NPTF
NPTF is a tapered dryseal thread used to form a seal through controlled thread interference. It is widely used in North American hydraulic and pneumatic equipment.
Selection Guidance
Because sealing is achieved differently from BSPP, ORFS or JIC, NPTF parts should not be mixed with those standards without the correct conversion adaptor.
Sealant policy depends on the application, mating quality and operating conditions, so assembly practice still matters.