The Relation between Riser Design and Liquid, Solidification Contraction of Flake and Spheroidal Graphite Cast Iron

• Main Authors: Tai-yuan Ho, 何泰元
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/99559367250736788185

碩士 === 逢甲大學 === 機械工程學所 === 98 === This research is based on the results of liquid & solidification contraction for different grade flake(FC150, FC250, FC350) & spheroidal(FCD450-10, FCD600-3, FCD800-2) graphite cast iron obtained from the previous researchs. The objective of this research is to investigate the effects of riser design (riser type, riser size, and neck) on the improvement of liquid & solidification contractions of the flake & spheroidal graphite cast iron in order to obtain a sound casting with good quality. The results of this study indicate in three ways： A. In riser size design： (1)In top riser size design：The order of optimum top riser size for flake graphite cast iron (FC150, FC250, FC350) is 0.875X, 1.125X, 1.3X (X=casting thickness=60mm)；The order of optimum top riser size for spheroidal graphite cast iron(FCD450-10, FCD600-3, FCD800-2) is 0.75X, 1.0X, 1.5X (X=casting thickness=60mm). (2)In side riser size design：The optimum side riser size for flake graphite cast iron(FC250) is 1.5X (X=casting thickness=60mm)；The optimum side riser size for spheroidal graphite cast iron(FCD600-3) is 1.125X (X=casting thickness=60mm).As the liquid & solidification contraction increases, the top & side riser size must be increased. Furthermore, The effective of contraction compensation for top riser is better than that for side riser. B. In neck cross section area design： (1)The order of optimum top & side neck cross section design for flake graphite cast iron(FC250) is 0.3Y, 0.2Y (Y=riser diameter, 67.5mm, 90mm respectively).(2)Both of optimum top & side neck cross section design for spheroidal graphite cast iron(FCD600-3) are 0.4Y (Y=riser diameter, 60mm, 67.5mm respectively). In summary, the minimum value of neck diameter riser design for flake graphite cast iron (FC250) is 0.3Y (Y = riser diameter = 67.5mm);And the minimum value of neck diameter riser design for spheroidal graphite cast iron(FCD600-3) is 0.4Y (Y = riser diameter=90mm). C. In neck length design： (1)The order of maximum top & side neck length for flake graphite cast iron (FC250) is 0.6Z, 2.8Z (Z=casting thickness, =60mm). (2) The order of maximum top & side neck length for spheroidal graphite cast iron(FCD600-3) is 1.2Z, 3.4Z (Z=casting thickness=60mm). As the liquid & solidification contraction increases, the top & side neck allowed length must be shortened. Furthermore, The maximum neck length for side riser is longer than top riser.