BSP thread, nominal size 1-1/8 — dimensions
For BSP thread, nominal size 1-1/8, threads per inch (tpi) is 11; thread pitch (mm) is 2.309; major (outside) diameter (mm) is 37.897; minor diameter (mm) is 34.939; thread angle (degrees) is 55; governing standard is ISO 228-1, recorded from its source on 2026-08-12.
- Thread standard
- BSP our reading
- Nominal size
- 1-1/8
- Threads per inch (TPI)
- 11
- Thread pitch (mm)
- 2.309
- Major (outside) diameter (mm)
- 37.897 verified
- Minor diameter (mm)
- 34.939
- Thread angle (degrees)
- 55 our reading
- Governing standard
- ISO 228-1 our reading
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
1.4920 | 37.897
— en.wikipedia.org, retrieved 2026-08-12
Source
- en.wikipedia.orghttps://en.wikipedia.org/wiki/British_Standard_Pipe