The Reynolds number of molten metal flowing mold cavity causes bulk turbulence and is the main cause of defects like shrinkage porosity and sand erosion.Machined housings with shrinkage porosity at critical bearing bo...The Reynolds number of molten metal flowing mold cavity causes bulk turbulence and is the main cause of defects like shrinkage porosity and sand erosion.Machined housings with shrinkage porosity at critical bearing bores and surface made the casting useless.In old gating casting areas of perimeters 290mm and 264mm of transmission housing,Reynolds numbers were observed as 16307 and 13806,respectively using simulation software.Data were collected from experiments to change casting area perimeters from 785mm and 785mm along with the addition of overlap area.New Reynolds numbers at two locations were observed as 3705 and 3393,respectively.Molten metal pressure,velocity and temperature results were related for final shrinkage results of the components on full production.The purpose of the study is to reduce shrinkage and porosity defects in green sand casting part using MAGMAS simulation software.High outcome was the reduction of casting machining rejection in transmission housing casting from 5.8%0.7%with savings of approximately 0.13 million USD over the period of 14 months.Implications of this work include casting defects study and reduction in different grades and weight range.展开更多
The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inocula...The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.展开更多
文摘The Reynolds number of molten metal flowing mold cavity causes bulk turbulence and is the main cause of defects like shrinkage porosity and sand erosion.Machined housings with shrinkage porosity at critical bearing bores and surface made the casting useless.In old gating casting areas of perimeters 290mm and 264mm of transmission housing,Reynolds numbers were observed as 16307 and 13806,respectively using simulation software.Data were collected from experiments to change casting area perimeters from 785mm and 785mm along with the addition of overlap area.New Reynolds numbers at two locations were observed as 3705 and 3393,respectively.Molten metal pressure,velocity and temperature results were related for final shrinkage results of the components on full production.The purpose of the study is to reduce shrinkage and porosity defects in green sand casting part using MAGMAS simulation software.High outcome was the reduction of casting machining rejection in transmission housing casting from 5.8%0.7%with savings of approximately 0.13 million USD over the period of 14 months.Implications of this work include casting defects study and reduction in different grades and weight range.
基金The paper was financially supported by the National Natural Science Foundation of China(Grant No.59235102).
文摘The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.
