Basic requirements for dimensioning 标注尺寸的基本要求 3.Dimension construction尺寸的组成 28 -1b 约46 18 44 -2~3mm Orientation of linear dimensions 1 Dimension text should be marked above or left the dimension line. All linear dimensions should be marked heading upwards for horizontal Dimension dimensions,heading towards the left for vertical dimensions. text 线性尺寸数字注在尺寸线上方或左方，字头向上或左，垂直尺寸线。 尺寸数字 2 Dimension text can also be entered in the breaking space of the dimension line. 尺寸数字不得被图线穿过，应中断图线或将其引出填写。 3 When there is 30for horizontal line,dimension text can also be placed somewhere else using a leader line. 尽量避免在与垂直方向成30°范围注尺寸，当无法避免时，可引出注 请点击鼠标左键显示后面的察 eWP国山4 38 3. Φ18 7 23mm 1b 约 4b 44 28 44 30 Extension line 1 24 8 9999 99 9 Dimension text Φ18 38 22 Orientation of linear dimensions