the application of empirical equations and a substantial number of iterative experiments. In this study, a novel machine learning-based design strategy is proposed for the gating system of large and complex thin-walled castings. The gating system of castings was estimated using a multi-input multi-output neural network model, which incorporated visual, textual, and numerical multimodal features. The R2 value of the model accuracy reached 0.981, and the predicted parameters for the gating system were a slot runner width of 27 mm, a slot runner length of 48 mm, a riser runner diameter of 60 mm, and the number of riser runners of 8. The EasyCast and Procast simulation software were utilized for comparison and verification, resulting in a smooth filling and the achievement of sequential solidification. Finally, the mechanism of casting defects is discussed using the solidification phase-field model of EasyPhase system, elucidating how the alloy system can serve as a distinguishing feature in machine learning models that impact gating system parameters. This strategy is anticipated to enhance the efficiency of low pressure die casting process design, thereby serving as a valuable reference for intelligent process design in low pressure die casting.

Gating system design and casting simulation application for the grooved worm wheel by using zinc alloy sand casting process

Bottom-up gated filling system was performed to produce worm wheel through a sand casting of zinc alloy. It was a symmetrical design in which two worm wheels were cast at once, the worm wheel was erected in the direction of gravity and had a gating system in which molten zinc alloy were poured from below. The recovery rate of the designed mold cavity was 60%. Casting analysis was performed to check that the worm wheel was sequentially filled without turbulent flow as the molten zinc alloy passed through the gate. Though the speed of the molten zinc alloy initially poured was unstable, it became stabilized while maintaining a constant speed due to the continuous inflow. The results of directional solidification were confirmed. An integrated mold cavity pattern was fabricated by 3D printer, and sand mold were manufactured accordingly. A sound worm wheel without defects could be fabricated through sand casting.

Optimization of The Gating Design For AA2024 Base Alloy Casting using Numerical Method

Aluminum alloys are widely used engineering materials in a various field. AA2024 alloy is one of the most used alloys in the aerospace as well as automobile industry. At the time of the casting of the alloy, casting defects like porosity, shrinkage, etc. are induced in the alloy. The casting defects can be minimized by optimizing the gating system or by changing the composition of the material. In the present study, the simulation of casting process for optimizing the gating system was done with help of numerical method. Three different gating system designs (i.e., Top Gating design, Bottom gating design and anti-gravity gating design) were simulated for the casting process and the results of the simulations were interpreted. The anti-gravity gating system design was found out to be the best design which exhibits casting with minimum defects.

Investigation of Structure and Mechanical Characteristics of a High Manganese Steel via SolidCast Simulation Method

Casting is a fabrication method used to create various industrial parts with different shapes. Flaws such as shrinkage, porosity, and short metal filling can result in casting rejection. These flaws are heavily reliant on casting parameter design (gating and riser system design) and can be reduced by optimizing the casting parameter design. The development of materials with new or improved properties has long been the primary objective of materials scientists. The designing of metallic alloys for structural purposes must take strength, toughness, and formability into account to achieve the desired performance. The unique convergence of these essential characteristics that characterize high manganese steels fascinate scientists worldwide. The current work systematically investigated a gating system and riser design effect for high Manganese steel samples (bushes) to develop an understanding of the structure–property relationship. The first conventional manual calculation was performed to design the gating and riser system. Subsequently, a sophisticated simulation software called SolidCast was used to design, validate, and improve the casting parameters of the specimen. To back up the findings, confirmatory experiments were carried out. Both designs were used to make castings in order to check for flaws. The microstructural and mechanical characteristics of these materials were investigated. Visual inspection of the manually-designed castings revealed considerable shrinkage, whereas software-designed castings seemed in good shape, without the shrinkage, macroporosity, and microporosity. The microstructure of the specimens was also studied by applying optical microscopy and SEM analysis. By improving the gating and riser system with the SolidCast software, sound casting was achieved. This improved the quality of casting results with a considerable enhancement of yield strength (~32 percent), hardness (~34 percent), and tensile strength (~27 percent), which may lead to significant cost savings.

Search procedure for optimal design and technological solutions to ensure dimensional and geometric accuracy of castings

The object of research in the work is the technology of manufacturing shaped castings in disposable sand molds. The existing problem is that the imperfection of design and technological solutions at the stage of developing the technology of a single sand mold casting leads to deviations in the dimensions and geometry of the castings after their manufacture from the requirements of technological documentation. This can lead to an irreparable shortage of casting. To develop measures to eliminate or minimize the event, which consists in the formation of a shortage of castings in terms of dimensional and geometric accuracy, a procedure for searching for optimal design and technological solutions is proposed. A hypothesis has been put forward that a significant factor that leads to deviations in the dimensional and geometric accuracy of castings from the requirements of technological documentation is the imperfection of the gating system design. It is demonstrated on specific castings how this factor can influence the formation of uneven wall thickness. The proposed procedure, which includes 10 consecutive steps, allows to build a plan for a complete factorial experiment and obtain a regression equation for it, linking the parameters of the gating system with indicators of dimensional and geometric accuracy. The presence of such equations provides the possibility of further experimental optimization and determination of design and technological solutions for the development or improvement of casting systems that minimize the deviations of the dimensional and geometric accuracy of castings from the requirements of technological documentation. This also minimizes the likelihood of an event consisting in the formation of an irreparable shortage of castings. The presented study will be useful for machine-building enterprises that have foundries in their structure, where shaped castings are made in disposable sand molds.

Rapid Prototyping and Tooling Technology to Assist the Development of Low-Cost Dies

This case study aims toward the importance of the application of rapid prototyping and tooling technology in die design and manufacturing. Many conventional machining processes of die manufacturing, including computer numeric control (CNC) machining and electric discharge machining (EDM), are used by the local manufacturers of die, but these processes are time-consuming and expensive. There is a need to explore opportunities to reduce die manufacturing costs. This paper aims to assist the development of low-cost dies through the application of rapid prototyping and tooling technology. For this purpose, solid works software was used to design the die of a 4-hole Lego Block. 3D printing was incorporated in the existing capability of investment casting process for die manufacturing. A proper gating system design consideration was taken into account to ensure the accurate flow of casting material for achieving fine surface finish. From the results, it has been observed that gating system design with four ingates gives the optimum value of surface finish (~3.4156μm). The proposed rapid prototyping and tooling technology makes the practitioners (tool makers) capable of making dies with complex shapes, superior surface finishes, and dimensional accuracy in less or no time.

Redesigning and numerical simulation of gating system to reduce cold shut defect in submersible pump part castings

Gating system design is an essential element in casting that significantly affects the melt's molten metal flow behaviour, heat transfer, and solidification. Improper gating system leads to pouring-related defects like cold shut, misrun, etc. Submersible pump-bearing block castings produced in one of the leading foundries are rejected due to a cold shut defect. It was identified that the improper gating system is the probable cause for rejection. The bearing block and the existing gating system were modelled in 3D modelling software, and the molten metal flow behaviour of casting was simulated with casting simulation software. Based on the simulation results, the existing gating system was redesigned following established empirical relations. The component with the revised gating system was analysed for flow behaviour through simulation with the software. With the revised gating system, elimination of cold shut is observed, and the revised gating design is recommended to the industry for implementation. The effectiveness of the revised gating system is also validated with pump diffuser casing, which has similar geometrical and material characteristics. The simulation results and experimental validation showed a reduction in flow and surface defects. Appropriate design of the gating system and balanced arrangement of cavities in the gating system are noted to reduce the flow and surface-related defects. It is observed that with the revised gating systems, the percentage of rejection is reduced from 28.36% to 2.34% and 23.43% to 2.45% for the bearing block and pump diffuser casing respectively.

Tribological Studies of Shrinkage Defect and Effective Yield Upgrade of Grey Cast-Iron Castings

Abstract: This study aims to examine the shrinkage flaw in grey cast iron. The poor gating system design, improper composition management, and solid sections with a high modulus (Volume/ Surface area) in the casting are the root causes of the shrinkage fault. The gating mechanism can first be redesigned in order to lessen shrinkage. A new gating system with a different chemical makeup is suggested. Grey cast iron's composition changed due to an increase in carbon content. Thus, proCAST is used to develop and analyze the gating system. Implementing the planned gating system in the foundry served to validate the results. It is accomplished to increase the effective yield

Optimal Design of the Gating and Riser System for Complex Casting Using an Evolutionary Algorithm.

The gating and riser system design is essential for both quality and cost in large-scale casting and is expected to reach several objectives simultaneously. However, even with the help of commercial simulation software, the design of gating and riser systems is still the result of a long-term trial-and-error optimal process owing to the conflict between the objectives. Several evolutionary algorithms (EAs) have been reported to be helpful in the selection of the geometrical dimensions of gating and riser systems. In this study, a route with sequential use of a multi-objective EA and single-objective optimization algorithm was developed to help design gating and riser systems, respectively. This route was applied in an actual case and verified using commercial simulation software. The results showed a dramatic decrease in the time cost in design and acceptable casting quality. Thus, the proposed design method is time-saving.

Optimization of Gating System for Sand Casting Using Sequential Quadratic Programming

Abstract: Lower rate of filling of metal in sand casting is a common and avoidable problem in the production unit. This often leads to increase in expenses as well as time taken. By optimizing the gating system design, we can reduce the inferiority in the products and hence reduce the cost and time taken

Failure analysis of a clutch wheel for wind turbines with the use of casting process simulation

Production of high-quality and high-grade casts at the lowest possible cost is a priority of every foundry. Innovation and optimization of the currently applied production processes is a necessary step to achieving such a goal. Costly and long experiments performed in real foundries may be replaced with numerical simulations, as they provide reliable representation of the casting process using the computer technology. A detailed analysis of simulation results facilitates forecasting various risks that might negatively affect the quality of produced casts, and hence the quality of the entire production process. The present article discusses the effects of adjustments to the design of a gating system on the quality of a cast made of EN-GJS-500-7 ductile cast iron, which is used as a clutch wheel in turbines in wind power plants. During the production of the cast, two models of the gating system were created in Solid Works CAD software. The gating systems were validated using NovaFlow&Solid casting simulation software. The modification of the gating system design resulted in a reduced amount of liquid metal used for casting, which has significant economic effects in the mass production. Eight simulations of the designed gating systems were carried out. The main purpose of the simulations was to determine the mesh density as well as the casting and solidification conditions so that they are as close as possible to the real conditions in a foundry. Subsequently, the gating system was modified with the result of eliminating defects in the cast that occur during the solidification process as well as increasing the utilization of liquid metal.

Computer-Aided Engineering (CAE) Simulation for the Robust Gating System Design: Improved Process for Investment Casting Defects of 316L Stainless Steel Valve Housing

Defects in investment casting will inevitably reduce the lifetime, degrade the quality of the casting, and increase the manufacturing costs. In this paper, the potential for shrinkage porosity was numerically determined and a retained melt modulus (RMM) model was implemented to analyze highly probable regions. The proposed casting schemes of gating designs are compared by the quality of casting (shrinkage porosity) and practical feasibility in terms of small hole drilling machinability. The purpose of this study was to determine the feasible plan with the lowest PES (percentage of elements with shrinkage porosity) while promoting near-net shape casting with minimum machining cost and increasing material usage. Virtual thermo-dynamical sensors (VTDSs) were adopted in the simulations to indicate the impacts of different pattern assembly gating systems on the cooling gradient and direction of solidification. VTDSs were used in simulating and virtually monitoring the casting systems, with the aim of characterizing the rates and directions of solidification in various regions of the cast. The best-case scenario of investment casting conditions was chosen to fabricate valve housing in an investment casting foundry. The experimental results of the X-ray image differentiated nearly none of the pernicious defects that typically occurred with the proposed casting, confirming the efficacy of the proposed scheme accordingly.

Reliability and properties enhancement of as-cast aluminum alloy through gating system design

In this work, the influence of temperature on fluidity and gating system design on the physical, and mechanical properties of as-cast AA6063-T6 aluminum alloy have been examined. The pouring temperature has been used as a controlling parameter for flowability measurement and a spiral ceramic placed in a sand mold for measuring the fluidity index of the molten alloy. A linear relationship between the casting temperature and the fluidity length was observed. These show that fluidity increases linearly with the pouring temperature. Also, an expanding systems and pressurized gating systems were experimented through sprue-runner to cross-sectional area variation. The ultimate tensile strength of the samples was not significantly affected by the in-gate system design. Meanwhile, the fracture elongation seemed to be more dependent on the melt quality than on the in-gate system design. The true stress-strain graph indicates that expanding systems are better than pressurized systems. The plot of residual against fit for regression analysis does not show random distribution about the reference point.

Design of gating system for propeller casting through melt flow simulation

Design of gating system for propeller casting through melt flow simulation