模样放大率与模样负数

Pattern Magnification and Pattern Allowance

模样放大率是指根据铸件图纸制作模样时 ,模样相对铸件图纸放大的百分数 ,其值为模样尺寸与铸件图纸尺寸之差除以铸件图纸尺寸的百分数。模样负数是指为抵消铸件凝固过程中 ,因石墨化膨胀而使铸件外凸变形 ,在模样上相应减去的尺寸。

The pattern magnification is the ratio which can be obtained from a size difference between the patter size and the blue printing size divided by the original size of the blue print. Pattern allowance is the size which is deduced from the pattern.