Pipe Taps
Pipe Taps are high-speed cutting tools that are used to cut internal threads in pipes or pipe fittings that will provide an effective seal when mated with the appropriate component.
When mated, pipe threads form a pressure-tight seal that allows the flow of liquids, gases, steam, and hydraulic fluid, without leaking.
Haas offers various types of pipe thread taps that are designed to form a seal with or without thread sealants. NPT/NPS and BSPT/BSPP threads are not compatible due to differing thread pitches. Moreover, NPT/NPS threads follow the Sellers Standard thread form, which has flattened peaks and valleys, as well as a 60° thread angle. BSPT/BSPP threads follow the Whitworth thread form, which has a 55° thread angle, and rounded peaks and valleys.
Pipe Thread Types and Sealing Methods
Overview of common pipe thread standards (NPT, NPTF, NPS, NPSF, G-Series), highlighting their sealing mechanisms, thread shapes, and typical applications in pressure and fuel systems.
- NPT (National Pipe Taper): commonly found on the ends of pipes, nipples, and fittings. Tapered for sealing, often without any sealant. The taper allows them to form a seal when torqued, as the flanks of the threads compress against each other.
- NPTF (National Pipe Taper-Fuel): also known as Dryseal, for pressure-tight connections, especially in fuel applications. Provides a leak-free seal without the use of sealant.
- NPS (National Pipe Straight): For rigidity. Needs a gasket, sealant, or O-ring to create the seal. However, sometimes the straight thread enclosed by a tapered thread can form a low-pressure seal.
- NPSF (National Pipe Straight-Fuel): also known as Dryseal, these are internal-only straight threads that provide a leak-free seal without the use of sealant.
- G-Series, also known as BSPP/BSPF/BSPM (British Standard Pipe Parallel): Per ISO-228, they are for rigidity. Needs a gasket, sealant, or O-ring to create the seal. However, sometimes the straight thread enclosed by a tapered thread can form a low-pressure seal. 55° thread angle with rounded peaks and valleys.
BSPT/BSPP
- Follow the Whitworth thread form, which has rounded peaks and valleys
- 55° thread angle
NPT/NPS:
- Threads follow the Sellers Standard thread form, which has flattened peaks and valleys
- 60° thread angle