The Effect of Gating System on Quality of Traditional Rural Metal Castings of India

Melt flow and casting solidification are essential parts of the permanent mold casting process and affect significantly the quality of castings．For this reason, accurate prediction of mold filling pattern and temperature field in permanent mold castings plays on an important role in producing sound castings. In this paper, the model filling and solidification of a box casting produced from an aluminum alloy is studied. Different casting processes are employed, simulated and optimized to obtain sound castings. Simulation results reveal that with appropriate gating system, pouring rate, cooling line, a smooth mold filling, reduced shrinkages and other defects are available and desired sound castings can be produced.

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Influence of Casting Process for Technological Yield of Thin Wall Steel Castings by Last Solidifying Feeding Mechanism

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.1134 ◽

2012 ◽

Vol 538-541 ◽

pp. 1134-1137

Author(s):

Da Chun Yang

Keyword(s):

Mechanical Properties ◽

Complex Structure ◽

Casting Process ◽

Thin Wall ◽

Gating System ◽

Pouring Temperature ◽

Process Yield ◽

Feeding Mechanism ◽

Steel Castings

For the steel castings which is thin wall, uniform thickness, complex structure, and no special mechanical properties, it is feasible that the foundry technology was designed according to the last solidifying feeding mechanism. Adopting this process for the thin wall steel castings, the pouring temperature must be controlled and the gating system be designed rationally. Using self-feeding shrinkage in solidification, and the casting was poured and congealing at the same time. The shrinkage of finally congealing part was fed by small riser or gating system (no riser). Using this foundry technology, the casting process yield and surface quality of casting may be improved, the production cost is reduced, and the requirements of mechanical properties can be met.

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The Impact of the Melting and Pouring Process on the Quality of the Biggest Rocking Bell Called Vox Patris

Quality Production Improvement - QPI ◽

10.2478/cqpi-2019-0031 ◽

2019 ◽

Vol 1 (1) ◽

pp. 230-237

Author(s):

Dariusz Bartocha ◽

Czesław Baron

Keyword(s):

Liquid Metal ◽

Computer Simulations ◽

Final Stage ◽

Gating System ◽

System Parameters ◽

University Of Technology ◽

Filling System ◽

Alloy Properties ◽

The Impact

Abstract The paper describes the process of melting, metalworking and pouring the form of the world's largest 55-ton rocking bell called Vox Patris. The project was carried out by Pracownia Ludwisarska of Jan Felczyński from Przemyśl in cooperation with Rduch Bells & Clocks from Czernica and Metalodlew SA from Kraków. Comprehensive scientific and technical support of the project was provided by the Department of Foundry of the Silesian University of Technology. The bell is made of bronze, which is an alloy of copper and tin with a content of tin at the level of 20%. The foundry, where the melting and pouring process took place, had two 14 ton electric furnaces, 15 ton transport pouring ladle and a 60 ton collection ladle. Therefore, it was necessary to determine the minimum temperature of the pouring and the conditions for holding the liquid metal so that the metal from the first cast would not solidify before accumulating its total amount (four melts) (Bartocha and Baron, 2015; Bartocha and Baron, 2016). The study presents the tests of alloy properties and a series of computer simulations. Thanks to them the maximum and minimum permissible temperature of metal overheating has been determined (Bartocha, 2017). The final stage of the cast was the mold pouring process. The filling system was responsible for the correct performance of this process. This system comprised a tank (collector) under a doublestopper 60-ton main ladle, an eleven-meter tapping spout, an infusion tank and a downgate. The task of the gating system is uniform and continuous supply of liquid metal to the mold until it is completely filled. The unusual layout, that was used, required checking many factors. Various configurations of the system parameters have been tested based on the series of computer simulations (Czochlarski and Bukowski, 1935; Ignaszak, 1999).

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Computer-aided engineering (CAE) simulation for the robust gating system design: Improved process for investment casting defects of 316L stainless steel valve housing

10.21203/rs.3.rs-295542/v1 ◽

2021 ◽

Author(s):

Ming-Hsiu Ho ◽

Yi Chen Kao ◽

Cheng-Fu Huang ◽

Sheng-Chan Lee ◽

Chien-Wei Chan ◽

...

Keyword(s):

Investment Casting ◽

Shrinkage Porosity ◽

Hole Drilling ◽

Gating System ◽

Case Scenario ◽

Material Usage ◽

Retained Melt Modulus ◽

Near Net Shape ◽

Valve Housing

Abstract Defects in investment casting will inevitably reduce the lifetime and degrade the casting quality and increase manufacturing costs, accordingly. In particular, shrinkage porosity was numerically conducted, and a retained melt modulus model was implemented to analyze highly probable regions. The proposed casting schemes of gating designs are compared by 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 the near net shape casting with minimum machining cost and increase material usage. Virtual thermo-dynamical sensors were adopted in the simulations to indicate the impacts of different gating system of pattern assembly on the cooling gradient and direction of solidification. The best-case scenario of investment casting conditions was chosen to fabricate valve housing in an investment casting foundry. Experimental results of X-ray image differentiated nearly none of the pernicious defects that typically occurred with proposed casting, authenticating the proposed scheme's efficacy accordingly.

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Numerical Simulation and Evaluation of Campbell Running and Gating Systems

Metals ◽

10.3390/met10010068 ◽

2020 ◽

Vol 10 (1) ◽

pp. 68

Author(s):

Michail Papanikolaou ◽

Emanuele Pagone ◽

Mark Jolly ◽

Konstantinos Salonitis

Keyword(s):

Surface Defects ◽

Surface Film ◽

Air Entrainment ◽

Gating System ◽

Turbulent Entrainment ◽

Running System ◽

Computational Fluid Dynamics Cfd ◽

Simulation And Evaluation ◽

System Designs

The most common problems encountered in sand casting foundries are related to sand inclusions, air, and oxide films entrainment. These issues can be addressed to a good extent or eliminated by designing proper running systems. The design of a good running system should be based on John Campbell’s “10 casting rules”; it should hinder laminar and turbulent entrainment of the surface film on the liquid, as well as bubble entrainment. These rules have led to the establishment of a group of components such as high and low placed filters (HPF/LPF) and standard gate designs such as the trident gate (TG) and vortex gate (VG) which are incorporated in well-performing running system designs. In this study, the potential of the aforementioned running system designs to eliminate air entrainment and surface defects has been investigated via means of computational fluid dynamics (CFD) simulations. The obtained results suggest that the use of filters significantly enhances the quality of the final cast product; moreover, all of the gating system designs appear to perform better than the basic running system (BRS). Finally, the five in total running and gating system designs have been evaluated with respect to their ability to produce good quality cast products (reduced air entrainment and surface defects) and their sustainability component (runner scrap mass).

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Precision Casting of GTD222 Component with Complex Thin-Wall Structure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.904.46 ◽

2017 ◽

Vol 904 ◽

pp. 46-49

Author(s):

Guo Liang Zhu ◽

Wei Wang ◽

Rui Wang ◽

Guo Xiang Wang ◽

An Ping Dong ◽

...

Keyword(s):

Large Scale ◽

Wall Structure ◽

Potential Candidate ◽

Thin Wall ◽

Aircraft Engines ◽

Gating System ◽

Good Oxidation Resistance ◽

Precision Casting ◽

Thin Walled

GTD222 superalloy is a potential candidate for large-scale complex thin-walled castings with high temperature resistance in the next-generation aircraft engines, due to its excellent creep performance, good oxidation resistance and favorable weldability. The precision casting of GTD222 with a complex thin-wall structure was investigated in this work. The good quality of the final cast indicated that the optimized gating system obtained by numerical simulation was satisfying.

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Gating Systems for Sizeable Castings from Al Alloys Cast into Ceramic Moulds

Archives of Foundry Engineering ◽

10.2478/v10266-012-0038-5 ◽

2012 ◽

Vol 12 (2) ◽

pp. 65-68

Author(s):

I. Stachovec ◽

M. Horáček ◽

L. Zemčík ◽

V. Kolda ◽

J. Horenský

Keyword(s):

Al Alloys ◽

Simulation Software ◽

Aircraft Industry ◽

Ceramic Shell ◽

Trial And Error ◽

Gating System ◽

Casting Technology ◽

Trial And Error Method ◽

Error Method

Gating Systems for Sizeable Castings from Al Alloys Cast into Ceramic Moulds In contrast to casting to conventional non-reusable "sand" moulds, for which calculating technique for an optimum design of the gating system is comparatively well-developed, a trial-and-error method is applied mostly for casting to ceramic shell moulds made by the investment casting technology. A technologist selects from gating systems of several types (that are standardized by the foundry mostly) on the basis of experience. However, this approach is not sustainable with ever growing demands on quality of castings and also the economy of their fabrication as well as with new types of complex sizeable castings introduced to the production gradually (by new customers from the aircraft industry above all) any more. The simulation software may be used as a possible tool for making the process of optimising gating systems more effective.

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Application of Diffraction and X-Ray Microanalysis in Study of MMC Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.368 ◽

2013 ◽

Vol 690-693 ◽

pp. 368-373

Author(s):

Katarzyna Gawdzińska

Keyword(s):

Metal Matrix ◽

Qualitative Description ◽

Ex Situ ◽

Matrix Composites ◽

X Ray ◽

Case Identification ◽

Chemical Constitution ◽

Research Procedure ◽

Metal Castings

Quality of metal-matrix composite castings, similarly as quality of conventional metal castings is defined by the collection of data concerning chemical constitution, properties (e.g. strength) and structure of final products. During study aimed at determining these parameters, the priority is to maintain the highest possible repeatability and automation of measurement. In case of chemical constitution or mechanical properties analysis it is considerably easy to achieve thanks to application of appropriate research procedure. Analysis of structure of studied materials is however a much bigger problem. To improve it, different tools of digital image analysis are being used, but because of only slight differences (e.g. in color) between different elements of structure, conducting such analysis without performing additional study may result in obtaining false results. In such case, identification of an object is very important: unequivocal conclusion whether a given object is a reinforcement or maybe an impurity or an inclusion foreign matter, or is it a structure of improper, unintentional chemical constitution. It is particularly important concerning composites for which on the images obtained using both optical and scanning microscopy individual phases (reinforcement, matrix and impurities) are difficult to distinguish. In such case identification of particular phases is aimed at avoiding mistakes, for example while analyzing the quantity or uniformity of spacing of reinforcement phase in given space. X-ray diffraction may be a solution for this problem. An example of identification (quantitative and qualitative description) of reinforcement phase in suspension composites is presented further in the paper. The authors present also a chemical constitution of selected elements of structure of metal-matrix composites from ex-situ group.

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