What diffrent between PT, NPT and FPT thread
What diffrent between PT, NPT and FPT thread
(OP)
Hello! I have some problem with the different between pipe thread of PT, NPT, FPT. I used to supply aome air valve with port size from 1/4"NPTF to 1/2" NPTF. Because a customer if require NPTF thread then he /she will states NPTF. But sometimes a US customer only say nedd Pipe taper thread or PT port etc, I will have question on PT, NPT or FPT. Are PT, NPT, FPT same thread?
RE: What diffrent between PT, NPT and FPT thread
NPT: National Pipe Taper Thread A sealant or Teflon tape must be used for a leak-free seal.
FPT: female(internal) National Pipe Taper Threads
MPT: male(external) National Pipe Taper Threads
NPTF: Dry-seal American National Standard Taper Pipe Thread (pressure-tight) No sealant is needed for a seal.
The NPT and NPTF threads are interchangeable with sealants such as teflon tape. None of the other thread standards are interchangeable.
NPS/NPSM: American Standard Straight Pipe Thread Used for mechanical joining -- holding a fitting in place. An O-ring or a metal seal is required.
Two common pipe thread sizes exist, the tapered National Pipe Thread (NPT) and the straight National Standard Free-Fitting Straight Mechanical Pipe Thread (NPSM). The tapered threads are for joining and sealing, the straight threads are only for joining. The Dry-seal thread (NPTF) allows for joining without sealants.
The other thread acronyms that exist are:
NPSI: American National straight intermediate pipe thread
NPSF: Dry-seal American National Standard Straight Pipe Thread
GHT: Garden Hose Thread
NST: Fire Hose Coupling
BSPT: British Standard Pipe Taper threads
BSPP: British Standard Pipe Parallel (straight) threads
Hope this helps.