NPT vs BSP Thread

NPT vs BSP Thread

What is npt thread?

NPT stands for National Pipe Thread. It is also known as the American National Pipe Thread. The NPT thread is usually available in two forms- Tapered and Straight thread series. The NPT thread has many applications due to its rigidity, pressure-tight sealing, etc.

The NPT threads have a taper that allows them to create a seal while torquing because the flanks of the threads compress against each other. The sizes of NPT pipe thread are available in different sizes. The smaller sizes of NPT threads are applicable for compressed air.

Npt vs bsp thread specification

Npt bsp thread sizes

NPT thread full form is national pipe tapered thread, whereas bsp stands for British standard pipe thread

What is bsp thread?

BSP stands for British Standard Pipe. It is the most commonly applicable thread system worldwide in the piping and fitting industry. BSP fine thread uses Whitworth Standard Threads as per ISO 228 standards.

The BSP threads are widely used in various industries to connect and seal pipes and fittings. These BSP metric threads are the plumbing and pipe fitting industry standard. They also apply in power plants, oil and gas, chemical, manufacturing, shipping, etc.

Check number of threads per inch in NPT

Npt thread and bsp thread difference

There are striking differences between NPT and BSP threads; they are:

  • The BSP thread is widely used in most countries, while the NPT thread is commonly used in the United States and Canada.
  • NPT Thread is applicable for rigidity and pressure-tight sealing. BSP Thread is applicable for connecting and sealing pipes and fittings.
  • NPT vs BSP Thread is fundamentally different in their angles. The NPT threads have 60 degrees of angulation, and the BSP threads have 55 degrees of angulation.
  • NPT threads have peaks and valleys, while BSP threads are flat.

NPTF thread is a dryseal tapered pipe thread and creates leakproof seals without the use of a sealant, know moe about NPT tapered

What is npt thread gauge checking method?

The procedure to gauge the Internal NPT pipe threads is to screw the threaded plug firmly into the product without applying too much force. When the gaging notch of the plug is one turn plus or minus from being flush with the end of the product, it is proven to be under permissible tolerance.

The only way to check the NPT thread gauge is to thread the L-1 gauge with the tapered thread until a tight fit is felt. When the gauge stops, the plug gauge notch or flat ring gauge must be within plus or minus one turn from the face of the thread.

BSP male/ female threads are the standard design for most of the world’s tapered threads

Difference between npt vs nptf

There are huge differences between NPT and NPTF; they are:

  • Both are tapered pipe threads. However, the NPT thread is used for general purposes, but the NPTF is applicable in dry seal areas.
  • The NPT thread roots design allows for clearance with mating threads, unlike the NPTF thread angle, which interferes with the mating crests.
  • Checking NPT requires an L1 plug and ring. However, checking NPTF requires L2 and L3 plugs and rings.
  • The allowance between the crest and the root makes room for a sealant in NPT threads. Unlike NPTF thread taper angle, which provides a mechanical seal as there is interference between the crest and the root.
NPT and BSP threads are not interchangeable due to the differences in thread forms.

Difference between bsp vs bspt

There are striking differences between BSP and bspt; they are:

  • The configuration of BSP threads is in parallel, unlike that of BSPT, which has a taper.
  • The BSPT threads, unlike BSP threads, do not have the shoulders to seal a washer.
  • The seal in the BSP male thread is made using a washer. While in the BSPT thread, the male thread is wrapped many times around PTFE jointing tape to create a seal with the female thread.
  • The width of BSP threads is similar all along, unlike that of BSPT thread, which has a taper.