BSPT (British Standard Pipe Taper) and NPT (National Pipe Taper) are two different standards for tapered threads used in pipe fittings.
What is the BSPT thread?
BSPT thread is tapered, meaning they become narrower along the length of the thread. This taper is what allows BSPT connections to create a seal by wedging the threads together as they are tightened. It has an included angle of 55 degrees. The thread pitch (the distance between successive threads) for BSPT threads can vary depending on the size of the thread and the specific standard being used. Common sizes include 19 threads per inch (TPI) and 14 TPI. It primarily used in the Europe.
What is the NPT thread?
NPT thread is also tapered, which means the threads get narrower along the length of the thread. This taper is essential for creating a tight seal when the threads are tightened together. It has an included angle of 60 degrees. The thread pitch (the distance between successive threads) for NPT threads is standardized, and it varies depending on the size of the thread. Common sizes include 18 threads per inch (TPI) for 1/8″ to 1″ sizes and 14 TPI for larger sizes. It primarily used in North America.
BSPT and NPT threads are not directly interchangeable due to the differences in taper angle and sealing mechanism. Attempting to connect them without proper adaptation may lead to leakage or damage.
When working with pipe fittings and connections, it’s important to ensure that you are using the correct thread standard for your specific application to prevent leaks and ensure a secure fit. Adapters are available to facilitate connections between BSPT and NPT threads when necessary, but it’s essential to use them properly to maintain the integrity of the connection. If you want to learn more, please contact QC Hydraulics.