Unique Product Features

The male and female threads have a tapered flank and controlled truncation at the crest and root to assure metal to metal crest root contact just as the male-female thread flanks make contact. Upon further tightening, the thread crests flatten out and allow the flanks to make full contact. This full thread profile contact theoretically give the tapered threads self-sealing ability. However, variations in condition of mating threads, fitting and port materials, assembly procedures and operating conditions make self-sealing highly unlikely without the aid of paste, tape, or preapplied thread sealants.

NPT (National Pipe Tapered) is made to specifications outlined in ANSI B1.2. This is the pipe thread used on the pipe end.

In application ISO threads are used similar to NPT threads. However, care should be used that ISO and NPT threads are not mixed. ISO threads have a 55? angle versus 60? for NPT. Thread pitch is usually measured in millimeters but may be expressed in inch. In many sizes the threads-per-inch are different and the root and crest configurations are different from NPT.

International Organization for Standards (ISO 228/1) parallel (PF) ISO Parallel threads are equivalent to DIN ISO 228/1, BSP PL, JIS B0202, R 1/8 and R ¼.

These pipe threads are similar in configuration to 7/1 threads except there is no taper. Therefore do not work by thread interference like the tapered pipe threads of ISO 7/1 or NPT. A gasket or O-Ring is normally used to seal into the parallel female threaded component.