NPT thread is an abbreviation for National Pipe Thread, a U.S. standard for pipe threads that are used for pipe connections, especially where a high degree of sealing is required.NPT threads are classified as conical and cylindrical, and the fit methods include ‘cone/cone’ fit and ‘column/cone’ fit. ‘Column/cone’ fits.

The following table shows the specific description of their dimensions:

Source: GB 12716-2011, ASME B1.20.1

NPT Thread Applications and Considerations

NPT threads are widely used for the connection of fuel pipes, oil pipes, water pipes, gas pipes and other machinery and equipment.
When selecting NPT threads, you need to consider factors such as piping requirements, working pressure, and media in order to select the appropriate thread size.
Regularly check and maintain the threaded connection to ensure the connection quality and sealing.
Summary
As a standard pipe thread, the dimensions and specifications of NPT 1/4 thread strictly follow the relevant U.S. national standards. In pipe connections, the correct selection and use of NPT threads is essential to ensure the sealing and reliability of the connection.