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NPTF dryseal pipe

NPTF dryseal threads include specific crest and root limits as well as the tapered pipe diameters and engagement lengths.

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Example designation

1/16-27 NPTF

1/16
Nominal pipe size.
27
Threads per inch.
NPTF
Dryseal pipe thread family.
Calculate this example

Check the crests and roots

Review the crest-flat, root-flat, and truncation ranges with the diameter results. Matching the nominal size and TPI of an NPT thread does not establish the NPTF profile.

External and internal lengths

Alongside L1 hand engagement, L2 effective length, L3 wrench makeup, and L4 overall external length, the results include the applicable overall internal length.

Keep the wire datum

The two-wire result belongs at the gauge datum. A measurement taken farther along the taper represents a different diameter, even with the same selected wire.