R3 vs 3-8NPSH: specs compared
Updated 05 September 2026.
88.14 mm
3-8NPSH wins on major diameter
On major diameter, 3-8NPSH leads: 88.14 mm versus 87.884 mm.
| Spec | R3 | 3-8NPSH |
|---|---|---|
| Designation | R3 | 3-8NPSH |
| Major diameter | 87.884 mm | 88.14 mm |
| Threads per inch / pitch | 11 | 8 |
| Thread form | tapered, 55 degree | straight (parallel), 60 degree |
| Seals on | on the thread flanks with PTFE tape or paste | gasket in the coupling |
Questions and answers
Which has the higher major diameter, R3 or 3-8NPSH?
On major diameter, 3-8NPSH leads: 88.14 mm versus 87.884 mm.
How do R3 and 3-8NPSH compare?
On major diameter, 3-8NPSH leads: 88.14 mm versus 87.884 mm.