IJBTT

Effects of Improved Gating System by Using Standard Gating Ratio

	International Journal of Engineering Trends and Technology (IJETT)
	© 2015 by IJETT Journal
	Volume-22 Number-4
	Year of Publication : 2015
	Authors : Shashank V. Gulhane, A. D. Shirbhate
	DOI :  10.14445/22315381/IJETT-V22P237

Citation 

Shashank V. Gulhane, A. D. Shirbhate"Effects of Improved Gating System by Using Standard Gating Ratio", International Journal of Engineering Trends and Technology (IJETT), V22(4),174-177 April 2015. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
One of the key elements to make a metal casting of high quality is the design of a good gating system. The gating system refers to those channels through which the metal flows from the ladle to the mold cavity. The use of a good gating system is even more important if a casting is produced by a gravity process. If poor gating techniques are used, invariably, lower casting quality is achieved, because of damage on the molten metal received during the flow through the gating system. It could be even worse, if the molten material is a sensitive metal for receiving damage during the filling, because of dross and slag formation. The purpose of this study is to identify the problem associated with gating system for the manufacturing of ginning dead weight which is used for their machineries at Jadhao Steel Alloys, Amravati . The typical casting defects were identified at M/s Jadhao Steel Alloys, Amravati in which the shrinkage defect ,blow holes, pin holes, gas holes, sand inclusion and misrun defects etc. are prominent. The total percentage of defect is around 25-30 % of the total casting produced. It means total % of rejection is around 25-30% which is very high and not acceptable. After careful investigation of the casting process, it was found that all the above defects can be considerably reduced by using a proper gating system. Hence optimization of gating system is considered as a main topic of investigation. According to deep study and analysis of existing gating system used by industry, it was found that old gating ratio was incorrect and after gating system calculations it was found that the total of weight of gating system is very high that has to reduce considerably. After careful observation and analysis of existing gating system used by industry, it was decided to make necessary changes in the design and dimension of gating system. By using proposed gating system the experiment has been carried out at Jadhao Steel Alloys, Amravati. The result found after experimentation are very sound and productive. By using standard gating ratio as per ISO, it was found that the total percentage of productivity improved from 42% to 74% by reducing total weight of gating system from 4.68 kg to 2.39 kg with reducing total percentage of rejection from 25% - 30% to 7.5% - 10%, With % of yield increases from 86% to 92%, with keeping flow laminar through all sections of gating system which is most essential to reduce casting defects.

 References

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Keywords
Gating Ratio, Gating System, Jadhav Steel Alloys, Casting Defects, Productivity.