VHP National Pipe Tapered Fuel (NPTF)

This is a dryseal thread, the National Pipe Taper Fuel (NPTF) thread. It is used for both male and female ends. This connection is still widely used in fluid power systems, even though it is not recommended by the National Fluid Power Association (NFPA) for hydraulic applications. The NPTF male will mate with NPTF, NPSF, or NPSM females. The NPTF male has tapered threads and a 30° inverted seat. The NPTF female has tapered threads and no seat. The seal is achieved through thread deformation. The NPSM female has straight threads and a 30° inverted seat. The seal is achieved on the 30° seat. The NPTF connector is similar to, but not interchangeable with, the BSPT connector. In most sizes, the thread pitch is different. The thread angle is 60° instead of the 55° angle used for BSPT threads.