British Standard Pipe
A family of standard screw thread types that has been adopted internationally for interconnecting and sealing pipe ends.
| Nominal Size(inches) | T P I | Pitch(inches) | Major Diameter(inches) | Minor Diameter(inches) | Tapping Drill Size |
| 1/16 | 28 | 0.0357 | 0.304 | 0.2583 | 6.6 mm (Letter drill G) |
| 1/8 | 28 | 0.0357 | 0.383 | 0.3372 | 8.73mm (11/32 inch) |
| 1/4 | 19 | 0.0526 | 0.518 | 0.4546 | 11.8mm (0.4646 inch) |
| 3/8 | 19 | 0.0526 | 0.656 | 0.5886 | 15.25mm (0.6004 inch) |
| 1/2 | 14 | 0.0714 | 0.825 | 0.7336 | 19.05mm (3/4 inch) |
| 5/8 | 14 | 0.0714 | 0.902 | 0.8106 | 21mm (0.8268 inch) |
| 3/4 | 14 | 0.0714 | 1.041 | 0.9496 | 24.5mm (0.9646 inch) |
| 7/8 | 14 | 0.0714 | 1.189 | 1.0976 | 28.25mm (1.1122 inch) |
| 1 inch | 11 | 0.0909 | 1.309 | 1.1926 | 30.75mm (1.2106 inch) |
Subjects: Mechanical Engineering