螺纹孔冲孔翻边预加工孔径 DIN 7952 Blatt 2 Sheet matal anchorage with threads;proposed dimensions for pre-cuted hole 尺寸为 mm 表中值为指导推荐值( 见说明) 普通螺纹 M2至 M10 s h/s 预加工孔径 d 4 螺纹 M2 M3 M4 M5 M6 M8 M10 2 2 2xx 1 xx 2xx 2 x 2xx 3 3 2x 2 2x 4 2x 3 ...