| unit:mm | |||||||
M | D | a | Number of spiral | Pitch | L | B | t | R(PT) |
1/8 PT | 9.728 | 0.45 | 28 | 0.91 | 7 | 5 | 3.5 | 1/8 |
1/4 PT | 13.157 | 0.7 | 19 | 1.34 | 8.9 | 6 | 4.5 | 1/4 |
3/8 PT | 16.662 | 10 | 8 | 5 | 3/8 | |||
1/2 PT | 20.955 | 0.9 | 14 | 1.81 | 12 | 10 | 6 | 1/2 |
3/4 PT | 26.441 | 14 | 14 | 7 | 3/4 | |||
1 PT | 33.429 | 1.1 | 11 | 2.31 | 16.5 | 17 | 9 | 1 |