Geometry Dependency of Filling Related Defects

Geometry Dependency of Filling Related Defects

  ijett-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2013 by IJETT Journal
Volume-4 Issue-5                      
Year of Publication : 2013
Authors : Tejas Prajapati , Mayur Sutaria

Citation 

Tejas Prajapati , Mayur Sutaria. "Geometry Dependency of Filling Related Defects". International Journal of Engineering Trends and Technology (IJETT). V4(5):1320-1324 May 2013. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group.

Abstract

During mould filling in casting process, defects such as mis run, cold shut, gas and oxide film entrapment and shrinkage often occur. The development of filling related defects are mainly governed by metal fillability. In practice, these defects are eliminated by iteratively designing casting filling ( gating ) system through experience and experim ents, but it requires large number of shop floor trials; taking huge amount of resources (cost) and time. This can be avoided by conducting trials on computer using casting simulation technology. Three varying thickness parts with different shape complexity have been designed to quantify the mould filling characteristic . Part shape complexity depends on geometry parameters such as volume and surface area of part, volume of thin section, section thickness , number of cored features, core volume etc. Mould filling and solidification analysis of these parts have been carried out using ANSYS. The information derived from the simulation is used to quantify the metal fillability index. A linear correlation has been found between shape complexity and mould fillability index. It is observed that more complex part has poor fillability index (and thus, poor manufacturability) as compared with less complex parts.

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Keywords
casting simulation, casting defects, coldshut, misrun , shape complexity, fillability .