圆锥管螺纹尺寸
| 螺纹代号 | 基本尺寸(英 寸) | 大径(mm) | d=D 螺距(mm) | 每英寸牙数 | 中径(mm) | d2=D2 小径(mm) | 外螺纹d3 牙型高度 | r 底孔尺寸 | r 底孔尺寸 |
| R 1/16 | 1/16" | 7.723 | 0.9 | 28 | 7.142 | 6.561 | 0.6 | 0.125 | 6.4 |
| R 1/8 | 1/8" | 9.728 | 0.9 | 28 | 9.147 | 8.566 | 0.6 | 0.125 | 8.4 |
| R 1/4 | 1/4" | 13.157 | 1.3 | 19 | 12.301 | 11.445 | 0.9 | 0.184 | 14.75 |
| R 3/8 | 3/8" | 16.662 | 1.3 | 19 | 15.806 | 14.95 | 0.9 | 0.184 | 14.75 |
| R 1/2 | 1/2" | 20.955 | 1.8 | 14 | 19.793 | 18.631 | 1.2 | 0.249 | 18.25 |
| R 3/4 | 3/4" | 26.441 | 1.8 | 14 | 25.279 | 24.117 | 1.2 | 0.249 | 23.75 |
| R 1 | 1" | 33.249 | 2.3 | 11 | 31.77 | 30.291 | 1.5 | 0.317 | 30 |
| R 1 1/4 | 1,1/4" | 41.91 | 2 | 11 | 40.431 | 38.952 | 1.5 | 0.317 | 38.5 |
| R 1 1/2 | 1,1/2" | 47.803 | 2.3 | 11 | 46.324 | 44.845 | 1.5 | 0.317 | 44.5 |
| R 2 | 2" | 59.614 | 2.3 | 11 | 58.135 | 56.656 | 1.5 | 0.317 | 56 |
| R 2 1/2 | 2,1/2" | 75.184 | 2.3 | 11 | 73.705 | 72.226 | 1.5 | 0.317 | 71 |
| R 3 | 3" | 87.884 | 2.3 | 11 | 86.405 | 84.926 | 1.5 | 0.317 | 85.5 |
| R 4 | 4" | 113.03 | 2.3 | 11 | 111.551 | 110.072 | 1.5 | 0.317 | 110.5 |
| R 5 | 5" | 138.43 | 2.3 | 11 | 136.951 | 135.472 | 1.5 | 0.317 | 136 |
| R 6 | 6" | 163.83 | 2.3 | 11 | 162.351 | 160.872 | 1.5 | 0.317 | 161.5 |
Rc表示螺纹特征代号，1/16为尺寸代号——尺寸代号与带有外螺纹管子的孔径相近，单位为英寸。RC表示右旋,手册上是这样说的：大径d=D，中径d2=D2，小径d1=D1,P为螺距，d2=D2=d-0.640327P；d1=D1=d-1.280654P。