3-8NPSH vs 3-8 NPT: specs compared
Updated 05 September 2026.
88.9 mm
3-8 NPT wins on major diameter
On major diameter, 3-8 NPT leads: 88.9 mm versus 88.14 mm.
| Spec | 3-8NPSH | 3-8 NPT |
|---|---|---|
| Designation | 3-8NPSH | 3-8 NPT |
| Major diameter | 88.14 mm | 88.9 mm |
| Threads per inch / pitch | 8 | 8 |
| Thread form | straight (parallel), 60 degree | tapered, 60 degree |
| Seals on | gasket in the coupling | on the thread flanks with PTFE tape |
Questions and answers
Which has the higher major diameter, 3-8NPSH or 3-8 NPT?
On major diameter, 3-8 NPT leads: 88.9 mm versus 88.14 mm.
How do 3-8NPSH and 3-8 NPT compare?
On major diameter, 3-8 NPT leads: 88.9 mm versus 88.14 mm.