What Is The Size of The Npt Fitting?

by | Sep 26, 2024 | News

China NPT pipe fittings are a crucial component in many piping systems, known for their exceptional durability and flexibility. Manufactured by JianZhi Fittings, these fittings are made from malleable iron, which has been heat-treated to enhance its ductility. This process ensures that China NPT pipe fittings are designed to withstand high pressures and mechanical stresses, making them ideal for both residential and industrial applications. The unique properties of malleable iron allow it to be shaped into various configurations, offering versatility in complex piping layouts. This adaptability ensures that China NPT pipe fittings can be used in a wide range of plumbing and mechanical systems, providing reliable connections that are resistant to cracking or breaking under stress.

npt pipe fitting

Leading manufacturer Jianzhi specializes in both BSPT and NPT thread fittings. Jianzhi provides premium threaded fittings that satisfy worldwide standards thanks to its sophisticated production technology and stringent quality control measures. These fittings offer dependable and long-lasting solutions for numerous piping systems, and are widely utilized in a variety of industries, including plumbing, gas, and oil pipelines.

Process industries use a wide variety of seals, depending on the pressure system’s location, size, and environmental conditions. Regional variances and industry preferences also influence the type of seal that is employed.

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.

In pressure calibration systems, NPT (National Pipe Thread) seals are the most commonly used type of seal. NPT male adapters have a taper thread that slides into the female adapter. The “out of roundness principle,” which claims that the male tugs the female fitting until the connection is strong enough to withstand pressure, is the reason they seal. One issue with this design is that when joining stainless steel to stainless steel, excessive tightness or insufficient lubrication can cause galling and damage to the threads. Thread sealant is required for sealing, however only two spins are required. If you use more, the thread sealant may seep through the seal.

How to Determine NPT Fitting Sizes

NPT fitting sizes can often cause confusion, as they don’t match the actual physical dimensions of the fitting. Instead, NPT sizes correspond to the nominal pipe size (NPS), which relates to the inside diameter of the pipe that the fitting connects to, not the outer dimensions of the fitting itself. For example, a 1/2” NPT fitting does not have an outer diameter of 1/2”, but rather, it fits into a pipe with a nominal diameter of 1/2”.

The most common NPT sizes range from 1/8” to 2” for smaller-scale applications, although larger sizes are available for industrial use.

Key Points for Measuring NPT Sizes:

Npt pipe fitting sizes: The NPT size is based on the pipe’s inside diameter, not the fitting’s external dimensions.

Tapered Threads: The threads are tapered to provide a tight seal, and measurements should take this into account.

Thread Pitch: The number of threads per inch must be measured to ensure the proper fit. NPT thread pitch varies based on size.

Outside Diameter (OD): The actual outside diameter of the fitting is larger than the NPT size, which can be confusing for those unfamiliar with these measurements.

Jianzhi is NPT pipe fittings suppiler, offering npt pipe fittings catalog, for example, 

NPT female thread

NPT male thread

BSPT female thread

BSPT male thread.

Leading the industry, Jianzhi Manufacturing boasts a top-notch technical research and development staff in addition to cutting-edge production tools and testing techniques. The company consistently develops new goods that satisfy market demand and stays true to its customer-centered, market-oriented philosophy.