R1-1/2 thread: 47.8 mm × 11 TPI
Threads › R1-1/2
R1-1/2 is a BSPT taper (R / Rc) thread: 47.8 mm major diameter, 11 TPI (2.309 mm pitch), 55° form. Tap drill 44.5 mm. Taper thread: the Ø changes along the length, measure near the start.
| Standard | BSPT taper (R / Rc) |
|---|---|
| Major diameter | 47.803 mm (1.882″) |
| Pitch | 11 TPI (2.309 mm) |
| Thread angle | 55° |
| Tap drill | 44.5 mm |
Open R1-1/2 in BenchsmithAdd to order list
Measure it
Bolt: Measure across the crests of the bolt with the caliper jaws. Worn bolts read 0.1 to 0.3 under.
Nut or tapped hole: Measure across the tops of the threads inside the nut or hole with the inside jaws. That is the minor Ø. Worn or oversize holes read a little over.
Close in size, won't mate
- G1-1/2Ø47.8 mm, 11 TPI
- M48Ø48 mm, 5 mm pitch
- M48×3Ø48 mm, 3 mm pitch
- M48×2Ø48 mm, 2 mm pitch
- 1-1/2-11.5 NPTØ48.26 mm, 11.5 TPI
One size up or down
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.