Steel Tube Sizes Pdf. 232 2. The taper rate for all NPT threads is 1⁄16 (3&frasl
232 2. The taper rate for all NPT threads is 1⁄16 (3⁄4 inch per foot) measured by the change of diameter (of the pipe thread) over distance. 300 N/A N/A N/A 0. 625 9. 3 mm – 26. 400 2. 232 3. 375 0. 232 4. 982 3.