英制螺纹 对应公制( mm) 底孔直径 公制螺纹 底孔直径
1/8" 3.18 2.70 M1.0 0.80
5/32" 3.97 3.30 M2.0 1.80
3/16" 4.76 3.80 M3.0 2.50
1/4" 6.35 5.10 M4.0 3.30
5/16" 7.94 6.60 M5.0 4.20
3/8" 9.53 8.00 M6.0 5.00
7/16" 11.11 9.40 M7.0 6.00
1/2" 12.70 10.70 M8.0 6.80
5/8" 15.88 13.70 M9.0 7.80
3/4" 19.05 16.70 M10.0 8.50
7/8" 22.23 19.50 M12.0 10.30
1" 25.40 22.40 M14.0 12.00
M16.0 14.00
M18.0 15.50
M20.0 17.50
M22.0 19.50
M24.