Basic Dimensions, American National Standard Taper Pipe Threads, NPT Pitch Diameter Formulas and Calculator NPT American National Standard Taper Pipe Threads Notes: Reference ANSI/ASME B1.20.1-1983 (R1992) Angle between sides of thread is 60 degrees. Thread taper, is 3⁄4 inch per foot. ...
TL;DR (Too Long; Didn't Read) The tangent of an angle is the ratio of the opposite side of the triangle over the adjacent side. This is the same ratio as a taper. If your calculator does not have the arctangent function, use an online angle calculator. References Ace Designers: Using...