What Is The Difference Between Npt And Bspt Thread?

Jianzhi is a leading manufacturer specializing in NPT thread fittings and BSPT thread fittings. With advanced production technology and strict quality control, Jianzhi offers high-quality threaded fittings that meet international standards. These fittings are widely used in various industries, including plumbing, gas, and oil pipelines, providing reliable and durable solutions for different piping systems.

Depending on the location, size, and environmental factors of the pressure system, numerous types of seals are used in process industries. The type of seal used also depends on industry preferences and regional variations. Let’s discuss npt vs bspt.

NPT Connections

William Sellers established the American standard for screws, bolts, and nuts in 1864, which later became known as the National Pipe Tapered Thread (NPT). His 60-degree thread angle, which early American clockmakers frequently employed, made the Industrial Revolution possible. Later on, these thread types evolved into the American National Standard.

Whitworth threads, with at least one thread tapered, were selected as self-sealing connection threads for pipes. This gave rise to the British Standard Pipe thread, commonly referred to as the BSP Taper or BSP Parallel thread. These days, the Whitworth thread—which is common around the world—is used to attach low carbon steel pipes.

NPT (National Pipe Thread) seals are the most widely utilized kind of seal in pressure calibration systems. A taper thread on NPT male adapters fits into the female NPT adapter. The reason they seal is because of the “out of roundness principle,” which states that the male pulls the female fitting until the connection is strong enough to withstand pressure. A problem with this design is that excessive tightening or inadequate lubrication can lead to galling and damage to the threads when connecting stainless steel to stainless steel. To seal, thread sealant is needed, but just two turns are needed. Any more than that and the seal can leak around the thread sealant.