BSPT (R) - British tapered pipe

3/4-14 BSPT

3/4-14 BSPT pipe thread: 14 TPI, major Ø 26.441 mm.

Tap drill
23.75 mm
26.441 mm major Ø

Profile

Thread form & key diameters

Major Ø 26.441 mmP 1.814 mm55°Root Ø 24.215 mm · Pitch Ø 25.263 mm3/4-14 BSPT14 TPI · 55° form

Dimensions

Dimensions, drill sizes and wrench sizes for 3/4-14 BSPT.
Designation3/4-14 BSPT
Major (outside) diameter26.441 mm · 1.041"
Pitch1.814 mm · 14 TPI
Pitch diameter25.263 mm · 0.9946"
Minor diameter (external)24.215 mm · 0.9534"
Minor diameter (internal)24.477 mm · 0.9637"
Recommended tap drill23.75 mm

Tightening torque estimate

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.

Put 3/4-14 BSPT on a job sheet

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.

Open bolt schedule

What tap drill do I need for 3/4-14 BSPT?

3/4-14 BSPT is a BSPT pipe thread running at 14 threads per inch on a 26.441 mm major diameter. BSPT (R) is a 55° Whitworth tapered thread that seals on the flanks.

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.

Frequently asked questions

What drill size do I need to tap 3/4-14 BSPT?

Drill 23.75 mm before tapping 3/4-14 BSPT. BSPT (R) is a 55° Whitworth tapered thread that seals on the flanks.

Is 3/4-14 BSPT a tapered or parallel thread?

3/4-14 BSPT is tapered. BSPT (R) is a 55° Whitworth tapered thread that seals as the flanks wedge together, normally with thread sealant or PTFE tape.

How many threads per inch does 3/4-14 BSPT have?

3/4-14 BSPT runs at 14 threads per inch, a pitch of 1.814 mm, on a major diameter of 26.441 mm.

Is there a torque spec for 3/4-14 BSPT?

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

Other 3/4" BSPT threads

The pipe this thread runs on

NPS 3/4 pipe

NPS 3/4 pipe is 1.05 in across the outside whatever the schedule; at standard wall (std) the wall is 0.113 in and the bore 0.824 in.

Full dimensions for the standard wall · every schedule in the chart

Nearby sizes

More bspt (r) - british tapered pipe threads