BSPP (G) — British parallel pipe

1-1/2-11 BSPP

1-1/2-11 BSPP pipe thread: 11 TPI, major Ø 47.803 mm.

Tap-drill calculator Identify a thread

Tap drill

—

47.803 mm major Ø

Profile

Thread form & key diameters

Dimensions

Designation	1-1/2-11 BSPP
Major (outside) diameter	47.803 mm · 1.882"
Pitch	2.309 mm · 11 TPI
Pitch diameter	46.303 mm · 1.823"
Minor diameter (external)	44.97 mm · 1.7705"
Minor diameter (internal)	45.303 mm · 1.7836"
Recommended tap drill	—

What tap drill do I need for 1-1/2-11 BSPP?

1-1/2-11 BSPP is a BSPP pipe thread running at 11 threads per inch on a 47.803 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.

Same diameter

Other 1-1/2" BSPP threads

1-1/2-11 BSPTTap 44.5 mmØ 47.803 mm · pitch 2.309 mm

Nearby sizes

More bspp (g) — british parallel pipe threads

1-1/4-11 BSPPTap —Ø 41.91 mm · pitch 2.309 mm 2-11 BSPPTap —Ø 59.614 mm · pitch 2.309 mm 1-11 BSPPTap —Ø 33.249 mm · pitch 2.309 mm 3/4-14 BSPPTap —Ø 26.441 mm · pitch 1.814 mm 1/2-14 BSPPTap —Ø 20.955 mm · pitch 1.814 mm 3/8-19 BSPPTap —Ø 16.662 mm · pitch 1.337 mm 1/4-19 BSPPTap —Ø 13.157 mm · pitch 1.337 mm 1/8-28 BSPPTap —Ø 9.728 mm · pitch 0.907 mm