BSPP (G) - British parallel pipe
1/4-19 BSPP pipe thread: 19 TPI, major Ø 13.157 mm.
Profile
| Designation | 1/4-19 BSPP |
|---|---|
| Major (outside) diameter | 13.157 mm · 0.518" |
| Pitch | 1.337 mm · 19 TPI |
| Pitch diameter | 12.289 mm · 0.4838" |
| Minor diameter (external) | 11.517 mm · 0.4534" |
| Minor diameter (internal) | 11.71 mm · 0.461" |
| Recommended tap drill | - |
Pipe threads are made up to a seal against the mating flanks, not tightened to a bolt preload, so no proof load or tightening-torque figure applies.
The bolt schedule collects the fasteners for one job onto a single sheet - tap drill, wrench size, grade and tightening torque on every line, taken straight from pages like this one. Free schedules hold 3 lines and are saved in this browser only.
1/4-19 BSPP is a BSPP pipe thread running at 19 threads per inch on a 13.157 mm major diameter. BSPP (G) is a parallel thread sealed by a bonded washer or gasket, not by thread interference - so it has no tapered tap-drill sizing.
All values are generated from the standard thread formulas (ISO 68-1 / ASME B1.1) and published standard tables - not hand-entered. See the full reference.
Drill - before tapping 1/4-19 BSPP. BSPP (G) is a parallel thread sealed by a bonded washer or gasket, not by thread interference - so it has no tapered tap-drill sizing.
1/4-19 BSPP is parallel. BSPP (G) threads do not seal on the thread itself; the joint seals on a bonded washer, gasket or O-ring at the face.
1/4-19 BSPP runs at 19 threads per inch, a pitch of 1.337 mm, on a major diameter of 13.157 mm.
No. Pipe threads are made up to a seal against the mating flanks, not tightened to a bolt preload, so no proof load or tightening-torque figure applies.
Same diameter
The pipe this thread runs on
NPS 1/4 pipe is 0.54 in across the outside whatever the schedule; at standard wall (std) the wall is 0.088 in and the bore 0.364 in.
Full dimensions for the standard wall · every schedule in the chart
Nearby sizes