螺纹基本尺寸对照表要点

英制管螺纹基本尺寸及公差（牙形角 55º）BSPPBSPP 基本直径 螺纹代号 内螺纹 A 级 大径中径小径中径公差小径公差 中径公差 0 -0.107 -0.125 0 -0.125 0 -0.142 0 -0.142 0 -0.142 0 -0.180 0 -0.180 0 -0.180 0 -0.180 0 -0.217 0 -0.217 0 -0.217 大径公差 0 -0.214 -0.250 0 -0.250 0 -0.284 0 -0.284 0 -0.284 0 -0.360 0 -0.360 0 -0.360 0 -0.360 0 -0.434 0 -0.434 0 -0.434 外螺纹 B 级 中径公差 0 -0.214 -0.250 0 -0.250 0 -0.284 0 -0.284 0 -0.284 0 -0.360 0 -0.360 0 -0.360 0 -0.360 0 -0.434 0 -0.434 0 -0.434 大径公差 0 -0.214 0-0.250 0 -0.250 0 -0.284 0 -0.284 0 -0.284 0 -0.360 0 -0.360 0 -0.360 0 -0.360 0 -0.434 0 -0.434 0 -0.434 G1/8″×28 G1/4″×19 G3/8″×19 G1/2″×14 G5/8″×14 G3/4″×14 G1″×11 G1.1/4″×11 G1.1/2″×11 G2″×11 G2.1/2”X11 G3”X11 G3.1/2”X11 9.728 13.157 16.662 20.955 22.911 26.441 33.249 41.910 47.803 59.614 75.184 87.884 100.330 9.147 12.301 15.806 19.793 21.749 25.279 31.770 40.431 46.324 58.135 73.705 86.405 98.851 8.566 11.445 14.950 18.631 20.587 24.117 30.291 38.952 44.854 56.656 72.226 84.926 97.372 +0.170 +0.125 +0.125 0 +0.142 0 +0.142 0 +0.142 0 +0.180 0 +0.180 0 +0.180 0 +0.180 0 +0.217 0 +0.217 0 +0.217 0 +0.282 0 +0.445 +0.445 0 +0.541 0 +0.541 0 +0.541 0 +0.640 0 +0.640 0 +0.640 0 +0.640 0 +0.640 0 +0.640 0 +0.640 0 英制锥管螺纹基本尺寸及公差（牙形角55º）BSPTBSPT 基面上的直径 螺纹代号 R1/8″×28 R1/4″×19 R3/8″×19 R1/2″×14 R3/4″×14 R1″×11 R1.1/4″×11 R1.1/2″×11 R2″×11 R2.1/2”X11 R3”X11 大径 9.728 13.157 16.662 20.955 26.441 33.249 41.910 47.803 59.614 75.184 87.884 中径 9.147 12.301 15.806 19.793 25.279 31.770 40.431 46.324 58.135 73.705 86.405 小径 8.566 11.445 14.950 18.631 24.117 30.291 38.952 44.845 56.656 72.226 84.926 基本 4.0 6.0 6.4 8.2 9.5 10.4 12.7 12.7 15.9 17.5 20.6 基准长度 最大 4.9 7.3 7.7 10.0 11.3 12.7 15.0 15.0 18.2 21.0 24.1 最小 3.1 4.7 5.1 6.4 7.7 8.1 10.4 10.4 13.6 14.0 17.1 有效螺纹长度 基本 6.5 9.7 10.1 13.2 14.5 16.8 19.1 19.1 23.4 26.7 29.8 最大 7.4 11.0 11.4 15.0 16.3 19.1 21.4 21.4 25.7 30.2 33.3 最小 5.6 8.4 8.8 11.4 12.7 14.5 16.8 16.8 21.1 23.2 26.3 圆锥内螺纹基面轴向 位移偏差（±mm） 1.1 1.7 1.7 2.3 2.3 2.9 2.9 2.9 2.9 3.5 3.5 R3.1/2”X11100.33098.85197.37222.225.718.731.434.927.93.5 美制管螺纹基本尺寸及公差（牙形角 60º）UN(F)UN(F) 外螺纹 公差等级 螺纹代号 大径 最大最小最大 2A 中径 最小 JIC 螺纹 7/16″×20UNF 1/2″×20UNF 9/16″×18UNF 3/4″×16UNF 7/8″×14UNF 1-1/16″×12UN 1-5/16″×12UN 1-5/8″×12UN 1-7/8″×12UN 2-1/2″×12UN 9/16″×18UNF 11/16″×16UN 13/16″×16UN 1″×14UNF 1-3/16″×12UN 1-7/16″×12UN 1-11/16″×12UN 2″×12UN 5/8″×18UNF 1-1/16″×14UN 9/16″×16UN 7/8″×12UN 2-1/4″×12UN 11.079 12.667 14.252 19.012 22.184 26.944 33.294 41.229 47.579 63.452 14.252 17.427 20.599 25.357 30.119 36.467 42.817 50.754 15.839 26.947 14.252 22.182 57.104 10.874 12.461 14.031 18.773 21.923 26.655 33.005 40.94 47.29 63.162 14.031 17.188 20.361 25.095 29.83 36.177 42.527 50.465 15.618 26.683 14.013 21.892 56.815 10.254 11.841 13.335 17.981 21.006 25.57 31.92 39.885 46.205 62.078 13.335 16.396 19.568 24.178 28.745 35.093 41.443 49.38 14.923 25.743 13.221 20.808 55.73 10.147 11.732 13.221 17.854 20.869 25.425 31.773 39.705 46.053 61.92 13.221 16.274 19.444 24.036 28.598 34.943 41.29 49.225 14.803 25.608 13.101 20.668 55.575 9.568 11.156 12