Take you to understand various thread standards
Take you to understand various thread standards
NPT is a general purpose American standard taper pipe thread with a 60 ° profile angle.
PT is an inch taper thread with a profile angle of 55 ° and is most commonly used in sealing. British pipe thread is fine thread, because the depth of coarse thread is large, it will seriously reduce the strength of the pipe with external diameter cut.
PF is parallel thread for pipe.
G is a 55 degree non threaded sealing pipe thread, belonging to the Wyeth thread family. The mark g represents cylindrical thread, G is the general designation of pipe thread (Guan). The division of 55 and 60 degrees is functional
ZG is commonly known as pipe cone, that is, the thread is processed from a circular cone surface. The general water pipe joint is like this, and the old national standard is marked as RC.
Metric thread is represented by pitch, while American British thread is represented by thread number per inch, which is the biggest difference between them. Metric thread is 60 degree isometric thread, British thread is isosceles 55 degree profile, and American thread is 60 degree. Metric units are used for metric threads, and English units are used for American and British screw threads.
Pipe thread is mainly used for pipe connection, and its internal and external threads fit closely, including straight pipe and taper pipe. The nominal diameter refers to the diameter of the pipe connected. It is obvious that the major diameter of the thread is larger than the nominal diameter.
