NPSpipe60° flankASME B1.20.1

1/2-14 NPS Thread Dimensions

1/2-14 NPS is a pipe National Pipe Straight thread. There are 14 threads per inch on a 0.8402 in major diameter, giving a metric-equivalent pitch of 1.814 mm. The size label is a nominal bore rather than a diameter.

Major Ø0.8402 in
Threads per inch14
Pitch (metric)1.814 mm
Pitch Ø0.7937 in
Tap drill0.7685 in

Thread profile

millimetres unless stated
Thread profile — 1/2-14 NPSd 21.34d2 20.16d3 18.71mm60°P 1.814h3 1.451tap ⌀19.52
1/2-14 NPS — basic profile60° flank angle · Not to scale

Basic information

Designation
1/2-14 NPS
Thread system
National Pipe Straight
Series
pipe
Standard
ASME B1.20.1
Basic profile
Unified profile, 0.8P thread height
Flank angle
60°

Dimensions

Major diameter
0.8402 in / 21.34 mm
Pitch (metric equivalent)
1.814 mm
Threads per inch
14
Pitch diameter
0.7937 in / 20.16 mm
Minor diameter (external)
0.7366 in / 18.71 mm
Minor diameter (internal)
0.7626 in / 19.37 mm
Thread depth
0.0571 in / 1.451 mm
Recommended tap drill
Ø 0.7685 in / 19.52 mm

How these values are derived

tabulated standard values

This is a pipe thread, so the published dimensions are tabulated values from ASME B1.20.1 rather than figures derived from a formula: a pipe size is a nominal bore, and the relationship between that bore and the thread diameter is historical, not geometric. Diameters are quoted at the gauge plane; the thread itself is tapered, so the actual size changes along its length.

Compatible parts0 specification pages

No specification in this database uses 1/2-14 NPS. That is expected: the catalogue covers machine screws, bolts, nuts and washers, and pipe threads belong to fittings, which are a separate family of parts. The dimensions above are still the standard ones for the thread itself.

Related

Neighbouring sizes in National Pipe Straight.

1/8-27 NPS1/4-18 NPS3/8-18 NPS3/4-14 NPS1-11.5 NPS1-1/4-11.5 NPS1-1/2-11.5 NPS