1、常用螺纹尺寸对照表英制螺纹 中国标准管螺纹 公制螺纹粗牙(UNC) 细牙(UNF) 螺纹尺寸 大径(mm) 小径(mm) 粗牙 细牙螺纹尺寸 底孔(mm)底孔 螺纹尺寸 底孔(mm)底孔 G1/8“-28 9.73 8.5 螺纹尺寸 底孔(mm) 螺纹尺寸 底孔(mm)3#-48 2.0 .0785“ 3#-56 2.05 .081“ G1/4“-19 13.2 11.4 M2.5*0.45 2.1 M2.5*0.35 2.124#-40 2.26 .089“ 4#-48 2.4 .935“ G3/8“-19 16.7 15.0 M3*0.5 2.5 M3*0.35 2.625#-40 2.6
2、 .1015“ 5#-44 2.65 .104“ G1/2“-14 21.0 18.6 M4*0.7 3.3 M4*0.5 3.466#-32 2.7 .1065“ 6#-40 2.87 .113“ G3/4“-14 26.4 24.1 M5*0.8 4.2 M5*0.5 4.468#-32 3.45 .136“ 8#-36 3.45 .136“ G1“-11 33.3 30.3 M6*1 5.0 M6*0.75 5.210#-24 3.7 .147“ 10#-32 4.0 .159“ G1-1/4“-11 42.0 39.0 M8*1.25 6.7 M8*0.75 7.212#-24 4.5
3、 .177“ 12#-28 4.6 .180“ G1/1/2“-11 47.8 44.9 M10*1.5 8.4 M10*1 8.91/4“-20 5.1 .201“ 1/4“-28 5.4 .213“ G2“-11 59.6 56.7 M12*1.75 10.2 M12*1 10.95/16“-18 6.5 .257“ 5/16“-24 6.9 .272“ 美国标准管螺纹(NPT) M14*2 11.9 M14*1.5 12.43/8“-16 7.94 5/16“ 3/8“-24 8.4 .332“ G1/8“-27 10.0 8.4 M16*2 13.9 M16*1.5 14.47/16“
4、-14 9.35 .368“ 7/16“-20 9.9 25/64“ G1/4“-18 13.2 11.1 M18*2.5 15.3 M18*1.5 16.41/2“-13 10.7 27/64“ 1/2“-20 11.5 29/64“ G3/8“-18 16.7 14.3 M20*2.5 17.3 M20*1.5 16.49/16“-12 12.3 31/64“ 9/16“-18 13.1 33/64“ G1/2“-14 21.3 17.86 M24*3 20.8 M24*1.5 22.45/8“-11 13.5 17/32“ 5/8“-18 14.7 37/64“ G3/4“-14 26.
5、6 23.0 M27*3 23.8 M27*1.5 25.43/4“-10 16.7 21/32“ 3/4“-16 17.5 11/16“ G1“-11.5 33.4 29.0 M30*3.5 26.3 M30*1.5 28.47/8“-9 19.5 49/64“ 7/8“-14 20.6 13/16“ G1-1/4“-11.5 42.1 37.7 M36*4 31.7 M36*1.5 34.41“-8 22.2 7/8“ 1“-12 23.4 59/64“ G1/1/2“-11.5 48.2 43.66 M42*4.5 37.2 M42*1.5 40.41-1/4“-7 28.2 1-7/64“1-1/4“-12 29.8 1-11/64“ G2“-11.5 60.3 55.56 M48*5 42.6 M48*2 45.8
