NPT, PT, and G are all tube threads.
1. The N P T thread is short for National (American) Pipe Thread, the American standard 60-degree cone tube thread, for use in North America. National standards are available at GB / T12716-1991.
2.PT thread is the abbreviation of Pipe Thread, is a 55 degree sealed cone tube thread, is a Wyeth thread family, mostly used in Europe and the Commonwealth countries, commonly used in water and gas pipe industry, taper regulation is 1:16. National standard available GB / T7306-2000
3.G thread is a 55 degree non-threaded sealed pipe thread, belongs to a Wyeth thread family. The ker G represents the cylindrical thread. National standards are available at GB / T7307-2001
