工业标准有:ISO、DIN、IDF、3A、SMS等
 |
SIZE | C | D | L | B | A |
| ¾” | 19 | 50.5 | 95 | 50 | 100 | |
| 1” | 25.4 | 50.5 | 120 | 55 | 115 | |
| 1¼” | 32 | 50.5 | 130 | 58 | 130 | |
| 1½” | 38 | 50.5 | 140 | 60 | 150 | |
| 2” | 51 | 64 | 170 | 80 | 180 | |
| 2½” | 63.5 | 77.5 | 190 | 90 | 200 | |
| 3” | 76.3 | 91 | 210 | 95 | 220 | |
| 3½” | 89 | 106 | 220 | 110 | 260 | |
| 4” | 101.6 | 119 | 240 | 118 | 320 |
