1pc NPT ball valve

1pc NPT ball valve

A 1pc NPT ball valve can also be callled reduced bore NPT ball valve, it meets the NPT (National Pipe Thread) standard,which is a U.S. standard for tapered threads used on threaded pipes and fittings. The taper rate for all NPT threads is ¹?₁₆ (? inch per foot) measured by the change of diameter (of the pipe thread) over distance. The taper divided by a center line yields an angle 1° 47' 24" or 1.7899° as measured from the center axis. Commonly-used sizes are ?, ?, ?, ?, ?, 1, 1?, 1?, and 2 inch, appearing on pipes and fittings by most U.S. suppliers. Smaller sizes than those listed are occasionally used for compressed air. Larger sizes are used less frequently because other methods of joining are more practical at 3 inches and above in most applications. It is defined by ANSI/ASME standard B1.20.1.

Nominal Pipe Size is loosely related to the inside diameter of Schedule 40 pipe. Because of the pipe wall thickness, the actual diameter of the threads is larger than the NPS, considerably so for small NPS. Other schedules of pipe have different wall thickness but the OD (outer diameter) and thread profile remain the same, so the inside diameter of the pipe is therefore different from the nominal diameter.

There is also a semi-compatible variant called National Pipe Taper Fuel (NPTF) also called Dryseal American National Standard Taper Pipe Thread, defined by ANSI B1.20.3, designed to provide a more leak-free seal without the use of teflon tape or other sealant compound. NPTF threads are the same basic shape but with crest and root heights adjusted for an interference fit, eliminating the spiral leakage path.