When it comes to different thread types, most people who work in the fluid-power industry will recognize American pipe threads (NPT/NPTF), SAE or
When it comes to hose and tube fittings, there are a number of different types of threads available. The number of fitting end options can make selecting the most appropriate fitting thread type a daunting task. The reliability of the fitting connection depends on selecting what’s optimal for the application. First, we will educate you about six types of common thread types. Second, we will guide you through the thread identification process.
When it comes to different thread types, most people who work in the fluid-power industry will recognize American pipe threads (NPT/NPTF) as well as SAE or Unified threads (UN/UNF). However, threads and connections are divided into six main types:
Let’s learn the difference between each one of them.
Before you start, make sure you have two thread identifying tools on hand:
A pitch gauge is a tool used to measure the distance between the crests of threads. For NPT, UN/UNF, BSPP, and BSPP we measure the number of threads per inch. If you have the metric threads, the pitch gauge identifies the distance between each individual crest in millimeters.
A caliper is used to measure the diameter of a thread. For male threads, it measures the outside diameter, for a female thread – inside diameter, respectively. For advanced users, a digital caliper is available from multiple retailers. It saves your time and simplifies the process.