3/4

For 3/4, thread standard is BSPT; threads per inch (tpi) is 14; thread pitch (mm) is 1.814; major (outside) diameter (mm) is 26.44; minor diameter (mm) is 24.12, recorded from its source on 2026-08-12.

Values marked our reading are our classification of what the source says — the source does not print them in those words. The quote below is the evidence for each one; judge it yourself.

What the source says

<https://www.machiningdoctor.com/threadinfo-bspt/?tid=4505> BSPT R 3/4 | 3/4" | 14 | 1.814 | 9.5 | 1.0 / 1.8 | 26.44 | 25.28 | 24.12 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4506> BSPT R 1 | 1" | 11 | 2.309 | 10.4 | 1.0 / 2.3 | 33.25 | 31.77 | 30.29 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4507> BSPT R 1 1/4 | 1 1/4" | 11 | 2.309 | 12.7 | 1.0 / 2.3 | 41.91 | 40.43 | 38.95 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4508> BSPT R 1 1/2 | 1 1/2" | 11 | 2.309 | 12.7 | 1.0 / 2.3 | 47.80 | 46.32 | 44.85 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4509> BSPT R 2 | 2" | 11 | 2.309 | 15.9 | 1.0 / 2.3 | 59.61 | 58.14 | 56.66 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4510> BSPT R 2 1/2 | 2 1/2" | 11 | 2.309 | 17.5 | 1.5 / 3.5 | 75.18 | 73.71 | 72.23 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4511> BSPT R 3 | 3" | 11 | 2.309 | 20.6 | 1.5 / 3.5 | 87.88 | 86.41 | 84.93 | 0 | -999.00 | R | <https://www.machiningdoctor.com/threadinfo-bspt/?tid=4512> BSPT R 4 | 4" | 11 | 2.309 | 25.4 | 1.5 / 3.5 | 113.03 | 111.55 |

— machiningdoctor.com, retrieved 2026-08-12

Source

• machiningdoctor.comhttps://www.machiningdoctor.com/charts/bsp/

Last verified against source: 2026-08-12. Due for re-check by 2028-08-11. This page as Markdown · OKF bundle · full dataset as JSON.