Threaded Inserts Standards; Information About NPT and Metric Threads

Threaded Inserts Standards; Information About NPT and Metric Threads

Threaded Inserts Standards; Information About NPT and Metric Threads

Are different thread standards confusing you? In this article, we will explain the basic differences between NPT and Metric Threads and provide tips on which one you should choose.

Thread standards; a set of rules and features that ensure screws, nuts, or connecting equipment are securely and firmly connected to each other. These standards specify the measurements and criteria to be followed regarding the size, shape, pitch, and tolerances of the threads.

The two most commonly used thread standards worldwide are the metric and inch systems.

Metric Thread:

As the name suggests, it is used in Europe and many countries using the metric measurement unit.

Measurements are defined in millimeters (mm).

It has a 60° thread angle.

There are two types of metric threads; coarse and fine. Coarse-threaded screws are suitable for general-purpose use, while fine-threaded screws are used in more precise connections.

NPT (National Pipe Thread):

Widely used in the United States and Canada, which use the inch (in) measurement unit.

Measurements are defined in inches.

It has a 60° thread angle.

It has a tapered thread shape, which increases sealing.

NPT threaded screws are used in pipes and connecting parts carrying liquid and/or gas. 

You can examine the differences between NPT and Metric Threads in the table below.

NPT and metric threads are not compatible with each other. Therefore, you need to use an adapter to connect two pipes or connecting parts with different thread types.

Other Thread Standards:

BSP (British Standard Pipe): Used in the United Kingdom and some Commonwealth countries.

JIS (Japanese Industrial Standard): Used in Japan.

UNC (Unified Coarse Thread) and UNF (Unified Fine Thread): Used in the United States.

Which Thread Standard Should I Choose?

The thread standard you choose depends on your usage purpose and needs.

  • If you will use a high-pressure application, NPT threads might be a better choice.
  • If easy installation is important for you, metric threads might be a better choice.
  • If you are undecided, you can get detailed information by sending an email to satis@protas.com.tr.

Always Ready with Our Ex Equipment!

#Protas #WorkSafely